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EXB-8500 User`s Manual

1. SCSI ID SWITCHES U2 LOGIC LEVEL 1 ON OGIC LEVEL O OFF REMOTE SCSI TERMINATOR MONITOR CONNECTOR P3 R PACKS RP1 RP2 PORT P1 PIN 1 i jr Tg J ages IH B E ML LAM 5000000000000000000000000009 SCSI CONNECTOR P4 PIN 1 GROUND TAB oO GROUNDING HOLE pep J 1 In PIN POWER C NNECTOR P1 Figure 2 1 Connectors and Controls on the Back Panel of the EXB 8500 2 4 510201 2 Installing the EXB 8500 2 Change the settings to the correct address for your configuration Figure 2 2 shows the settings for addresses 0 through 7 Figure 2 2 DIP Switch Settings for the EXB 8500 s SCSI ID Setting the SCSI ID with a Remote Switch The EXB 8500 includes a remote connector labeled P3 to enable you to set the SCSI ID remotely To set the SCSI ID with a remote switch not provided with the EXB 8500 follow these steps 1 Locate the DIP switches labeled U2 on the back of the EXB 8500 as shown in Figure 2 1 2 Setall three DIP switches to off address 3 Locate the remote connector labeled P3 on the back of the EXB 8500 as shown in Figure 2 1 December 1991 2 5 2 Installing the EXB 8500 4 Connect a remote switch to the connector Ensure that the remote switch is no more than 12 inches from the remote connec
2. Bit 7 6 5 4 3 2 1 0 Byte 00 0 0 0 1 0 0 1 1 01 Logical Unit Number Reserved Immed Fixed 02 MSB 03 Verification Length 04 LSB 05 Vendor Unique Reserved 0 0 The VERIFY command enables the EXB 8500 to verify one or more logical blocks of data on the tape beginning with the next logical block When the VERIFY command is completed the tape is positioned on the EOT side of the last block of data verified 27 1 Field Definitions Byte 01 Bit 2 Immed The immediate bit determines when command status is returned to the initiator as follows 0 Status is returned to the initiator when the verify operation is complete 1 Status is returned to the initiator when the VERIFY command is initiated by the EXB 8500 Byte 01 Bit 1 BytCmp The EXB 8500 does not support byte comparison operations The valid value for the BytCmp bit is 0 December 1991 27 1 27 VERIFY 13h 27 2 Byte 01 Bit 0 Fixed The Fixed bit defines the type of verify operation to be performed as follows 0 A single logical block is verified and the length of this block is specified in the Verification Length field 1 One or more fixed length logical blocks are verified and the number of blocks is specified in the Verification Length field The length of each block is either the power on default block length or the length specified with the curren
3. Bit 7 6 5 4 3 2 1 0 Byte 00 0 0 0 1 0 0 0 1 01 Logical Unit Number Reserved Code 02 MSB 03 Count 04 LSB 05 ADE VU Reserved 0 0 The SPACE command enables the EXB 8500 to perform forward or backward searches The EXB 8500 can space over both fixed and variable blocks it determines the type of spacing to use according to the type of block found on the tape Notes December 1991 If the disconnect option is enabled the EXB 8500 can disconnect from the initiator while the SPACE command is executing If a SPACE command in the reverse direction is received after a WRITE 0Ah or WRITE FILEMARKS 10h command any buffered data or filemarks are written to tape before the space operation is performed Completing the write operation includes emptying the buffer to tape and writing the EOD mark EXB 8500 format tapes only This can take up to 12 seconds If an error occurs when the data in the buffer is being written the EXB 8500 returns Check Condition status and the space operation is not performed The initiator should issue a REQUEST SENSE 03h command to determine the cause of the error If the EXB 8500 has the EEPROM image for directory support and the EXB 8500 detects an EOD mark before the first filemark on tape it spaces over the EOD mark at high speed and up to 20 MBytes of erase area until it finds the filemark it is seeking For more information a
4. Appendix D Sense Key Information Sense Key Bh Aborted Command ASC ASCQ Related Byte 12 Byte 13 05h 10h 00h 00h No additional sense information 3Bh 4Eh E7h EBh 43h 00h Message error EOh E5h 47h 00h The command was aborted because of a SCSI bus parity error E6h Sense Key Dh Volume Overflow ASC ASCQ Related Byte 12 Byte 13 Explanation FSC 00h 02h EOT encountered AFh B6h December 1991 D 7 Appendix D Sense Key Information Notes D 8 510201 Appendix E Fault Symptom Codes This appendix lists the Fault Symptom Codes that may be returned by the REQUEST SENSE 03h command The Fault Symptom Code is returned as byte 28 in the Extended Sense Bytes It is an EXABYTE unique byte that specifies the reason for the most recent Check Condition status Note You can also use the Fault Symptom Code field to determine the location of errors in the bytes sent with the MODE SELECT 15h command descriptor block For more information about this use of the Fault Symptom Code refer to Section 12 11 For ease of reference the Fault Symptom Codes FSC are listed in hexadecimal order The information provided for each code includes the sense key SK associated with the code an error recovery procedure ERP code and a brief description of the problem or event Note For more information about the su
5. 4 4 3 Shipping Cartons s 532252293 9 ERR x o kes RS oe deed bas 4 3 Packing the EXB 8300 Roa Ug eR OUR RO eo 4 4 Environmental Requirements for Shipping EXB 8500 4 5 5 Loading New Microcode from 5 1 5 1 Using a Microcode Update Tape 2 2 5999 48 94 2244 Ses 5 1 Steps During Microcode Update 5 1 Time Required to Load Code from Tape sso x ok 2S 5 3 5 2 Creating Microcode Update Tape 25k y ares 5 4 Steps for Making a Microcode Update Tape 5 4 Time Required to Make a Microcode Update Tape 5 6 Part 2 SCSI Commands for the EXB 8500 6 1 6 SCSI Physical Path Communications 6 3 6 1 Message SySieMi 6 ci ca iom so 9 dose 4 39 9 b cw Shu eRe ede 6 4 Message Seguen PPP reaal ge Saad katad 6 10 6 2 SCSI Bus Error Recovery Initiators Supporting Command Complete Message OHY a MM 6 11 6 3 Message Processing and SCSI Bus Error Recovery Initiators Supporting Additional Messages 22d 99v 44 88 RO a ws 6 12 EXB 8500 Response to the Attention Signal 6 12 Message Processing after the Selection Phase 6 13 Message Processing in the Message Out Phase 6 15 Processing during the Command Out Phase 6 17 Message Processing in the Mess
6. December 1991 Bytes 03 through 06 Information The Information bytes contain a value that represents the number of unprocessed blocks or bytes of data resulting from a Check Condition status for the LOCATE READ SPACE VERIFY WRITE or WRITE FILEMARKS commands The value in the Information bytes is valid only when the Valid bit byte 00 bit 7 is set to 1 When the Valid bit is set to 0 any data in these bytes is invalid Byte 07 Additional Sense Length This byte indicates the Additional Sense Length provided by the EXB 8500 excluding this byte The value is 21 15h bytes Bytes 08 through 10 Reserved These bytes are reserved 21 5 21 REQUEST SENSE 03h Byte 11 Underrun Overrun Counter The Underrun Overrun Counter is a dual function counter for logging write underruns and read overruns This counter is used to determine the number of times the initiator failed to maintain the EXB 8500 in streaming mode It will increment any time the EXB 8500 repositions the tape after encountering an empty data buffer during a write operation or a full data buffer during a read operation The counter is reset to 0 after any of the following m A REQUEST SENSE command is issued with the CLRCNT bit byte 05 bit 7 set to 1 Note that in order for the reset to be performed 29 1Dh bytes of sense data must be read by the REQUEST SENSE command m The tape is loaded or rewound m The mode changes from write t
7. B 3 Accessing Data on a Directory Support B 8 Xiv 510201 Appendix C Data Cartridge Capacities C 1 Autosizing of Data CartedBes ua s o secs 17496099 49 ox UN RUE SEO C 1 Shorter Tape sizes dudes s qwe Ch E wed ene a C 1 Longer Tape Sizes 9 254466456 644 858 Roh m own C 2 Track and Physical Block Counts zs RR RERO EORR C 4 Physical Beginning of Tape 4 Logical Beginning of 226 eee eee woo m o C 4 Logical End of Tape LEOT i 5s Rol o ko RR x C 5 Physical Bnd ok Tape BOT ou mee C 5 EXATAPE Capacities erd aca QURE s doa Rech x deu EU ALL C 8 Appendix D Sense Key Information D 1 sense Key UNO Sense uuo c Ele Se 3309 9x oe x 96 Kodex Oe wo D 2 Sense Key 2h Not Ready c ES Re Y 9 ow D 2 Sense Key 3h Medium Error uas Xx OX EUR RR D 3 Sense Key 4h Hardware Error D 4 Sense Key 5h illegal Request og ERA Ro D 5 Sense Key 6h Unit Attention amp awe oe Och do D 6 Sense Key 7b Data Protect uv oa a ORG eS D 6 Sense Key 8h Blank Check quu v 24 8d 9 30 eae Sale ox x 80
8. Status Byte Explanations The following sections explain the Status Byte Codes supported by the EXB 8500 and the reasons they were sent Good Status Good status indicates that the operation specified by the CDB completed normally For those commands that support the immediate return of status Good status indicates that the EXB 8500 has accepted the command and will attempt to perform the operation specified by the CDB If the specified operation does not complete normally Check Condition status will be reported to the initiator when the next command is received by the EXB 8500 from the same initiator 510201 7 8500 SCSI Command Set Check Condition The EXB 8500 returns Check Condition status 1f an error occurs while it 1s trying execute the command The reporting of Check Condition status is immediate or deferred as follows m If status for the command is to be returned when the command is completed Check Condition status is reported when the error occurs immediate error reporting m If status for the command was returned when the command was initiated that is before the error occurred Check Condition status is reported when the next command is received from the same initiator deferred error reporting m Ifan error occurs while the command is executing and the EXB 8500 is disconnected from the initiator Check Condition status is reported to the initiator after the reconnect process For s
9. Set sense key to Aborted Command Bh Send Message Reject IN l Go to Status phase Set sense key to Send Check Condition Aborted Command Bh Go to Status phase Send Check Condition Figure 6 8 Message Processing during the Data Out Phase of MODE SELECT Command December 1991 6 27 6 SCSI Physical Path Communications 6 28 510201 December 1991 6 SCSI Physical Path Communications Message Processing in Data In Phase READ Command Figure 6 9 shows how messages are processed during the Data In phase of a READ command that is when the initiator asserts the Attention signal while it is receiving user data from the EXB 8500 Note that the EXB 8500 does not allow the physical path characteristics to be altered while it is transferring data this is treated as a catastrophic error committed by the initiator In other words the initiator should not send a Synchronous Data Transfer Request message or the Identify message during data transfer Parity Error in Data Associated with READ Command If the initiator detects a parity error in data transferred from the EXB 8500 during a READ command it should assert the Attention signal This causes the EXB 8500 to stop the data transfer The initiator should then send an Initiator Detected Error message to the EXB 8500 When it receives the Initiator Detected Error the EXB 8500 assumes that a parity error has occurred and aborts the d
10. 19 3 Block Diagram for the Diagnostic Page 19 3 Field Definitions for the Diagnostic Page 19 3 Receiving a Memory Dump 4 6442 40 a4 bee we SR A e wok Bs 19 5 19 3 Receiving a Trace Dump e 9o Rp xS RS ESS OEE 19 6 RELEASE UNIT 17H 20 1 20 1 Field Definitions i5 b X 9 SHE BR OHSS 20 1 REQUEST SENSE 03h v Rx ew 21 1 21 1 Field Demos 39 cece 5908 349 R5 9 3 5 21 1 21 2 Extended Sense Bytes due xc exce e RO RO x Ee ge dos 21 2 Priorities of Sense Bytes cu oa gee Pe eee xou X Ew GS x8 21 11 Sense Byte Pending Status 2 0 424064 vee a ew dow eee n 21 11 RESERVE UNIT 16h x a s ooo REC es we 22 1 Field DREIDOS uuu uos ae aa eS eo aS 22 1 REWIND 01H dx ere e dX we ee we ew Dee o e UC 23 1 23 1 gelu Definitions u sce amp E Eee Bee AE ok 23 2 SEND DIAGNOSTIC 1Dh 2 eco or t RR RR 24 1 24 1 Field Definitions iac d Www e ng EM 24 2 21 2 Diagnostic Tests ss a s Soe See o S08 9 9 9 S ESS 24 3 245 Test Descriptions 2 274 ox dE Wk Rei ob wo x 3S 24 3 Memory Dump up ob xo 3 x 9e X e oe he 24 3 Test
11. The READ POSITION command reports the current position of the EXB 8500 but does not cause tape motion to occur The READ POSITION command is not supported for tapes written in EXB 8200 format and will result in Check Condition status with the sense key set to Illegal Request 5h If the READ POSITION command is issued and there is no data cartridge loaded the EXB 8500 returns Check Condition status with the sense key set to Not Ready 2h The ASC and ASCQ fields are set to 3Ah and 00h 18 1 Field Definitions Byte 01 Bit 0 BT Block Type The BT bit determines the type of block number to be returned to the initiator as follows 0 The SCSI logical block number is returned numbered sequentially from the beginning of the tape 1 An EXABYTE unique block number is returned currently not implemented Byte 09 Bits 7 and 6 Vendor Unique There are no vendor unique definitions for this command December 1991 18 1 18 READ POSITION 34h 18 2 Read Position Data Bit 7 6 5 4 3 2 1 0 Byte 00 BOP EOP Reserved BPU Reserved 01 Partition Number 02 Reserved 03 04 MSB First Block Location 07 LSB 08 MSB Last Block Location 11 LSB 12 Reserved 13 MSB i Number of Blocks in Buffer 15 LSB 16 MSB Number of Bytes in Buffer 19 LSB 18 2 The data returned to the initiator by the READ POSITION command is
12. December 1991 Field Definitions The Read Write Error Recovery Page specifies error recovery parameters used during read write operations These parameters apply only to page format that is when the PF bit in the CDB is set to 1 Byte 00 Bits 5 through 0 Page Code The Page Code identifies the type of MODE SELECT page being transferred This is the Read Write Error Recovery Page The valid value for Page Code is Olh Byte 01 Page Length The Page Length byte indicates the number of bytes in the Read Write Error Recovery Page that follow this byte The valid value for this byte is 07h Byte 02 Bit 5 TB Transfer Block The TB bit is not supported by the EXB 8500 The valid value for this bit is 0 Byte 02 Bit 3 EER Enable Early Recovery The EER bit is not supported by the EXB 8500 The valid value for this bit is O Byte 02 Bit 2 PER Post Error The PER bit is not supported by the EXB 8500 The valid value for this bit is O Byte 02 Bit 1 DTE Disable Transfer on Error The DTE bit is not supported by the EXB 8500 The valid value for this bit is 0 12 17 12 MODE SELECT 15h Byte 02 Bit 0 DCR Disable Correction The DCR bit is not supported by the EXB 8500 The valid value for this bit is 0 Byte 03 Read Retry Count The Read Retry Count field specifies how many times the EXB 8500 should attempt its read recovery algorithms before an unrecoverable read error is reported The Read Retry Coun
13. Figure 6 7 Message Processing during the Data Out Phase of a WRITE Command December 1991 6 25 6 SCSI Physical Path Communications 6 26 Message Processing in Data Out Phase Information Commands Figure 6 8 shows how messages are processed during the Data Out phase for commands other than WRITE for example MODE SELECT Parity Error in Data Out Phase Information Command When parity checking is enabled and the EXB 8500 detects a parity error in the data sent after the MODE SELECT CDB it goes to the Message In phase and sends a Restore Pointers message The initiator must restore the pointer to the start of the data The EXB 8500 then goes to the Data Out phase and requests the data again The initiator should count the Restore Pointers messages received during the Data Out phase to qualify the communication If the count exceeds some threshold the initiator should clear the EXB 8500 from the bus by doing one of the following m Sending the Abort message m Performing a SCSI bus reset m Sending the Bus Device Reset message 510201 6 SCSI Physical Path Communications Initial Phase Data Out Information Command Transition to Message Out for example MODE SELECT Go Bus Free do Execute warm reset Does initiator own current process Abort process Go Bus Free lt _ No Operation Message Reject C Allothers Continue processing
14. D 6 Sense Key 9h EXABYTE uuu aoe RS we Kos D 6 Sense Key Bh Aborted Command 2 222225 o kh D 7 sense Key Dh Volume Overflow zs x x ae he SHEER D 7 Appendix E Fault Symptom Codes E 1 EXB 8500 Error Recovery Procedures 2o y don oes as x WR UE Roxy E 7 85 ME G 1 lip ESET 1 1 December 1991 XV Tables Installing the EXB 8500 Table 2 1 Pin Assignments on the Remote Connector Operating the EXB 8500 Table 3 1 Read and Write Compatibility of EXABYTE 8mm Cartridge Tape Subsystems gt e we ad we Rx EXPE Table 3 2 Type and Size of Filemarks ln Table 3 3 Motion Threshold and Reconnect Threshold Summary Table 3 4 EXB 8500 Configuration Options Table 3 5 EXB 8500 States Indicated by LEDs Table 3 6 Summary of Unload Button Options Cleaning and Packing the EXB 8500 Table 4 1 Environmental Specifications for Shipping the EXB 8500 Loading New Microcode from Tape Table 5 1 Time Required to Load Code from Tape Table 5 2 Time Required to Make a Microcode Update Tape SCSI Physical Path Communications Table 6 1 Messages Supported by the EXB 8500 Table 6 2 EXB 8500 Responses to Attention Signal EXB 8500 SCSI Command Set Table 7 1 EXB 85
15. Figure 2 5 Location of the Four Mounting Holes on the Sides of the EXB 8500 2 8 510201 2 Installing the EXB 8500 SYS Card Cover Figure 2 6 Location of the Four Mounting Holes on the Bottom of the EXB 8500 Refer to the 8500 8mm Cartridge Tape Subsystem Product Specification for detailed information about the locations and dimensions of these mounting holes December 1991 2 9 2 Installing the EXB 8500 2 5 Connecting the EXB 8500 to the SCSI Bus The procedure you use to connect the EXB 8500 to the SCSI bus depends on whether the EXB 8500 uses a single ended or a differential SCSI configuration and whether it terminates the SCSI bus Single Ended SCSI Configuration The single ended SCSI configuration of the EXB 8500 includes two single in line package SIP resistor terminators R packs that can be used if the EXB 8500 terminates the SCSI bus These terminators must be removed if the EXB 8500 does not terminate the SCSI bus or if external SCSI bus termination will be used To remove the R packs follow these steps 1 Locate the two R packs on the back of the EXB 8500 Figure 2 7 shows the location of these R packs labeled RP1 and RP2 Hu SCSI Terminator R Pocks RP1 RP2 x Y N N N N Z Y X NY QNS NN N G CX N N WO N N CS Bine S NS NS SS N N N O ee OK N SN NS WO iN N N WS
16. 1 Any command or activity that is currently in progress is immediately aborted The contents of the buffer are lost No EOD mark is written to the tape to indicate the end of data 2 The tape is unloaded from the tape path without being rewound to the physical beginning of tape PBOT or moved from its current position 3 The EXB 8500 s door is opened and the data cartridge is ejected regardless of whether media removal has been prevented with the PREVENT ALLOW MEDIUM REMOVAL command 4 EXB 8500 is reset CAUTION Since the tape is not rewound when you use the super fast version of the unload button the tape is unloaded from the EXB 8500 at its current position If the unload occurs when the tape is positioned over data tape damage and data loss can occur When you use this feature any data and filemarks in the buffer are lost If the button is pressed while the EXB 8500 is performing a write operation the integrity of the last data written to the tape is questionable and may cause serious errors to occur when you read the tape EXABYTE assumes no liability for data loss occurring when the super fast unload button option is used December 1991 3 19 3 Operating the EXB 8500 Unload Time Table 3 6 summarizes the EXB 8500 s actions for each of the unload button options The time required for each of the actions listed in the table is as follows m The time required to complete the current operation
17. A NN N N bs SN N E N T n Figure 2 7 R Packs on the Back of the EXB 8500 Single Ended SCSI 2 10 510201 2 Installing the EXB 8500 2 Using a pair of flat nose wiring pliers grasp either one of the R packs in the center Be careful not to squeeze the pliers too tightly or you may break the R pack 3 Pull the R pack straight out 4 Remove the remaining R pack in the same manner CAUTION If you replace the R packs be sure to use the correct size and type of terminators Otherwise damage to the EXB 8500 can occur The EXB 8500 uses two 10 pin 9 resistor SIP terminators rated at 110 ohms Replacement R packs are available from EXABYTE part number 002228 In addition when replacing an R pack make sure that pin 1 of the terminator is aligned with pin 1 of the socket and that no pins are bent Differential SCSI Configuration The differential SCSI configuration of the EXB 8500 does not include internal terminators If a differential EXB 8500 terminates the SCSI bus it must be terminated externally Connecting the SCSI Cable After removing or installing terminators as required connect the SCSI cable to the SCSI connector labeled P4 on the back of the EXB 8500 Figure 2 1 shows the location of the SCSI connector See Appendix A for more information about the SCSI cable December 1991 2 11 2 Installing the EXB 8500 2 6 Connecting the EXB 8500 to the Power Suppl
18. Byte 03 Bits 7 through 1 Reserved These bits are reserved Byte 03 Bit 0 WWR Write Without Retries This bit is ignored by the MODE SELECT command It is returned by the MODE SENSE command to indicate whether the tape was written with retries as follows 0 Tape was written with retries 1 Tape was written with retries Bytes 04 and 05 Reserved These bytes are reserved 510201 12 MODE SELECT 15h 12 11 Exceptions and Error Conditions December 1991 The following exceptions and error conditions can occur with the MODE SELECT command Illegal Value in MODE SELECT Data If one of the bytes sent with the MODE SELECT data contains an illegal value or if a reserved bit is set the EXB 8500 returns Check Condition status To determine which byte contains the error issue a REQUEST SENSE command The sense key will be set to Illegal Request 5h and the Fault Symptom Code field byte 28 will indicate which of the consecutively received bytes is in error For example if the Block Descriptor Length field byte 03 in the Parameter List Header is invalid the value for the Fault Symptom Code byte would be 04h Note that the first byte received is byte 1 not byte 0 12 35 12 MODE SELECT 15h 12 12 Tape Format Examples 12 36 This section provides examples for using the EXB 8500 to write append to and read tapes in the following formats m EXB 8200 format m EXB 8500 format As you review and use
19. December 1991 13 3 13 MODE SENSE 1Ah Byte 04 Allocation Length Non Page Format The Allocation Length byte indicates the amount of memory in bytes that the initiator has allocated for the return of MODE SENSE parameters from the EXB 8500 When the Page Code field is set to 0 all parameters after the Block Descriptor are vendor unique and the Allocation Length byte can contain values ranging from 0 to 11h Table 13 2 lists the valid values for the Allocation Length byte when the Page Code is 0 non page format Table 13 2 Allocation Lengths Non Page Format To return these parameters Allocate this length No parameter list data 0 Parameter List Header data 04h Parameter List Header data and 1 to 5 bytes of vendor unique parameters Osh Ooh DIR OON Parameter List Header and Block Descriptor OCh Parameter List Header Block Descriptor and 1 to 5 bytes of vendor unique parameters ODh OEh OFh 10h or 11h Restrictions for MODE SENSE Data in Non Page Format The following restrictions apply to the return of MODE SENSE data in non page format m For any data transfer greater than O bytes the entire 4 byte Parameter List Header must be transferred That is the entire 4 byte Parameter List Header must be transferred before the Block Descriptor or any vendor unique parameters can be transferred m If the Block Descriptor is transferred it must be transferred in its e
20. variable length logical blocks 12 11 Vendor Unique Parameters Page 1 MODE SELECT command 12 29 MODE SENSE command 13 29 Vendor Unique Parameters Page 2 MODE SELECT command 12 34 MODE SENSE command 13 34 vendor unique parameters MODE SELECT command 12 12 MODE SENSE command 13 15 verification length incorrect verify operation 27 5 VERIFY 13h command exceptions errors 27 3 field definitions for 27 1 Vital Product Data Page 9 7 Volume Overflow Dh sense key D 7 W WRITE 0Ah command buffered and unbuffered modes 28 4 exceptions and errors 28 5 field definitions for 28 1 legal tape positions 28 3 WRITE BUFFER 3Bh command 29 1 29 6 write compatibility 3 2 WRITE FILEMARKS 10h command exceptions and errors 30 4 field definitions for 30 1 legal tape positions 30 3 write heads 3 3 Write Tape Format field MODE SENSE command 13 32 write protect switch effect of on WRITE command 28 9 effect of on WRITE FILEMARKS command 30 4 setting 3 14 December 1991 writing tapes examples 12 36 EXB 8200 format 12 36 EXB 8500 format 12 38 WTF field MODE SENSE command 13 32 Index Index l 8 510201 Reader s Comment Form EXB 8500 Cartridge Tape Subsystem User s Manual Part Number 510201 EXABYTE welcomes your comments and suggestions about this manual To let us know how we might make our documentation more helpful please complete and mail this form Rate the following on a scale of 1 to 5 1 very poor
21. 12 MODE SELECT 15h 12 7 Data Compression Page Page CodezOFh Page Format Bit Byte 7 4 00 RSVD Page Code 01 Page Length 02 DCE DCC Reserved 03 DDE RED Reserved 04 MSB Compression Algorithm 07 LSB 08 MSB Decompression Algorithm 11 LSB 12 Reserved 15 Field Definitions The Data Compression Page is used only for page format that is when the PF bit in the CDB is set to 1 This page specifies parameters for the control of data compression Important The EXB 8500 does not support data compression This page is included to enable EXB 8500 drivers to be upwardly compatible with products supporting data compression such as the EXB 8500c Byte 00 Bits 5 through 0 Page Code The Page Code identifies the type of MODE SELECT page being transferred This is the Data Compression Page The valid value for the Page Code is OFh Byte 01 Page Length The Page Length indicates the number of bytes in the Data Compression Page that follow this byte The valid value for this byte is OEh 12 22 510201 December 1991 12 MODE SELECT 15h Byte 02 Bit 7 DCE Data Compression Enable The EXB 8500 does not support data compression so the valid value for the Data Compression Enable bit is 0 Byte 02 Bit 6 DCC Data Compression Capable The Data Compression Capable bit is used by the M
22. 5 fields indicate that a reset occurred m It processes all non motion commands The TEST UNIT READY 00h command returns Check Condition status with the sense key set to Not Ready 2h The ASC and ASCQ fields indicate that no tape is present m Itreturns Check Condition status to all tape motion commands The sense key 15 set to Not Ready 2h and the ASC and 5 fields indicate that no tape is present Note After a reset wait until the green LED turns off before inserting data cartridge into the EXB 8500 December 1991 6 43 7 8500 SCSI Command Set The EXB 8500 supports the SCSI commands listed in Table 7 1 Table 7 1 EXB 8500 Command Set OP Code Command Name 00h 01h 03h 05h 08h OAh 10h 11h 12h 13h 15h 16h 17h 19h 1Ah 1Bh 1Ch 1Dh 1Eh 2Bh 34h 3Bh 3Ch TEST UNIT READY REWIND REQUEST SENSE READ BLOCK LIMITS READ WRITE WRITE FILEMARKS SPACE INQUIRY VERIFY MODE SELECT RESERVE UNIT RELEASE UNIT ERASE MODE SENSE LOAD UNLOAD RECEIVE DIAGNOSTIC RESULTS SEND DIAGNOSTICS PREVENT ALLOW MEDIUM REMOVAL LOCATE READ POSITION WRITE BUFFER READ BUFFER Chapters 8 through 30 contain the detailed descriptions of the SCSI commands supported by the EXB 8500 The commands are listed in alphabetic order with each command starting a new chapter For ease of Discussed in Chapter 26 Chapter 23 Chapter 21 Chapter 16 Chapter 15 Chapter 28 Chapter 30 C
23. If the end of data blank tape is detected during the read operation the EXB 8500 returns Check Condition status The Valid bit is set in the extended sense data with the sense key set to Blank Check 8h When the READ command terminates the logical position is after the last recorded data block or filemark m Ifthe Fixed bit is set to 0 the Information bytes are set to the requested transfer length m Ifthe Fixed bit is set to 1 the Information bytes are set to the difference between the requested transfer length and the actual number of blocks read 15 4 510201 15 READ 08h PEOT Encountered If the physical end of tape PEOT is encountered the EXB 8500 returns Check Condition status The EOM and PEOT bits are set in the extended sense data with the sense key set to Medium Error 3h When the READ command terminates the logical position is not defined If the Valid bit is set to 1 the Information bytes are set to either of the following m The requested transfer length if the Fixed bit is set to 0 m The difference between the requested transfer length and the actual number of blocks read if the Fixed bit is set to 1 Unrecoverable Error If an unrecoverable media or hardware error occurs during the read operation the EXB 8500 terminates the READ command and returns Check Condition status The sense key indicates a Medium Error 3h or Hardware Error 4h Indicators in the extended sense data can be used to
24. and the Additional Sense Code ASC and Additional Sense Code Qualifier ASCQ fields indicate that a reset occurred m It processes all non motion commands The default status returned by the TEST UNIT READY 00h command is Check Condition status with the sense key set to Not Ready 2h The ASC and ASCQ fields indicate that the device is becoming ready 510201 6 SCSI Physical Path Communications Three options are available from EXABYTE to control how the EXB 8500 handles tape motion commands during reset and load operations Depending on the EXB 8500 s EEPROM image the EXB 8500 performs one of the following actions when it receives tape motion commands during a reset or load operation m It queues holds one tape motion command and disconnects if allowed until the reset operation is complete and the tape is loaded Once the load is complete it processes the queued command m Itreturns Busy status m Itreturns Check Condition status with the sense key set to Not Ready If the tape is already rewound when the reset occurs the reset takes about 35 seconds to complete If the tape is positioned toward the end of tape EOT the reset may take as long as 3 minutes to complete Data Cartridge Not Present before Reset When a data cartridge is not present the EXB 8500 responds to the reset as follows m It returns Check Condition status to the first command received The sense key is set to Unit Attention 6h and the ASC and
25. 5 outstanding Is the information specific enough Is the format easy to follow Is the information clear and accurate Are the drawings clear and accurate Comments Please provide the following information Today s Date Company Name Your Title Reader s Comment Form Fold and tape Please Do Not Staple Fold and tape To EXABYTE Corporation Attn Product Documentation 1685 38th Street Boulder CO 80301 Fold and tape Please Do Not Staple Fold and tape EXABYTE
26. All operations have a defined speed that cannot be modified by this command The valid value for this field is 0 Byte 03 Block Descriptor Length This byte contains the length of the Block Descriptor in bytes The EXB 8500 does not support multiple block descriptions The valid values for this byte are 00h and 08h 510201 12 MODE SELECT 15h 12 3 Block Descriptor Non Page and Page Formats Bit Byte 7 6 5 4 2 1 0 00 Density Code 01 02 03 MSB Number of Blocks LSB 04 Reserved 05 06 07 MSB Block Length LSB Field Definitions The Block Descriptor is the same for both non page and page formats Byte 00 Density Code The Density Code field specifies whether the EXB 8500 writes data in EXB 8500 format or EXB 8200 format Table 12 4 on the next page lists the valid values for the Density Code field Note December 1991 Refer to Section 12 12 on page 12 36 for examples for using the EXB 8500 to write read and append to EXB 8200 and EXB 8500 format tapes Refer to page 12 40 in that section if you want to change the Density Code and you cannot issue MODE SELECT commands 12 9 12 MODE SELECT 15h Table 12 4 Values for Density Code Field in MODE SELECT Command Density Format of Data Code Written to Tape Usage Nores Use this Density Code at LBOT if you want to wr
27. EXB 8500 Format Compared to EXB 8200 Format 3 3 3 2 Streaming and Start Stop Modes 2 o 3 7 Moti n Thr shold s 2 1 uou ut ea Pt ax sed dx ay EU EP 9 3e A 3 7 Reconnect Threshold 3 x9 Seow ook Se ee Se Ou wes 3 8 Summary of Motion and Reconnect Thresholds 3 9 3 3 EXB 8500 Directory Support Fe ee de 3 10 3 4 EXB 8500 Configuration Options whee x EUR 3 393 3 11 3 5 EXB 8500 Controls and Indicators 2 22 4 48 4h be xx Ros 3 12 Unload Button 4 22493 m penari xo ox Rey bs RS Heh 3 12 Green and Amber LEDs amp ee o s aoa eS RECO GI v 3 12 3 6 Setting the Write Protect Switch xp x qox Ra SESE SH ES SE 3 14 3 7 Loading a Data Cartridge in EXB 8500 3 15 3 8 Unload Procedure ss s oo eom RE SLEDS 3 16 Unload Button 2 4 e s EPOR OO ODE 30 9 36s 3 16 Unload LIB cu Be bog a aw A oni do Pao 3 20 December 1991 vii Status Reported for Unload Procedure s oso ko 8 3 21 Effect of PREVENT ALLOW MEDIUM REMOVAL Command 3 2 Error During Unload Procedure use og y ees 3 2 4 Cleaning and Packing the EXB 8500 4 1 4 1 Cleaning the EXB 8500 cuu x RU VES 546 ow 9 x E XS 4 4 2 Packing the 8500 for Shipment
28. Immed The Immed bit is used to determine when command status is returned to the initiator 0 Status is reported to the initiator when the LOCATE command 15 completed Status is reported to the initiator when the LOCATE command is initiated by the EXB 8500 If the EXB 8500 buffer contains data from a previous WRITE command and the LOCATE command is in the reverse direction the EXB 8500 disconnects from the initiator 1f disconnect was enabled by the Identify message and writes the data in the buffer to the tape m If the Immed bit is set to 1 the EXB 8500 reconnects to the initiator when the write operation has completed successfully It then returns Good status and performs the locate operation Note Completing the write operation includes emptying the buffer to tape and writing the EOD mark for EXB 8500 format tapes This can take up to 12 seconds m If the Immed bit is set to 0 the EXB 8500 reconnects and returns status when the locate operation is complete 11 2 510201 December 1991 11 LOCATE 2Bh Bytes 03 through 06 Block Address The Block Address field contains the address of the block on which to position Byte 08 Partition The EXB 8500 does not support multiple partitions This field is ignored Byte 05 Bit 7 ADE Always Detect EOD The ADE bit is used only for those EXB 8500s that include the EEPROM image for directory support By setting this bit you can force the EXB 8500 to detect
29. Read directory LBOT MASTER DIR EOD 1 PAD LFM DIR 2 2 Search 510201 Appendix B 8500 Directory Support 1 Issue LOCATE command 3 Once you have found a directory that lists the file you need issue another LOCATE command to reach that file using the READ POSITION data from the directory LBOT MASTER DIR EOD1 PAD LFM December 1991 DS 2 DIR 2 2 Search Appendix B 8500 Directory Support Notes B 10 510201 Appendix C Data Cartridge Capacities This appendix describes how the EXB 8500 autosizes tapes and lists track and physical block counts for the different types and sizes of data cartridges supported by the EXB 8500 It also compares EXATAPE data cartridges with industry standard cartridge sizes and lists the approximate capacities of EXATAPE data cartridges Information is provided for tapes written in EXB 8500 format and in EXB 8200 format Note Refer to the EXB 8500 8mm Cartridge Tape Subsystem Product Specification for detailed information about the recording format for the EXB 8500 including information about recording parameters physical track structure and the logical arrangement of data on the tape Autosizing of Data Cartridges Autosizing is the process that occurs during a load operation when the EXB 8500 spaces forward from the physical beginning of tape PBOT to the logical beginning of tape LBOT and determin
30. Refer to Table 7 1 for a list of SCSI commands in OP code order Refer to Table 7 2 for the hexadecimal values for the returned status Note that the command information in the SCSI instruction trace table is listed in chronological order with information about the most recently issued SCSI command listed last For this reason the RECEIVE DIAGNOSTIC RESULTS 1Ch command that resulted in the trace dump is always listed last F71C at the end of the last line in Figure 19 1 and it does not include a returned status 19 7 19 RECEIVE DIAGNOSTIC RESULTS 1Ch Notes 19 8 510201 20 RELEASE UNIT 17h Bit 7 6 5 4 3 2 1 0 Byte 00 0 0 0 1 0 1 1 1 01 Logical Unit Number 3rdPty Third Party Dev ID RSVD 02 03 Reserved 04 05 Vendor Unique Reserved 0 0 The RELEASE UNIT command releases an EXB 8500 from an initiator s exclusive use or if third party reservations are in effect from another SCSI device s use To have effect the command must be issued by the initiator that reserved the EXB 8500 with a RESERVE UNIT 16h command It is not an error to attempt to release an EXB 8500 that is not currently reserved by the current initiator but if the EXB 8500 is reserved by another initiator then that reservation remains in effect 20 1 Field Definitions December 1991 Byte 01 Bit 4 3rdPty The 3rdPty bit is used to release a third party reserva
31. The EXB 8500 returns Check Condition status after all data in the buffer and the block currently being transferred has been written to tape The extended sense data is set as follows Valid 1 Error Code 70h EOM 1 Sense Key 0h No Sense Information bytes requested transfer length actual number of blocks written to tape LBOT 0 LEOT encountered during previous write operation buffered mode The EXB 8500 returns Check Condition status after all data has been written to tape The extended sense data is set as follows Error Code 70h EOM 1 Sense Key 0h No Sense LBOT 0 The EXB 8500 returns Check Condition status but does not transfer any data The extended sense data is set as follows Valid 1 Error Code 7 1th error associated with previous commana EOM 1 Sense Key 0h No Sense Information bytes requested transfer length ASC and ASCQ 00h 00h LBOT 0 28 6 510201 December 1991 28 WRITE 0Ah Encountering LEOT Because of a Previous WRITE Command To understand how LEOT can be encountered because of a previous WRITE command consider the following hypothetical situation Important If LEOT is encountered as a result of a previous WRITE command the EXB 8500 may write as much as 1 MByte of data after LEOT before reporting this condition this represents the full contents of the buffer As a result the tape may be as much as 1 MByte closer to PEOT than it woul
32. normal unload button default m Asa fast unload button m Asa super fast unload button These three unload button options are described in Section 3 8 on page 3 16 Green and Amber LEDs The green and amber LEDs are status indicators for the EXB 8500 The green LED indicates that the EXB 8500 can accept a tape access command while the amber LED indicates SCSI bus activity and EXB 8500 error conditions 510201 3 Operating the EXB 8500 Table 3 5 describes the EXB 8500 states indicated by the LEDs e The LED is on The LED is off aly E The LED is flashing as follows slow flash is about one flash per second 0 94 Hz A fast flash is about four flashes per second 3 76 Hz Table 3 5 EXB 8500 States Indicated by LEDs When the amber LED is O or O orOor N set AN 5 slow fast 7 Take this corrective action none none none Reset the EXB 8500 by pressing the unload button If this does not clear the error power the EXB 8500 off and back on again If the error occurs again the EXB 8500 needs service Power the EXB 8500 off and back on again If the error occurs again try reloading new code If the error persists the EXB 8500 needs service And the green LED The EXB 8500 state is is Power on initialization Passed power on self test Ready and tape loaded slow Normal tape motion fast High sp
33. the ASC and ASCQ fields are set to 24h and OOh Byte 05 Bit 6 VU Vendor Unique There is no vendor unique definition for this bit 24 2 510201 24 SEND DIAGNOSTIC 1 24 2 Diagnostic Tests Table 24 1 lists the valid combinations of the SelfTest DevOfL UntOfL Parameter List Length and MD fields in the SEND DIAGNOSTIC command and the resulting actions performed by the EXB 8500 Note that all other combinations of settings for these fields are undefined and will result in Check Condition status with the sense key set to Illegal Request Table 24 1 Valid Combinations of SEND DIAGNOSTIC Fields Parameter SelfTest DevOfL UntOfL List Length MD Type of Test 0 0 0 0 to 97FFh 1 Memory dump Test 100 Power on g d 3 0 tests without tape Test 101 Power on 1 0 1 0 0 write read and load tests without tape Test 110 Power on tests with tape Test 111 Power on 1 1 1 0 0 write read and load tests with tape 24 3 Test Descriptions This section describes the memory dump and each type of diagnostic test Memory Dump The memory dump returns the current information from specified locations in the EXB 8500 s memory To perform a memory dump set the SelfTest DevOfL and UntOfL bits to 000 and the MD bit to 1 Specify the starting address for the dump in the Parameter List Length field Then immediately issue a RECEIVE DIAGNOSTIC RESULTS command Specif
34. to use the original shipping materials or replacement materials obtained from EXABYTE when repacking and shipping the EXB 8500 In addition to ensure that the packaging meets the required specifications do not modify the packaging in any way The shipping carton and packing materials are not intended to be used for shipping items other than or in addition to an EXB 8500 Assemble the carton and tape it shut at the bottom Place the bottom packing cushion in the carton with the fitted space for the EXB 8500 facing up Place the EXB 8500 in the bottom packing cushion s fitted space Place the top carton cushion over the EXB 8500 with the cardboard side facing down Close the carton and tape the top seam with two inch packing tape so that the carton is completely closed 510201 4 Cleaning and Packing the EXB 8500 a _ Top A DA Lee Packing 2 PS Cushion e A EXB 8500 Bottom Packing Cushion Figure 4 1 Single Pack Carton and Packing Materials for the EXB 8500 Environmental Requirements for Shipping the EXB 8500 When shipping an EXB 8500 be sure to comply with the environmental specifications shown in Table 4 1 Table 4 1 Environmental Specifications for Shipping the EXB 8500 Temperature Range 40 C to 60 40 F to 140 F 1 C per minute up to a maximum of 20 C per hour Temperature Varian 2 F per minute up to a maximum of 36 F per hour Relative Humidity 10 to 90 no
35. 01 Logical Unit Number Reserved Immed Long 02 03 Reserved 04 05 Vendor Unique Reserved 0 0 The ERASE command causes the EXB 8500 to erase all tape from the current valid tape position to the physical end of tape PEOT When the erase operation is successfully completed the tape is automatically rewound to the logical beginning of tape LBOT Notes m Ifthe disconnect option is enabled the EXB 8500 disconnects from the initiator while the ERASE command is executing m Ifthe ERASE command is received after a WRITE 0Ah or WRITE FILEMARKS 10h command buffered data and filemarks are written to tape before the erase operation is performed m Ifan error occurs during the writing of the data in the buffer to the tape the EXB 8500 returns Check Condition status The erase operation is not performed The initiator should issue a REQUEST SENSE 03h command to determine the cause of the error The ERASE command performs the erase operation at the same speed as the READ and WRITE commands are performed for example starting at LBOT a 5 GByte data cartridge will take approximately two hours to erase December 1991 8 1 8 ERASE 19h 8 1 Field Definitions 8 2 Byte 01 Bit 1 Immed The Immed bit is used to determine when command status is returned to the initiator as follows 0 Status is reported to the initiator when the ERASE command is completed Status is reported to the initiator w
36. 132 ohms single ended However since cables with this high of a characteristic impedance are not generally available somewhat lower impedances are acceptable A characteristic impedance of 100 ohms 10 is recommended for unshielded flat or twisted pair ribbon cable A characteristic impedance greater than 90 ohms is recommended for shielded cables Note To minimize discontinuities and signal reflections ensure that cables used on the same bus have the same impedances A minimum conductor size of 28 AWG is recommended to minimize noise effects and ensure proper distribution of terminator power December 1991 A 3 Appendix A Cable Requirements Table A 1 shows the recommended general specifications for the cable Table A 1 Specifications for the SCSI Cable Standard Construction 50 conductor 25 twisted pairs Primary Conductors 28 AWG minimum Fast Synchronous Data Transfer Signal Attenuation Less than 6 dB per 100 feet 0 095 dB max per meter at 5 MHz Pair to pair Propagation Delay Delta 0 20 nanoseconds maximum per meter DC Resistance 0 230 ohms maximum per meter at 20 C Cables for Differential SCSI Configurations For differential SCSI configurations use a 50 conductor flat cable or 25 signal twisted pair bus Ensure that the length of the cable does not exceed 25 0 meters 82 02 feet A stub length of no more than 0 2 meters 8 inches is allowed off the mainline interconnection within any connected equipme
37. 1991 30 1 30 WRITE FILEMARKS 10h 30 2 Bytes 02 through 04 Number of Filemarks The Number of Filemarks field specifies the number of filemarks to be written to tape A value of 0 for the Number of Filemarks field is not an error and results in either of the following m If the value for the Number of Filemarks field is 0 and the Immed bit is set to 0 no filemarks are transferred and the data in the buffer is written to the tape m If the value of the Number of Filemarks field is 0 and the Immed bit is set to 1 no operation is performed and Good status is returned Byte 05 Bit 7 Short The Short bit determines the size of the filemark written to tape by the EXB 8500 as follows m If the EXB 8500 is writing information in EXB 8500 format set the Short bit to 0 to write an EXB 8500 long filemark 48 KBytes Set the Short bit to 1 to write an EXB 8500 short filemark 1 KByte m Ifthe EXB 8500 is writing information in EXB 8200 format set the Short bit to 0 to write an EXB 8200 long filemark 2 160 KBytes Set the Short bit to 1 to write an 82005 short filemark 184 KBytes Refer to Table 3 2 for more information about long short and 82005 short filemarks Byte 05 Bit 6 VU Vendor Unique There are no vendor unique definitions for this bit 510201 30 WRITE FILEMARKS 10h 30 2 Tape Positioning December 1991 This sections describes the legal tape positions for a write filemarks operati
38. 3 11 6 3 6 42 December 1991 Index PREVENT ALLOW MEDIUM REMOVAL 1Eh command effect of on LOAD UNLOAD command 14 2 effect of on unload button 3 21 14 2 field definitions for 14 1 R R packs 2 10 READ 08h command exceptions and error conditions 15 4 field definitions for 15 2 READ BLOCK LIMITS 05h command 16 1 16 2 read block limits data 16 2 READ BUFFER 3Bh command 17 1 17 2 read compatibility 3 2 read heads 3 3 READ POSITION 34h command described 18 1 18 4 using for directory support 1 B 10 Read Position Data 18 2 Read Tape Format field MODE SENSE command 13 31 Read Write Error Recovery Page MODE SELECT command 12 17 MODE SENSE command 13 19 reading tapes examples 12 36 EXB 8200 format 12 36 EXB 8500 format 12 38 RECEIVE DIAGNOSTIC RESULTS 1Ch command Diagnostic Page 19 3 field definitions for 19 2 receiving a memory dump 19 5 receiving a trace dump 19 6 reconnect threshold described 3 8 setting with Buffer Empty and Buffer Full Ratios page format 12 20 setting with MODE SELECT non page format 12 15 summary of 3 9 RELEASE UNIT 17h command remote connector 2 6 remote switch for setting SCSIID 2 5 REQUEST SENSE 03h command ASC field 21 6 D 1 ASCQ field 21 6 D 1 extended sense bytes 21 2 Fault Symptom Codes 21 10 E 1 E 8 field definitions for 21 1 sense key definitions 21 3 D 1 D 8 unit sense bytes 21 7 20 1 20 2 Index reselection 6 34 Reservat
39. 510201 19 RECEIVE DIAGNOSTIC RESULTS 1 Format of SCSI Instruction Trace Table As shown in Figure 19 1 the first 256 bytes of the trace dump include information about SCSI commands that have been issued to the EXB 8500 000000000000000000000000F700E702F712E700F716E700F71AE700F715E700 F701E700F70AE700F710E700F70AE700F70AE700F70AE700F70AE700F710E700 F717E700F600E602F6 1 AE600F616E600F60AE600F60AE600F60AE600F60AE600 F60AE600F60A E600F60AE600F60A E600F60AE600F6 1 7E600F400E402F4 1 2E400 F416E400F401E400F408E400F408E402F408E400F408E400F7 16E700F7 1 DE700F71C Figure 19 1 Example SCSI Instruction Trace Table December 1991 Eight hexadecimal characters four bytes are returned for each command The first two characters or Indicate the SCSI ID n of the host first byte Fn issuing the command The second two characters or Indicate the command s OP code in second byte hexadecimal form The third two characters or Indicate the SCSI ID n of the host third byte En receiving the returned status The final two characters or Indicate the returned status in fourth byte hexadecimal form In the example shown in Figure 19 1 F700E702 on the first line indicates that host 7 F7 issued a TEST UNIT READY command OP code 00h and received Check Condition status 02h Similarly F416E400 at the beginning of the fifth line indicates that host 4 issued a RESERVE UNIT command OP code 16h and received Good status Note
40. 8500 does not claim compliance with the ECMA standards Byte 02 Bits 2 through 0 ANSI Version The value returned for this field 1s 2h which indicates that the EXB 8500 supports the current version of the ANSI SCSI 2 standard X3T9 89 042 Byte 03 Bit 7 AENC The value returned for this field is 0 which indicates that the EXB 8500 does not support the AENC bit 510201 December 1991 9 INQUIRY 12h Byte 03 Bit 6 TrmlOP The value returned for this field is 0 which indicates that the EXB 8500 does not support the Terminate I O Process message Byte 03 Bits 3 through 0 Response Data Format value returned for this field is 2h which indicates that the data found 15 in accordance with the ANSI SCSI 2 standard Byte 04 Additional Length The value returned for this field is 65h which indicates that there are 65h 101 additional bytes of Inquiry data available to be returned to the initiator These bytes are defined as follows Byte 05 and 06 Reserved These bytes are reserved Byte 07 Bit 7 RelAdr The value returned for this field is 0 which indicates that the EXB 8500 does not support relative addressing RelAdr Byte 07 Bit 6 WBus32 The value returned for this field is 0 which indicates that the EXB 8500 does not support 32 bit wide bus transfers Byte 07 Bit 5 WBus16 The value returned for this field is 0 which indicates that the EXB 8500 does not support 16 bit wide bus transfers
41. 8500 can store up to 5 0 gigabytes of data on a single 8mm data cartridge 8500 The EXB 8500c 8mm Cartridge Tape Subsystem The EXB 8500c is very similar to the EXB 8500 but offers data compression as an option Assuming a 2 1 data compression ratio the EXB 8500c can store up to 10 0 gigabytes of data on a single 8mm data cartridge EXB 8500 format One of two data formats written and read by the EXB 8500 Tapes written by the EXB 8500 in EXB 8500 format can be read by the EXB 8500 and EXB 8500c but cannot be read by the EXB 8200 EXB 8200SX or EXB 8205 See also EXB 8200 format F Fahrenheit FCC Federal Communications Commission GByte Gigabyte or one billion bytes h Hexadecimal base 16 numbering system host The computer system that acts as the initiator of an operation Hz Hertz G 2 510201 ID IEC initiator KByte LBOT LEOT LSb LSB LUN MByte mm motion threshold ms or msec MSb MSB ns NSTA PBOT PEOT ready December 1991 Glossary Identification International Electrotechnical Commission A host computer system that requests an operation to be performed by a target Kilobyte or 1 024 bytes Logical beginning of tape Logical end of tape Sometimes referred to as early warning Least significant bit Least significant byte Logical unit number Megabyte or one million bytes Millimeter 0 03937 inches During a start stop write operation the minimum amount
42. 8500 is sealed in a static protection bag and is shipped with either one drive per carton single pack or four drives per carton four pack The shipping cartons and internal packing materials are designed so that an enclosed EXB 8500 does not receive a shock greater than 45 g when the carton is dropped on any surface corner or edge from the following heights m 48 inches 121 9 cm at a velocity change of 192 inches per second 488 cm sec for the single pack carton m 36 inches 91 4 cm at a velocity change of 167 inches per second 424 cm sec for the four pack carton Both sizes of shipping carton pass the tests described in the National Safe Transit Association NSTA Project 1A for packaged products weighing less than 100 pounds The single pack shipping carton measures 15 inches long x 12 inches wide x 10 inches high 38 x 32 x 26 Note Do not use four pack shipping carton when shipping a single EXB 8500 If you use a four pack shipping carton you must place four EXB 8500 in the carton December 1991 4 3 4 Cleaning and Packing the EXB 8500 Packing the EXB 8500 To pack the EXB 8500 for shipment follow these steps 1 4 4 Obtain the original single pack shipping carton contact your regional account representative to receive a new one Figure 4 1 shows the single pack shipping carton and packing materials for the EXB 8500 CAUTION To avoid damaging the EXB 8500 and voiding your warranty be sure
43. 8500 s directory support feature The application uses the READ POSITION 34h and LOCATE 2Bh commands to implement directory support but you can use the SPACE 11h command as well Note The EXB 8500 directory support feature 15 an option requiring a special EEPROM image available from EXABYTE This EEPROM image is not included in standard EXB 8500s Overview of EXB 8500 Directory Support The sample application in this appendix shows one method for creating a tape that uses the EXB 8500 s directory support feature Figure B 1 shows how the information will be arranged on a tape that was created using this method LBOT MASTER DIR EOD1 PAD LFM 51 DIR1 D5n DIR n 2 Figure B 1 Typical Arrangement of Information on a Directory Support Tape The components in Figure B 1 are as follows m LBOT is the logical beginning of tape m MASTER DIR is the master directory for the tape The master directory contains data from READ POSITION commands that points to the locations of other directories on the tape m EOD 1 is the first end of data mark on the tape This EOD is automatically written at the end of the master directory when you rewind the tape to LBOT m PAD is an area on tape that accounts for the space required to create and update the master directory m LFMisalong filemark separating the master directory and pad space from the data sets written
44. A 6 terminators 2 1 sizing of data cartridges See autosizing SPACE 11h command exceptions and errors 25 3 field definitions for 25 2 using for directory support Standard Inquiry Data 9 3 start stop mode of operation 3 7 status byte 7 7 Status In phase 6 32 streaming mode of operation 3 7 super fast unload option 3 19 Synchronous Data Transfer Request message described 6 5 processing 6 20 6 22 T B 1 B 10 tape format EXB 8500 compared to EXB 8200 3 3 setting with MODE SELECT command 12 9 tape positions for appending data 28 3 for appending filemarks 30 3 terminators for SCSI bus external 2 1 internal 2 10 TEST UNIT READY 00h command tests performed by SEND DIAGNOSTIC command 24 3 threshold See gap threshold See motion threshold See reconnect threshold trace dump 19 6 track structure EXB 8200 format 3 4 EXB 8500 format 3 3 transfer length incorrect read operation 15 6 U unbuffered write operation 28 4 Unit Attention 6h sense key ASC and ASCQ values for D 6 clearing 6 39 conditions causing 6 38 effect of changing data cartridges 6 38 unit sense bytes 21 7 26 1 26 2 510201 Unit Serial Number Page 9 8 unload button action performed by 3 16 effect of PREVENT ALLOW MEDIUM REMOVAL command 3 21 14 2 location of 3 12 options for 3 16 UNLOAD command See LOAD UNLOAD 1Bh command unload procedure described 3 16 status reported during 3 21 time required for 3 20 unpacking instructions 2 2 V
45. BUFFER commands as follows m If you using only one WRITE BUFFER command to download new microcode specify exactly 2AE28h 175 656 bytes for the Parameter List Length m If you are using more than one WRITE BUFFER command to download new microcode specify a multiple of 400h for each Parameter List Length must be greater than 0 Be sure to set the WBF bit to 1 Then for the last WRITE BUFFER command in the sequence set the Parameter List Length to the remaining length that is set it to 2AE28h minus the total of the previous Parameter List Lengths Set the WBF bit to 0 Note The Parameter List Length for the last WRITE BUFFER command does not need to be a multiple of 400h but it must be greater than 0 Byte 09 Bit 7 WBF WRITE 5 Follow The WBF bit specifies whether the new microcode is being sent using one more WRITE BUFFER commands as follows 0 This is the only WRITE BUFFER command or this is the last WRITE BUFFER command in a sequence This 15 one of several but not the last WRITE BUFFER commands in a sequence For each setting of the WBF bit the Parameter List Length field bytes 06 08 specifies the number of bytes to be transferred by the current command Byte 09 Bit 6 VU Vendor Unique There is no vendor unique definition for this bit This bit must be 0 510201 29 WRITE BUFFER 29 2 Exceptions and Error Conditions The following exceptions and error conditions c
46. Block Length the EXB 8500 returns Check Condition status with the sense key set to Illegal Request 5h m If the value specified for the Block Length field is not divisible by 4 or 2 if the EEPROM image is set for two byte boundary disconnect then even byte disconnect is disabled when the EXB 8500 updates the logical block length m For information about changing the power on default for the block length refer to Section 3 4 12 11 12 MODE SELECT 15h 12 4 Vendor Unique Parameters Non Page Format Bit 7 6 5 4 3 2 1 0 Byte 00 CT RSVD ND RSVD NBE EBD PE NAL 01 Reserved P5 02 Motion Threshold 03 Reconnect Threshold 04 Gap Threshold 12 12 Field Definitions These vendor unique parameters apply only to non page format that is when the PF bit in the CDB is set to O Byte 00 Bit 7 CT Cartridge Type This bit defines what type of data cartridge is expected to be loaded as follows 0 P6 Cartridge Type Domestic PI Cartridge Type International P5 P6 LEOT equivalency Note You can set the CT bit only when the tape is positioned at LBOT Refer to Appendix C for information about data cartridge capacities and for an explanation of how the EXB 8500 autosizes data cartridges For information about changing the power on default for the cartridge type refer to Section 3 4 Byte 00 Bit 6 RSVD This bit is reserved 510201 12 MODE
47. Byte 07 Bit 4 Sync The value returned for this field is 1 which indicates that the EXB 8500 supports synchronous data transfer Byte 07 Bit 3 Linked The value returned for this field is 0 which indicates that the EXB 8500 does not support linked commands Byte 07 Bit 2 RSVD This bit is reserved Byte 07 Bit 1 CmdQue The value returned for this field is 0 which indicates that the EXB 8500 does not support tag command queuing Byte 07 Bit 0 SftRe The value returned for this field is 0 which indicates that the EXB 8500 does not support the soft reset alternative in response to a reset condition 9 5 9 INQUIRY 12h 9 6 Bytes 08 through 15 Vendor Identification The value contained in these bytes are the ASCII representation of EXABYTE followed by a single space Bytes 16 through 31 Product Identification The values contained in these bytes are the ASCII representation of the product name followed by a space and the default configuration identifier for example EXB 8500 85QANXRO Bytes 32 through 35 Product Revision Level The values contained in these bytes are the ASCII representation of the revision level for example 1000 or other EXABYTE revision levels Bytes 36 through 55 Vendor Specific The values contained in these bytes are the ASCII representation of blanks The values for these bytes may be customized for specific OEM requirements Bytes 56 through 95 Reserved These by
48. Byte 12 Byte 13 Explanation FSC 04h 00h Logical unit not ready Cause unknown C6h C8h 04h Oth Logical unit not ready but is in process of becoming ready C7h rewinding or loading tape 3Ah 00h Logical unit not ready Command requires a tape and no tape is C9h present D 2 510201 Appendix D Sense Key Information Sense Key 3h Medium Error ASC ASCQ Related Byte 12 Byte 13 00h 02h PEOT was encountered during a space or locate operation 34h 96h 97h 03h 02h Excessive write errors 9Dh 9Fh B3h 09h 00h _ Tracking error AEh OCh 00h LBOT failure unable to write tape marks tracks in EXB 8200 mode 1h 00h An uncorrectable block was encountered during a read space or 37h B5h locate operation 11h 01h Anuncorrectable block was encountered during a read operation OBh 11h 03h Too many permanent read errors can t sync 11h 14h 00h A Medium Error was detected during a read space or locate 16h 38h operation Parameter not supported The boot code did not allow a load from 26h 01h 66h tape or the code version was not supported by the boot code 26h 02h JA write buffer parameter value was invalid The data on the tape is compressed but the hardware cannot 30h 00h decompress it Note This error is included for upward compatibility 1Ch with products that support data compression 31h 00h A tape format error was e
49. EXB 8500 does not support data compression so the value returned for this bit is 0 Note The initiator can use the setting of this bit to determine if the device is an EXB 8500 DCC 0 or an EXB 8500c DCC 1 Byte 02 Bits 5 through 0 Reserved These bits are reserved Byte 03 Bit 7 DDE Data Decompression Enable The EXB 8500 does not support data decompression so the value returned for the Data Decompression Enable bit is 0 Byte 03 Bits 6 and 5 RED Report Exception on Decompression The EXB 8500 does not support data decompression so the value returned for the Report Exception on Decompression field is 00 Byte 03 Bits 4 through 0 Reserved These bits are reserved Bytes 04 through 07 Compression Algorithm The value returned for the Compression Algorithm field is 0 Bytes 08 through 11 Decompression Algorithm The value returned for the Decompression Algorithm field is 0 Bytes 12 through 15 Reserved These bytes are reserved 510201 13 MODE SENSE 13 8 Device Configuration Page Page Codez10h Bit 7 6 5 4 3 2 1 0 Byte 00 Reserved Page Code 01 Page Length 02 RSVD CAP CAF Active Format 03 Active Partition 04 Write Buffer Full Ratio 05 Read Buffer Empty Ratio 06 MSB Write Delay Time 07 LSB 08 DBR BIS RSmk AVC SOCF RBO REW 09 Gap Size 10 EOD Defined EEG SEW Reserved 11 MS
50. GROUND Appendix A Cable Requirements Table A 3 Connector Pin Assignments for Single ended EXB 8500s Signal Pin Number DB 0 2 DB 1 4 DB 2 6 DB 3 8 DB 4 10 DB 5 12 DB 6 14 DB 7 16 DB P 18 GROUND 20 GROUND 22 GROUND 24 TERMPWR 26 GROUND 28 GROUND 30 ATN 32 GROUND 34 BSY 36 ACK 38 RST 40 MSG 42 SEL 44 C D 46 REQ 48 l O 50 All odd pins except pin 25 are connected to ground Pin 25 is left open A 6 510201 Appendix A Cable Requirements Requirements for the Power Cable Connector December 1991 The power connector used in the EXB 8500 is compatible with the power connector used for standard 5 25 inch devices To connect the EXB 8500 to a power cable use an AMP 1 480424 0 series or equivalent female connector Table A 4 lists the pin assignments for the EXB 8500 s power connector AMP 641737 1 Table 4 Pin Assignments for the EXB 8500 Power Connector Pin No Assignment 1 12 VDC 2 Ground 12 VDC return 3 Ground 5 VDC return 4 5 VDC A 7 Appendix A Cable Requirements Notes A 8 510201 Appendix B 8500 Directory Support The EXB 8500 s directory support feature enables you to maintain a directory that indicates where various data sets are located on the tape You can use this directory to find out what data is on the tape and to locate that data quickly and efficiently The sample application in this appendix provides information about using the EXB
51. In phase and sends a Restore Data Pointers message Then the EXB 8500 transitions to the Command Out phase and tries to process the CDB again If this retry process occurs 15 times 16 times total the EXB 8500 goes to Status phase and returns Check Condition The sense key is set to Aborted Command Bh and the ASC and ASCQ are set to 43h and 00h The FSC is set to EOh CDB Processing Receive byte 00 of CDB Is the Group Code valid Set sense key to Invalid Op Code Yes Get 5 or 9 more Go to Status phase CDB bytes Send Check Condition Figure 6 3 Processing of CDB Bytes December 1991 6 17 6 SCSI Physical Path Communications Message Processing in the Message Out Phase after Command Phase Figure 6 4 shows how messages are processed after the Command phase and before any Data phase This processing is the same as that in Figure 6 2 Message sequences that are legal before the CDB is received are also legal after the CDB is received Parity Error in the Message Out Phase When parity checking is enabled and the EXB 8500 detects a parity error in a message received from the initiator the EXB 8500 goes to the Message Out phase again to request that the initiator reissue the message 6 18 510201 6 SCSI Physical Path Communications Initial Phase Message Out Transition to Message Out Identify Is Disconnect bit set Does initiator own current Yes process Allow disconnects
52. N IO Ph Insert a data cartridge into the EXB 8500 Perform one of the following actions m Power the EXB 8500 off and back on again m Senda SCSI bus reset hard reset Clean the EXB 8500 and repeat the operation 10 No action is necessary User should determine what recovery procedure to follow 12 The EXB 8500 requires maintenance 1 Perform one of the following actions m Issue a REWIND SPACE LOAD UNLOAD or LOCATE command m Press the unload button m Power the EXB 8500 off and back on again m Send a SCSI bus reset hard reset 2 Reissue the failed command or command sequence Repeat the operation with a different data cartridge the EXB 8500 cannot read the tape Reprogram the EEPROM E 7 Appendix E Fault Symptom Codes Notes E 8 510201 Glossary address ATN b BOT BSY bus devices byte C CDB cm connect CRC CSA disconnect early warning ECC EEPROM EPROM EOD EOM EOT December 1991 A unique identifier assigned to each device or subsystem on the SCSI bus Also referred to as the SCSI ID Attention signal This SCSI bus signal is asserted by the initiator to indicate that it has a message to transmit to the target Binary base 2 numbering system Beginning of tape Busy bus condition Initiator or target devices connected to the SCSI bus Eight bits or one character Celsius Centi
53. Phase before reporting this error 27 4 510201 27 VERIFY 13h Verification Length Incorrect If the actual verification length does not match the requested verification length the information reported depends on the setting of the Fixed bit Variable Length Mode If the Fixed bit is set to O and the actual length of the block on the tape does not match the verification length requested the EXB 8500 verifies the number of bytes available up to the verification length requested Then the EXB 8500 terminates the VERIFY command and returns Check Condition status The Illegal Length Indicator ILI bit and the Valid bit are set in the extended sense data with the sense key set to No Sense The Information bytes indicate the difference between the actual and the requested lengths as follows m If the requested length is greater than the actual length the Information bytes are positive m If the requested length is less than the actual length the Information bytes are negative 2s complement notation Fixed Length Mode If the Fixed bit is set to 1 and the actual length of any one block does not match the requested block length the EXB 8500 verifies the number of blocks requested until it encounters the block with the incorrect length Then the EXB 8500 terminates the VERIFY command and returns Check Condition status The Illegal Length Indicator ILD bit and the Valid bit are set in the extended sense data with the sense key set
54. Reconnect Threshold byte is set to a value less than AOh or greater than COh it will be changed to AOh This is necessary for proper buffer management Byte 00 Bit 4 RSVD This bit is reserved Byte 00 Bit 3 NBE No Busy Enable This bit is included for EXB 8200 compatibility only This bit is set to 1 in the MODE SENSE data and is ignored by the MODE SELECT command December 1991 12 13 12 MODE SELECT 15h 12 14 Byte 00 Bit 2 EBD Even Byte Disconnect This bit is used to enable disconnects on even byte boundaries Two options are available from EXABYTE to control what happens when the EBD bit is set to 1 Depending on EXB 8500 s EEPROM image setting the EBD bit to 1 allows disconnects to occur on two byte boundaries or on four byte boundaries 0 Disconnect on any byte Disconnect on even byte two byte or four byte boundaries Notes m Ifthe logical block length specified by the Block Length field in the Block Descriptor is not divisible by 4 or 2 if the EEPROM image is set for two byte boundary disconnect setting the EBD bit to 1 causes the EXB 8500 to return Check Condition status with the sense key set to Illegal Request 5h m For information about changing the power on default for even byte disconnect refer to Section 3 4 Byte 00 Bit 1 PE Parity Enable This bit is used to enable parity checking on the SCSI bus When this bit is set to 1 every byte received by the EXB 8500 is checked for
55. SCSI bus and the input power the EXB 8500 will continue to operate without error when subjected to moderate levels of electromagnetic energy as defined by the following standard m IEC Publication 801 3 Severity Level 3 Other Test Standards When shipped the EXB 8500 is packaged in a manner that complies with the testing criteria defined by the following standard m National Safe Transit Association NSTA Project 1 1 General Information Notes 1 8 510201 2 Installing the EXB 8500 This chapter describes how to install the EXB 8500 Installing the EXB 8500 involves unpacking it setting the SCSI ID attaching the drive to a mounting frame if desired connecting it to the SCSI bus connecting it to a power supply and performing the initial power on Although you can perform some of these tasks in any order this manual presents these tasks in the order you will typically follow Note For information about the cable requirements for the EXB 8500 refer to Appendix A For details about the power specifications and environmental conditions required for the EXB 8500 refer to the 8500 8mm Cartridge Tape Subsystem Product Specification 2 1 Required and Optional Equipment December 1991 To install the EXB 8500 the following equipment is required m ASCSIcable with sufficient connectors attached to operate the desired number of EXB 8500s Note The SCSI cable is not provided with the EXB 8500 Refer to Appendix
56. Servo system detected an error Byte 20 Bit 0 FE Formatter Error Catastrophic hardware error Data formatter detected an error Byte 21 Bits 7 through 6 RSVD These bits are reserved Byte 21 Bit 5 RRR Reverse Retries Required This bit is set to 1 when the EXB 8500 is forced to invoke retries in order to move the tape properly It is reset to 0 when a new tape is loaded 510201 21 REQUEST SENSE 03h Byte 21 Bit4 CLND This bit is setto 1 when the EXB 8500 has been cleaned It is reset to 0 when the next REQUEST SENSE command is received Byte 21 CLN This bit is set to 1 when it is time to clean the EXB 8500 It is reset to when a successful cleaning cycle is performed Byte 21 Bit 2 PEOT Physical End of Tape If the cartridge is at PEOT this bit is set for any REQUEST SENSE command Byte 21 Bit 1 WSEB Write Splice Error Write splice error Encountered blank tape when trying to splice Hardware error Byte 21 Bit 0 WSEO Write Splice Error Write splice error Overshot position when trying to splice Hardware error Byte 22 Reserved This byte is reserved Bytes 23 through 25 Remaining Tape The Remaining Tape field indicates the amount of tape remaining in 1 024 byte physical blocks This is the LEOT position minus the current physical position If the position is past the LEOT the value is negative indicating the number of physical blocks past LEOT If there is no data ca
57. Subsystem 1 4 Installing the EXB 8500 Figure 2 1 Connectors and Controls on the Back Panel of the 8500 2 4 Figure 2 2 DIP Switch Settings for the EXB 8500 s SCSIID 2 5 Figure 2 3 Location of the Pins on the Remote Connector 2 6 Figure 2 4 Jumper Connections for the EXB 8500 s SCSIID 2 7 Figure 2 5 Location of the Four Mounting Holes on the Sides of the EXB 8500 2 8 Figure 2 6 Location of the Four Mounting Holes on the Bottom of the EXB 8500 2 9 Figure 2 7 R Packs on the Back of the EXB 8500 Single Ended SCSI 2 10 Operating the EXB 8500 Figure 3 1 EXB 8500 Front Panel llle 3 12 Figure 3 2 Write Protect Switch on EXATAPE 8mm Data Cartridge 3 14 Cleaning and Packing the EXB 8500 Figure 4 1 Single Pack Carton and Packing Materials for the EXB 8500 4 5 SCSI Physical Path Communications Figure 6 1 Message Processing after the Selection Phase 6 14 Figure 6 2 Message Out Bytes Received after Previous Message Out Phase 6 16 Figure 6 3 Processing of CDB Bytes 22s RS RA 6 17 Figure 6 4 Message Processing after the Command Phase and before the Data In ir TP 6 19 Figure 6 5 Message Processing of Extended Message Out Bytes 6 21 Figure 6 6 Message Processing for Synchronous Data Transfer Request Message 6 23 Figure
58. The sense key is set to Aborted Command Bh and the ASC and ASCQ bytes are set to 47h and 00h The SCSI Bus Parity Error BPE bit is set to 1 m If you are attempting to write a variable length block you may be able to recover by reissuing the WRITE command an unlimited number of times Each time a failure is detected the EXB 8500 returns Check Condition status m If you are attempting to write fixed length blocks you may be able to recover by following these steps 1 Issue a REQUEST SENSE command 2 Look at the Information Bytes to determine how many fixed blocks need to be re sent These bytes indicate how many logical blocks were not transferred successfully including the logical block with the parity error 3 Adjust the initiator s data pointer to reflect the number of blocks that were successfully transferred 4 Issue WRITE command to re send the blocks that were not successfully transferred 6 24 510201 6 SCSI Physical Path Communications Initial Phase Data Out Transition to Message Out write data to tape Does No initiator own current process Execute warm reset Abort process Go Bus Free No Operation Set sense key to Aborted Command Bh Abor proc ss Go to Status phase Send Message Reject IN m EE RENI Set sense key to Aborted Command Bh Go to Status phase Send Check Condition
59. Unique Parameters Page 2 Page Code 21h 12 5 12 MODE SELECT 15h Restrictions for MODE SELECT Data in Page Format The following restrictions apply to transfers of parameter list data when the PF bit is 1 m For any data transfer greater than O bytes the entire 4 byte Parameter List Header must be transferred That is the entire 4 byte Parameter List Header must be transferred before the Block Descriptor or any parameter page can be transferred m The Block Descriptor and any parameter pages must be transferred in their entirety partial transfers of these data segments are not allowed Note Any value for the Parameter List Length that causes the Parameter List Header Block Descriptor or one of the parameter pages to be truncated will terminate the command with Check Condition status The sense key will be set to Illegal Request and the Additional Sense Code will be set to Parameter List Length Error m Various combinations of the Parameter List Header Block Descriptor and parameter pages can be transferred based on these restrictions Byte 05 Bits 7 and 6 Vendor Unique There are no vendor unique definitions for these bits 12 6 510201 12 2 Parameter List Header Non Page and Page Formats 12 MODE SELECT 15h Bit 7 6 5 4 3 1 0 Byte 00 Reserved 01 02 RSVD Buffered Mode Speed 03 Block Descriptor Length Field Definitions The Paramet
60. a negative number 2s complement notation 510201 25 SPACE 11h Unrecoverable Error If an unrecoverable media or hardware error occurs during the space operation the EXB 8500 terminates the SPACE command and returns Check Condition status The sense key indicates a Medium Error 3h or Hardware Error 4h Indicators in the extended sense data can be used to isolate the error condition When the SPACE command is terminated the position of the EXB 8500 depends on whether a forward or backward space was attempted m Ifthe error occurred during a forward space the EXB 8500 is positioned after the unrecovered block m Ifthe error occurred during a backward space the EXB 8500 is positioned before or after the unrecovered block If the Valid bit is set to 1 the Information bytes indicate the difference between the requested number of blocks or filemarks and the actual number of blocks or filemarks spaced over The actual length does not include the unrecovered block Note that the Information bytes may be positive or negative Illegal Requests The following conditions cause the EXB 8500 to return Check Condition status with the sense key set to Illegal Request 5h m A forward space is attempted immediately after a WRITE or WRITE FILEMARKS command has been executed m A space to EOD is attempted on a tape written in EXB 8200 format 25 3 Spacing to EOD If the tape is written in EXB 8500 format and the Code field has a v
61. amount for the Allocation Length of Length To return this page page in if DBD 0 if DBD 1 seen return 8 byte Block do not return 8 byte Descriptor Block Descriptor Read Write Error Recovery Page Page Code 01h 949 n apn Disconnect Reconnect Page Page Code 02h 12 Ch 18h 10h Data Compression Page Page Code 0Fh 16 10h 1Ch 14h Device Configuration Page Code 10h TSE n ud Vendor Unique Parameters Page 1 Page Code 20h oe Ten oan Vendor Unique Parameters Page 2 Page Code 21h 10 UAR All six available pages Page 64 40h 4Ch 44h The transfer must include the 4 byte Parameter List Header 13 6 510201 13 MODE SENSE Examples To return the Parameter List Header the Block Descriptor and the Vendor Unique Parameters Page 1 1 Set the DBD bit to 0 2 Set the Page Code to 20h 3 Specify at least 12h for the Allocation Length byte 04h for the Parameter List Header 08h for the Block Descriptor 06h for the Vendor Unique Parameters Page 1 To return all possible MODE SENSE data 1 Set the DBD bit to 0 2 Set the Page Code to 3Fh 3 Specify at least 4Ch for the Allocation Length byte Restrictions for MODE SENSE Data in Page Format The following restrictions apply to the return of MODE SENSE parameters in page format m The value for the Allocation Length byte must be equal to or greater than the total number of bytes to be
62. and 0 are not 0 or the Vendor Unique fields bits 7 and 6 are other than valid Vendor Unique definitions for the specific command the command is terminated and Check Condition status 1s returned to the initiator The sense data is created as follows m The sense key is set to Illegal Request 5h m The Additional Sense Code is set to Invalid Field in CDB 24h m Additional Sense Code Qualifier 15 set to O 7 4 Command Status One status byte is sent from the EXB 8500 to the initiator at the completion of a command Status Byte Bit Byte T 6 5 4 3 2 1 0 00 Reserved Status Byte Code RSVD December 1991 7 7 7 8500 SCSI Command Set The meaning of the Status Byte Code bits 5 through 1 is shown in Table 7 2 Note that bit O 15 reserved so it is always O Table 7 2 Definition of the Status Byte Code Hex Bit Value Meaning 4 3 2 1 0 00h 0 0 0 0 0 Good Indicates that the EXB 8500 successfully completed the command Check Condition Indicates any error exception or 02h 0 0 0 1 O abnormal condition that causes sense information to be set Busy Indicates that the EXB 8500 is busy This 08h 0 1 0 0 O status is sent whenever the EXB 8500 is unable to accept a command from an initiator Reservation Conflict Indicates that the EXB 8500 is 18h 1 1 0 0 0 Es reserved for the exclusive use of another initiator
63. any EXB 8500 user who is responsible for m Installing and operating the EXB 8500 m Writing SCSI device drivers for the EXB 8500 Before reading this manual you should be familiar with the specifications for the EXB 8500 as described in the EXB 8500 8mm Cartridge Tape Subsystem Product Specification Part 2 of this manual assumes that you are familiar with basic SCSI terminology and concepts 1 3 Related Publications This manual provides instructions for installing operating and cleaning the EXB 8500 and for implementing the EXB 8500 s SCSI command set For additional information about the EXB 8500 refer to the following publications m EXB 8500 8mm Cartridge Tape Subsystem Product Specification 510200 m Monitor User s Guide for the 8mm Cartridge Tape Subsystem 510206 December 1991 1 5 1 General Information For information about the standards used for the EXB 8500 refer to the following publications ANSI Small Computer System Interface SCSI X3 131 1989 ANSI Small Computer System Interface 2 SCSI 2 X3T9 89 042 ANSI Helical Scan Digital Computer Tape Cartridge X3B5 89 136 Rev 6 Finally for information about other EXABYTE 8mm Cartridge Tape Subsystems refer to the following publications 8200 6mm Cartridge Tape Subsystem Product Specification 510005 8200 6mm Cartridge Tape Subsystem User s Manual 510006 82005 8mm Cartridge Tape Subsystem Product Specification and User s Manual 51
64. attaching EXB 8500 to mounting frame 2 7 cable requirements A 3 A 8 connecting EXB 8500 to power supply 2 12 connecting EXB 8500 to SCSI bus 2 10 equipment for 2 1 setting the SCSIID 2 3 tasks for 2 1 2 14 J jumpers for setting SCSIID 2 7 L LBOT defined 4 LEDs locationof 3 12 states indicated by 3 12 Index LEOT defined C 5 detected during write 28 5 detected during write filemarks 30 4 load procedure description 3 15 status returned during 3 15 6 42 time required for 3 16 LOAD UNLOAD 1Bh command effect of PREVENT ALLOW MEDIUM REMOVAL commandon 14 2 field descriptions for 10 1 10 4 LOCATE 2Bh command 11 1 11 6 exceptions and error conditions 11 4 using for directory support 1 B 10 logical beginning of tape See LBOT logical blocks 3 4 logical end of tape See LEOT Medium Error 3h sense key D 3 memory dump 19 5 24 3 Message In phase 6 22 6 33 Message Out phase 6 15 6 18 6 20 Message Parity Error 09h message 6 8 Message Reject 07h message 6 7 messages processing of 6 12 sequence of 6 10 supported by EXB 8500 6 4 microcode loading from SCSI bus 29 1 29 6 loading from tape 5 1 5 6 transferring to initiator 17 1 17 2 microcode update tape creating 5 4 using 5 1 MODE SELECT 15h command Block Descriptor 12 9 Block Length field 12 11 Buffered Mode field 12 7 Density Code field 12 9 Device Configuration Page page format Disconnect Reconnect Page page
65. be able to operate If this occurs use the CTS Monitor program to reload microcode from a BIN file through a serial cable attached to the Monitor port See the Monitor User s Guide for the mm Cartridge Tape Subsystem for complete instructions 5 2 510201 December 1991 5 Loading New Microcode from Tape 6 When the new microcode has been loaded successfully the EXB 8500 performs a full power on reset and self test The amber LED will be lit during the 30 second self test The load tape is ejected after approximately 15 seconds into the 30 second self test If the CTS Monitor program is running and the load was successful the following message will be displayed L Load of new code is successful If the load fails the amber LED will flash If the CTS Monitor program is running the following message will be displayed K Load of new code failed If a failure occurs retry the operation with another tape or use the CTS Monitor program to reload microcode from a BIN file through a serial cable attached to the Monitor port See the Monitor User s Guide for complete instructions Time Required to Load Code from Tape As shown in Table 5 1 approximately two minutes are required to load new microcode from a microcode update tape Table 5 1 Time Required to Load Code from Tape Step Time required seconds Load the microcode update tape 35 Read data from tape into buffer 7 Validate image in buffer 19 Unload ta
66. command in the reverse direction is received after a WRITE 0Ah or WRITE FILEMARKS 10h command any buffered data and filemarks are written to the tape before the locate operation is performed If an error occurs when the data in the buffer is being written the EXB 8500 returns Check Condition status and the space operation is not performed The initiator should issue a REQUEST SENSE 03h command to determine the cause of the error If the EXB 8500 has the EEPROM image for directory support and the EXB 8500 detects an EOD mark before the first filemark on tape it spaces over the EOD mark at high speed and up to 20 MBytes of erase area until it finds the filemark it is seeking For more information about directory support refer to Section 3 3 For a sample application showing how to use the EXB 8500 directory support feature refer to Appendix B 11 LOCATE 2Bh 11 1 Field Definitions Byte 01 Bit 2 BT Block Type The BT bit determines the type of block number contained in the Block Address field bytes 03 through 06 as follows 0 The Block Address field contains the SCSI logical block number numbered sequentially from the beginning of the tape The Block Address field contains an EXABYTE unique block address currently not implemented Byte 01 Bit 1 CP Change Partitions The EXB 8500 does not support multiple partitions A value other than 0 for this bit results in an error Byte 01 Bit 0
67. defined as follows Byte 00 Bit 7 BOP Beginning of Partition When this bit is set to 1 the tape is positioned at LBOT Byte 00 Bit 6 EOP End of Partition When this bit is set to 1 the tape is positioned between LEOT and PEOT Byte 00 Bit 2 BPU Block Position Unknown When this bit is set to 1 the block position is not known and cannot be obtained without tape motion The remainder of the data is not valid When this bit is set to 0 the remainder of the data is valid Byte 01 Partition Number The EXB 8500 does not support multiple partitions The value returned for this field is 0 510201 December 1991 18 READ POSITION 34h Bytes 04 through 07 First Block Location The First Block Location field indicates the block address associated with the current logical block position that is the block address of the next data block to be transferred between the initiator and the EXB 8500 if a READ or WRITE command is issued Note If you issue a READ POSITION command immediately after issuing a REWIND immediate command Immed bit set to 1 and you were writing data the position returned by the EXB 8500 may still reflect where the next write operation would have occurred not yet reset to 00 00 00 00 Bytes 08 through 11 Last Block Location The Last Block Location field is not valid for the EXB 8500 The value returned for this field is 0 Bytes 13 through 15 Number of Blocks in Buffer Numbe
68. depends on the operation A maximum of 12 seconds is required to empty the buffer to tape and to write an EOD mark EXB 8500 format tapes only A maximum of 180 seconds for a 112m tape is required to rewind a tape A maximum of 30 seconds is required to unload and eject a data cartridge Table 3 6 Summary of Unload Button Options Unload Button EXB 8500 Action Option peu Rewind to PBOT Unload and operation and write EOD eject tape Normal v v T Fast v b Super Fast ve If the EXB 8500 is performing a write operation when you press the fast version of the unload button the EXB 8500 will abort the command after it writes to tape the last logical block that was completely transmitted from the initiator However any partially transmitted logical blocks will be lost gt If media removal has been prevented with the PREVENT ALLOW MEDIUM REMOVAL command the tape will be unloaded but the data cartridge will not be ejected c The tape will be ejected whether or not media removal has been prevented with the PREVENT ALLOW MEDIUM REMOVAL command 3 20 510201 December 1991 3 Operating the EXB 8500 Status Reported for Unload Procedure If a command is issued to the EXB 8500 during the unload procedure the EXB 8500 returns Check Condition status with the sense key set to Unit Attention 6h Once the Unit Attention condition is reported all subsequent commands
69. from 0 to 160 KBytes See Chapter 12 for more information about the ND bit m When the Fixed bit is set to 1 the Transfer Length field contains the number of logical blocks to be read The block length is the length specified with the MODE SELECT command The allowable block sizes are defined by the READ BLOCK LIMITS 05h command The data is read from the next logical block on the EXB 8500 and transferred to the initiator Note When the value for the Transfer Length field is 0 no data is transferred and the current position of the EXB 8500 is not changed A value of 0 for these bytes is not an error Byte 05 Bits 7 and 6 Vendor Unique There are no vendor unique definitions for this command 15 3 15 READ 08h 15 2 Exceptions and Error Conditions The following exceptions and error conditions can occur with the READ command Filemark Detected If a filemark is detected before the transfer is finished the EXB 8500 returns Check Condition status The Filemark bit and the Valid bit are set in the extended sense data with the sense key set to No Sense When the READ command terminates the logical position is at the EOT side of the filemark encountered m If the Fixed bit is set to 0 the Information bytes are set to the requested transfer length m Ifthe Fixed bit is set to 1 the Information bytes are set to the difference between the requested transfer length and the actual number of blocks read EOD Detected
70. helpful to write fixed length blocks of 1 KByte or less in length when you are creating the pad areas B 2 510201 December 1991 Appendix B 8500 Directory Support Converting EXB 8200 Drivers EXB 8200 directory support drivers should work for EXB 8500 directory support with only a few modifications These modifications include the following Any filemarks in the directory must be removed Directories must be less than 20 MBytes More logical blocks must be used to create the pad areas than are actually used to write the master directory Note that this restriction does not apply if you use SPACE commands only Any references to the EXB 8200SX s SHOW BLOCK and FIND BLOCK commands should be changed to READ POSITION and LOCATE Writing Data for Directory Support To write data to make use of the EXB 8500 s directory support feature and the READ POSITION and LOCATE commands follow these steps 1 AtLBOT create a directory pad by writing filler data data that you do not intend to store to tape This reserves an area of tape for the master directory that will list the location of the data sets on tape LBOT DIRECTORY PAD The directory pad can be up to 20 MBytes in length It should be big enough to store the following The names of all of the data sets you plan to store on the tape plan for the maximum number of data sets and assume that each data set will use the longest allowabl
71. no vendor unique definitions for this command 510201 27 VERIFY 13h 27 2 Exceptions and Error Conditions The following exceptions and error conditions can occur with the VERIFY command Filemark Detected If a filemark is detected before the verify operation is completed the EXB 8500 returns Check Condition status The Filemark bit and the Valid bit are set in the extended sense data with the sense key set to No Sense When the VERIFY command terminates the logical position is on the EOT side of the filemark m Ifthe Fixed bit is set to 0 the Information bytes are set to the requested verification length m If the Fixed bit is set to 1 the Information bytes are set to the difference between the requested verification length and the actual number of blocks verified EOD Detected If EOD blank tape is detected during the verify operation the EXB 8500 returns Check Condition status The Valid bit is set in the extended sense data with the sense key set to Blank Check When the VERIFY command terminates the logical position is after the last recorded data block or filemark m Ifthe Fixed bit is set to 0 the Information bytes are set to the requested verification length m If the Fixed bit is set to 1 the Information bytes are set to the difference between the requested verification length and the actual number of blocks verified December 1991 27 3 27 VERIFY 13h PEOT Encountered If the physical end of t
72. not an error Table 12 1 Parameter List Lengths Non Page Format Specify this To transfer these parameters Parameter List Length No parameter list data 00h Parameter List Header only 04h Parameter List Header and 1 to 5 bytes of vendor unique parameters Pe DEN or Parameter List Header and Block Descriptor OCh Parameter List Header Block Descriptor and 1 to 5 bytes of vendor unique parameters ODh OEh OFh 10h or 11h 510201 12 MODE SELECT 15h Restrictions for MODE SELECT Data in Non Page Format The following restrictions apply to transfers of MODE SELECT parameters when the PF bit is 0 non page format m For data transfers greater than 0 bytes the entire 4 byte Parameter List Header must be transferred That is the entire 4 byte Parameter List Header must be transferred before the Block Descriptor or any vendor unique parameters can be transferred m Ifthe Block Descriptor is transferred it must be transferred in its entirety that is all 8 bytes partial transfers of this data segment are not allowed Note If the Block Descriptor is to be transferred set the Block Descriptor Length byte in the Parameter List Header to O8h Otherwise set this byte to 00h m Valid transfer lengths for the vendor unique parameters are 0 1 2 3 4 and 5 bytes transfers of the vendor unique parameters must start with byte 0 December 1991 12 3 1
73. of data that must be in the EXB 8500 s 1 MByte buffer before data in the buffer will be written to tape During a start stop read operation the minimum amount of free space that must be in the EXB 8500 s buffer before data will be transferred from the tape to the buffer The motion threshold is measured in 4 KByte increments See also reconnect threshold Millisecond Most significant bit Most significant byte Nanosecond National Safe Transit Association Physical beginning of tape Physical end of tape The state of the EXB 8500 when it is ready to process commands G 3 Glossary reconnect reconnect threshold Reserved RSVD SCSI SCSI ID signal assertion signal de assertion signal release status target um us or usec G 4 The function that occurs when the target arbitrates and reconnects to an initiator after a disconnect When a disconnect occurs during a streaming write operation the minimum amount of free space that must be in the EXB 8500 s 1 MByte buffer before the EXB 8500 reconnects to the initiator and data transfer from the initiator to the buffer continues When a disconnect occurs during a streaming read operation the minimum amount of data that must be in the EXB 8500 s buffer before the EXB 8500 reconnects to the initiator and data transfer from the buffer to the initiator continues The reconnect threshold is measured in 4 KByte increments See also motion t
74. operations after completion of the current READ command The early warning condition is reported as a Check Condition status with the sense key set to No Sense The EOM bit is set to 1 and the LBOT and PEOT bits are set to 0 in the extended sense data Byte 09 Gap Size The Gap Size field is not supported by the EXB 8500 The valid value for this field is 0 Byte 10 Bits 7 through 5 EOD Defined The EOD Defined field is not supported by the EXB 8500 The valid value for this field is 0 Byte 10 Bit 4 EEG Enable EOD Generation The EEG bit indicates that the EXB 8500 will generate an EOD mark The EEG bit is set to 1 in the MODE SENSE data and is ignored by the MODE SELECT command December 1991 12 27 12 MODE SELECT 15h Byte 10 Bit 3 SEW Synchronize at Early Warning The SEW bit indicates that the EXB 8500 will cause any buffered data to be written to the tape when the early warning condition LEOT is detected during a write operation This bit is set to 1 in the MODE SENSE data and is ignored by the MODE SELECT command Bytes 11 through 13 Buffer Size at Early Warning The Buffer Size at Early Warning field is not supported by the EXB 8500 The valid value for this field is 0 Byte 14 Select Data Compression Algorithm The Select Data Compression Algorithm is not supported by the EXB 8500 The valid value for this field is 0 12 28 510201 12 MODE SELECT 15h 12 9 Vendor Unique Parameters Page 1
75. other than READ for example INQUIRY REQUEST SENSE and MODE SENSE Parity Error in Data In Phase Information Commands If the initiator detects a parity error in data transferred from the EXB 8500 during a REQUEST SENSE MODE SENSE READ POSITION or INQUIRY command it should assert the Attention signal This causes the EXB 8500 to stop the data transfer The initiator should then send an Initiator Detected Error message to the EXB 8500 When it receives the Initiator Detected Error the EXB 8500 issues a Restore Pointers message and re sends the data 6 31 6 SCSI Physical Path Communications Initial Phase Data In Information Command Transition to Message Out for example INQUIRY REQUEST SENSE Does No initiator own current process Abort process Go Bus Free Message Reject No Operation Go Bus Free Execute warm reset Initiator Detected Error Set sense key to Aborted Command Bh Send Restore Data Pointers IN Go to Status phase Send Check Condition Go to Data In phase again Continue processing Send Message Reject IN Set sense key to Aborted Command Bh Go to Status phase Send Check Condition Figure 6 10 Message Processing during Data In Phase of Commands Other Than READ 6 32 510201 6 SCSI Physical Path Communications Message Processing In Status In Phase
76. owWwer o default in MODE Monitor B SELECT Determines whether the EXB 8500 8500 density writes data in EXB 8500 format or EXB 8500 format Density Code EXB 8200 format SCSI parity Enables or disables parity checking Parity checking PE checking on the SCSI bus enabled Disconnect on Enables or disables even byte Disconnect on j EBD even byte boundary disconnects any byte Disconnect in Indicates whether the EXB 8500 can Allow disconnect disconnect from the initiator during during data ND data data transfers transfers Cartridge type Defines what type of data cartridge P6 CT and P5 Default block size Determines whether the EXB 8500 writes fixed length or variable length logical blocks and indicates the default length for fixed length blocks 1 KByte 400h fixed length logical blocks Block Length December 1991 3 11 3 Operating the 8500 3 5 EXB 8500 Controls and Indicators 3 12 Figure 3 1 shows the location of the unload button and the green and amber LEDs on the front panel of the EXB 8500 DS N AMBER LED UNLOAD BUTTON Figure 3 1 EXB 8500 Front Panel Unload Button The unload button is the only operator control on the EXB 8500 It can be used to unload the tape from the EXB 8500 Depending on the EXB 8500 s EEPROM image the unload button can function in one of three ways m Asa
77. parity 0 Parity checking disabled Parity checking enabled The power on default value for PE is 1 Note For information about changing the power on default for parity checking refer to Section 3 4 Byte 00 Bit 0 NAL No Auto Load This bit is used to disable the automatic loading of the tape into the tape path when a data cartridge is inserted into the EXB 8500 0 Auto loading enabled Auto loading disabled The power on default value for NAL is 0 Byte 01 Bits 7 through 1 Reserved These bits are reserved 510201 12 MODE SELECT 15h Byte 01 Bit 0 P5 This bit is set to indicate that the data cartridge loaded in the EXB 8500 is expected to be a P5 European data cartridge When set to 1 this bit overrides the CT bit Note You can set the P5 bit only when the tape is positioned at LBOT Refer to Appendix C for information about data cartridge capacities and for an explanation of how the EXB 8500 autosizes data cartridges For information about changing the power on default for the cartridge type refer to Section 3 4 Byte 02 Motion Threshold The value in the Motion Threshold byte indicates the amount of data that must be in the buffer before tape motion is started for a buffered write or read operation The value is expressed in 4 KByte increments The default is 80h 512 KBytes Valid values range from 20h to DOh 128 to 832 KBytes When the buffer is filled to this point during a
78. space in 4 KByte increments that must be in the EXB 8500 s 1 MByte buffer before tape motion will start and data will be read from the tape to the buffer When the motion threshold value is exceeded tape motion starts The read from tape operation continues until the buffer is full and the tape motion stops Tape motion does not restart until the amount of free space in the buffer once again exceeds the motion threshold value Reconnect Threshold The reconnect threshold is used in streaming mode to control data transfers between the buffer and the initiator The reconnect threshold is measured in 4 KByte increments The default value for reconnect threshold is 80h 512 KBytes this value can be changed with a MODE SELECT command Streaming Write Operation In a streaming write operation the initiator to buffer transfer rate is equal to or greater than the buffer to tape transfer rate that is data transfers from the initiator occur at 500 KBytes per second or faster In this mode of operation the EXB 8500 disconnects from the initiator when the buffer becomes full but continues to write data to tape The reconnect threshold value represents the minimum amount of free space in 4 KByte increments that must be in the EXB 8500 s 1 MByte buffer before the EXB 8500 will reconnect to the initiator to accept additional data Note Because of hardware requirements only one quarter of the buffer is used during write operations in EXB 8200 fo
79. stays in effect with the initiator until renegotiated or until a reset condition SCSI bus reset Bus Device Reset message or power on reset occurs The agreement can also be terminated immediately after the negotiation if the initiator asserts the Attention signal and then sends either an Initiator Detected Error or a Message Reject message Note this abnormal termination of the synchronous transfer agreement happens more than eight times the EXB 8500 aborts synchronous transfer negotiations by going to the Bus Free phase Save Data Pointer 02h The EXB 8500 sends the Save Data Pointer message to direct the initiator to save a copy of the present active data pointer for the currently attached LUN Restore Pointers 03h The EXB 8500 sends the Restore Pointers message to direct the initiator to restore the most recently saved data pointers for the currently attached LUN to the active state Pointers to the Command Data and Status locations for the LUN are restored to the active pointers Command and Status pointers are restored at the beginning of the present command and status areas The data pointer is restored to the value at the beginning of the data area or the most recent Save Data Pointer value 510201 6 SCSI Physical Path Communications Disconnect 04h The EXB 8500 sends the Disconnect message to inform the initiator that the present physical path will be broken the EXB 8500 will disconnect by releasing the BSY signa
80. the command completed successfully While the tape is being re tensioned the initiator issues two more buffered WRITE commands to the EXB 8500 WRITE 7 and WRITE 8 The data associated with these commands is transferred to the EXB 8500 s buffer however none of the data in the buffer has been written to tape yet These commands also receive Good status After the tape is re tensioned the data associated with the first two WRITE commands WRITE 1 and WRITE 2 1s transferred from the buffer to tape As the EXB 8500 writes the data associated with WRITE 2 to tape it encounters LEOT As a result the next WRITE command WRITE 9 terminates abnormally and receives Check Condition status The extended sense data is set as follows Valid 1 Error Code 71h error associated with previous command EOM 1 Sense Key Oh No Sense Information bytes requested transfer length ASC and ASCQ 00h 00h This indicates that no error occurred but the initiator should note that PEOT is closer than would otherwise be expected See Important on the previous page LBOT 0 COUO D O 6 The remaining data in the buffer from WRITE 3 through WRITE 8 is written to tape Thus the tape is between 600 and 700 KBytes closer to PEOT than it would be if LEOT had been encountered during the current write operation WRITE Command Issued after LEOT Encountered Issuing a WRITE command after LEOT is encountered causes
81. the error recovery parameters used during read write operations This page is returned only when the Page Code field in the CDB is set to Byte 00 7 PS The Parameters Savable bit indicates if the MODE SENSE parameter data contained in this page is savable The EXB 8500 does not support this feature The value returned for this bit is 0 Byte 00 Bits 5 through 0 Page Code The Page Code identifies the type of MODE SENSE data being transferred This is the Read Write Error Recovery Page The value returned for the Page Code is Byte 01 Page Length The Page Length indicates the number of Read Write Error Recovery Page bytes that follow this byte The value returned for this byte is 07h Byte 02 Bit 5 TB Transfer Block The TB bit is not supported by the EXB 8500 The value returned for this bit is 0 December 1991 13 19 13 MODE SENSE 13 20 Byte 02 Bit 3 EER Enable Early Recovery The EER bit is not supported by the EXB 8500 The value returned for this bit is 0 Byte 02 Bit 2 PER Post Error The PER bit is not supported by the EXB 8500 The value returned for this bit is 0 Byte 02 Bit 1 DTE Disable Transfer on Error The DTE bit is not supported by the EXB 8500 The value returned for this bit is 0 Byte 02 Bit 0 DCR Disable Correction The DCR bit is not supported by the EXB 8500 The value returned for this bit is 0 Byte 03 Read Retry Count The Re
82. the examples in this section keep the following four rules in mind m The EXB 8500 allows only one format on any one tape m If you are writing data you must decide the tape s format at LBOT This is because the LBOT blocks define the format for the tape If you do not select a format the EXB 8500 writes in the power on default format Note To rewrite the tape in a different format you must overwrite the previously written LBOT pattern by issuing a WRITE 0Ah or WRITE FILEMARKS 10h command at LBOT m If you are appending to a previously written tape at a location other than LBOT the EXB 8500 automatically writes in the format of the data already on the tape m If you are reading a previously written tape the EXB 8500 automatically determines the tape s format for you However you can determine the format for yourself by following these steps 1 Load the data cartridge in the EXB 8500 2 Issue a MODE SENSE 1Ah command 3 Look at the Density Code in the Block Descriptor or RTF field in the Vendor Unique Parameters Page 1 Page Code 20h Writing and Reading in EXB 8200 Format This section describes how to use the EXB 8500 to write append to and read tapes in EXB 8200 format This format is compatible with the following EXABYTE products EXB 8200 EXB 8200SX EXB 8500 EXB 8500c EXB 8205 510201 12 MODE SELECT 15h Writing EXB 8200 Format Tapes To write tapes in EXB 8200 format follow these steps
83. the first EOD mark on the tape effectively disabling directory support for that command The values for the ADE bit are as follows 0 The EXB 8500 should ignore the first EOD mark as long as the EOD 15 located before the first filemark on the tape 1 The EXB 8500 should detect the first EOD mark on the tape and should stop when the first EOD is encountered If you are using a LOCATE command to locate information within the directory on a directory support tape set the ADE bit to 1 to prevent the EXB 8500 from crossing from the directory to the data area of the tape Similarly set this bit to 1 if you are using an EXB 8500 with the directory support feature to locate data on a tape that does not include a directory Note ADE bit is ignored if the EXB 8500 does not include the directory support feature Byte 09 Bit 6 Vendor Unique There is no vendor unique definition for this bit 11 3 11 LOCATE 2Bh 11 2 Exceptions and Error Conditions The following exceptions and error conditions can occur with the LOCATE command EOD Detected If the EOD mark is detected during the locate operation the EXB 8500 returns Check Condition status The Valid bit is set in the extended sense data with the sense key set to Blank Check 8h When the LOCATE command terminates the logical position is after the last recorded data block or filemark The Information bytes are set to the difference between the requested logical positi
84. the format of the data on the currently loaded data cartridge The WTF field on Page 20h indicates the format that will be used when the EXB 8500 writes data The values returned for these fields do not depend on the last operation performed by the EXB 8500 13 11 13 MODE SENSE Table 13 5 Effect of Various Actions on the Density Code Reported by MODE SENSE then the value reported for the Density Code is the actual format of the data on TPOWER format set with the most recent the tape s MODE SELECT format for writing tape If the most recent activity was a Power on v tape not loaded Load operation complete previously written tape MODE SELECT v command READ command v WRITE command v The Density Code reported in these cases reflects the format set by the most recent MODE SELECT command that set the Density Code to a non 7Fh value gt After the EXB 8500 loads a blank tape the Density Code reported by the MODE SENSE command will always indicate EXB 8500 format that is the Density Code will be set to either or 15h Note When the EXB 8500 appends new data to existing data it writes the new data in the same format as the data already on the tape In this case the writing format is automatically changed to the reading format no user intervention is required Once this automatic density chang
85. the returned data in the initiator s memory 4 Write the first data set to the tape 5 Issue another READ POSITION command to determine the starting location of the next data set Save the returned data in the initiator s memory 6 Write the next data set to tape 510201 3 Operating the EXB 8500 7 Repeat steps 5 and 6 until the tape is full or until you have no more data Note to write Rewind the tape and create a directory at the beginning of tape that lists the data set names along with the data returned for each READ POSITION command As shown in the application in Appendix B you may also want to create other directories throughout the tape that list the location of each file or block in the data set 3 4 EXB 8500 Configuration Options As described in the Monitor User s Guide for the 8mm Cartridge Tape Subsystem you can use the CTS Monitor program to change several of the EXB 8500 s normal power on defaults Once changed with Monitor the new settings for these configuration options become the power on defaults Note that because these configuration options correspond to fields in the MODE SELECT command see Table 3 4 MODE SELECT command issued after power on can override the settings of the configuration options Table 3 4 EXB 8500 Configuration Options Configuration Normal Equivalent field P5 P6 PI is expected to be loaded option set with What this option does
86. the tape is logically positioned on the EOT side of the filemark If a filemark is detected during a backward search the tape is logically positioned on the BOT side of the filemark In both cases the EXB 8500 returns Check Condition status The Valid and Filemark bits are set in the extended sense data with the sense key set to No Sense Oh The Information bytes are set to the difference between the requested number of blocks and the actual number of blocks spaced over Note If an unrecoverable media error is encountered during a space backward operation the value in the Information bytes may be a negative number 2s complement notation indicating how many blocks toward BOT were unreadable 25 3 25 SPACE 11h 25 4 EOD Blank Tape Detected If the Code field has a value of 000 space over n fixed or variable length blocks or 001 space over n filemarks and EOD blank tape is detected during a search the EXB 8500 returns Check Condition status The Valid bit is set in the extended sense data with the sense key set to Blank Check The Information bytes are set to the difference between the requested number of blocks or filemarks and the actual number of blocks or filemarks spaced over The tape is positioned so that a subsequent WRITE command can append data after the last block or filemark written before EOD blank tape Note Ifthe EXB 8500 s directory support feature is enabled you can issue a SPACE command with the A
87. to acquire tracking 21 7 21 REQUEST SENSE 03h 21 8 Byte 19 Bit 1 TNP Tape Not Present The EXB 8500 does not have a data cartridge inserted Byte 19 Bit 0 LBOT Logical Beginning of Tape If the cartridge is at logical beginning of tape this bit is set for any REQUEST SENSE command Byte 20 Bit 7 RSVD This bit is reserved Byte 20 Bit 6 TMD Tape Mark Detect Error An error occurred while attempting to perform a space filemark operation resulting in an invalid location relative to the requested location The valid bit is set to 1 and the Information bytes bytes 03 through 06 indicate the difference between the number of filemarks specified by the initiator and the actual number of filemarks processed by the EXB 8500 This may be a host recoverable error The initiator needs to re send the SPACE command with the correct number of filemarks This bit is valid for tapes written in EXB 8200 format only Byte 20 Bits 5 WP Write Protect If the data cartridge is write protected this bit is set for any REQUEST SENSE command Byte 20 Bit 4 FMKE Filemark Error A write error occurred when the EXB 8500 was attempting to write a filemark Byte 20 Bit 3 URE Under Run Error Hardware data formatter underrun error Byte 20 bit O also set to 1 Byte 20 Bit 2 WE1 Write Error 1 Maximum number of rewrites attempted Media error Byte 20 Bit 1 SSE Servo System Error Catastrophic hardware error
88. to the tape December 1991 B 1 Appendix B 8500 Directory Support m DS 1 through DS n are data sets containing groups of data files m DIR 1 through DIR z are directories for data sets DS 1 through DS n These directories contain data from READ POSITION commands that points to the locations of the individual files within each data set m EOD2isthe second end of data mark on the tape This EOD is automatically written after the last data set directory when you rewind the tape Sample Application for Directory Support The step by step description that follows explains how to create this data structure and access the data using the READ POSITION and LOCATE commands Restrictions on Similar Applications The sample application in this appendix demonstrates only a suggested implementation of directory support You may choose to implement directory support in any manner that fits your needs with the following restrictions m Do not include filemarks in the master directory The first filemark on the tape must be the one written at the end of the pad created after the space for the master directory m The master directory must be 20 MBytes or less in length m Toensure that no two logical blocks on a directory support tape have the same logical block address the number of logical blocks records in the master directory must be less than the number of logical blocks used to create the pad areas For this reason you may find it
89. written before the erase operation is performed EXB 8200 Format Tapes For a tape written in EXB 8200 format a legal position for an erase operation is the tape positioned at any one of the following locations m LBOT m End of data blank tape m BOT side of a long filemark 8 3 Exceptions and Error Conditions The following exceptions and error conditions can occur with the ERASE command Illegal Request The EXB 8500 returns Check Condition status with the sense key set to Illegal Request 5h if the ERASE command is issued from an illegal position December 1991 8 3 8 ERASE 19h Notes 8 4 510201 9 INQUIRY 12h Bit 7 6 5 4 3 2 1 0 Byte 00 0 0 0 1 0 0 1 0 01 Logical Unit Number Reserved EVPD 02 Page Code 03 Reserved 04 Allocation Length 05 Vendor Unique Reserved 0 0 The INQUIRY command requests that information about EXB 8500 parameters be sent to the initiator The INQUIRY command is executed whether a tape is loaded and whether the EXB 8500 has been reserved by another initiator Response to the INQUIRY command is not ignored or rejected during the power on self test Responding to the INQUIRY command does not cause a pending Unit Attention to be cleared for that initiator 9 1 Field Definitions December 1991 Byte 01 Bit 0 The Enable Vital Product Data bit indicates the type of inquiry data being requested by the ini
90. 0 311EDh 188F68h 12E7h 9738h P6 120 P5 90 45F84h 22FC20h 119Dh 8CE8h Track and block counts from LEOT to PEOT are approximate As described in this section the EXB 8500 can accurately determine the lengths of these tape sizes at December 1991 C 7 Appendix C Data Cartridge Capacities EXATAPE Capacities Table C 5 compares EXATAPE data cartridges with industry standard cartridge sizes and lists the approximate capacities of these data cartridges in EXB 8500 format and in EXB 8200 format EXATAPE data cartridges are available from EXABYTE in the following three sizes m EXATAPE 15m approximately 608 MBytes of EXB 8500 formatted data capacity to the physical end of tape m EXATAPE 54m approximately 2 421 MBytes of EXB 8500 formatted data capacity to PEOT m EXATAPE 112m approximately 5 016 MBytes of EXB 8500 formatted data capacity to PEOT Table C 5 Approximate Capacities of EXATAPE Data Cartridges Size of Equivalent 7 Approximate Capacity to LEOT EXATAPE Cartridge Old Identifier Size EXB 8500 format EXB 8200 format 15m P6 15 256 588 MBytes 294 MBytes P6 30 512 1 175 MBytes 588 MBytes 54m P6 60 1024 2 348 MBytes 1 174 MBytes P6 90 1536 3 522 MBytes 1 761 MBytes P6 120 2048 4 695 MBytes 2 348 MBytes 112m P5 90 4 944 MBytes 2 472 MBytes The column labeled EXATAPE lists the current data cartridges available for purchase from EXABYTE These data cartridges are recommended for use with all EXABYTE p
91. 00 Command Set 4 4 44 24 baw ee De 9x 9X Table 7 2 Definition of the Status Byte Code LOAD UNLOAD 1Bh Table 10 1 Action Occurring Based on Load Bit and Data Cartridge Status MODE SELECT 15h Table 12 1 Parameter List Lengths Non Page Format Table 12 2 Parameter List Lengths Page Format Table 12 3 Values to Designate for Parameter List Length Page Format Table 12 4 Values for Density Code Field in MODE SELECT Command xvi 10 3 510201 MODE SENSE 1Ah Table 13 1 Values for Page Code Field in the MODE SENSE Command 13 3 Table 13 2 Allocation Lengths Non Page Format 13 4 Table 13 3 Allocation Lengths Page Format 13 6 Table 13 4 Values Returned for Medium Type Byte in MODE SENSE Data 13 9 Table 13 5 Effect of Various Actions on the Density Code Reported by MODE SENSE 45404 246 Me wade Ee ee eG 13 12 Table 13 6 Values for the Density Code Byte in MODE SENSE Command 13 13 RECEIVE DIAGNOSTIC RESULTS 1Ch Table 19 1 Page Codes for RECEIVE DIAGNOSTIC RESULTS Command 19 3 Table 19 2 Page Lengths for RECEIVE DIAGNOSTIC RESULTS Command 19 4 Table 19 3 Location of Memory Dump Information 19 5 Table 19 4 Bytes Returned in a Trace Dump 19 6 REQUEST SENSE 03h Table 21 1 Sense Key Values 5o y RR RE es 21 4 SEND DIAGNOSTIC 1Dh Tab
92. 0011 8205 6mm Cartridge Tape Subsystem Product Overview 510700 8500 8mm Cartridge Tape Subsystem Product Specification and User s Manual 510207 1 4 Safety and Regulatory Agency Standards Safety Standards When purchased from EXABYTE Corporation the EXB 8500 is certified as a component by the following domestic and international product safety standards UL Standard 1950 1st Edition Information Technology Equipment UL Standard 478 4th Edition Electronic Data Processing Units and Systems CSA Standard C22 2 No 220 M1986 Information Processing and Business Equipment CAN CSA Standard C22 2 No 950 89 Safety of Information Technology Equipment pending IEC 950 EN60950 Safety of Information Technology Equipment including Electrical Business Equipment TUV 510201 December 1991 1 General Information Electromagnetic Compatibility EMC Standards When properly installed with shielded cables and adequate grounding of the SCSI bus and the input power the EXB 8500 meets the requirements for radiated and conducted emissions as defined by the following standards m FCC Rules Part 15 Class B Computing Devices m Canadian Department of Communications Radio Interference Regulation Digital Apparatus Class B m VDE Vfg 1046 1984 Class B m CISPR Publication 22 1985 Class A Electromagnetic Interference EMI Standards When properly installed with shielded cables and adequate grounding of the
93. 05 Bit 7 CLRCNT The CLRCNT bit enables the initiator to reset the Read Write Data Error counter the Tracking Retry counter the Read Write Retry counter and the Underrun Overrun counter Values for the CLRCNT bit are as follows 0 Do not reset counters Reset counters If the CLRCNT bit is set to 1 the counters are reset when the REQUEST SENSE command completes The initiator must allocate 29 1Dh bytes for sense data to be read in order to reset the counters Byte 05 Bit 6 VU Vendor Unique There is no vendor unique definition for this bit 21 REQUEST SENSE 03h 21 2 Extended Sense Bytes Bit 7 6 5 4 3 2 1 0 Byte 00 Valid Error Code 01 Segment Number 02 FMK EOM ILI RSVD Sense Key 03 MSB Information 06 LSB 07 Additional Sense Length Se Reserved 09 10 Reserved 11 Underrun Overrun Counter 12 Additional Sense Code 13 Additional Sense Code Qualifier ps Reserved 15 16 MSB 17 Read Write Data Error Counter 18 LSB 19 TNP LBOT 20 RSVD TMD WP FMKE URE WEI SOE FE 2 RSVD RSVD RRR CLND CLN PEOT WSEB WSEO 22 Reserved 23 MSB 24 Remaining Tape 25 LSB 26 Tracking Retry Counter 27 Read Write Retry Counter 28 Fault Symptom Code 21 2 510201 21 REQUEST SENSE 03h The EXB 8500 supports the standard exten
94. 1 Load a blank data cartridge in the EXB 8500 or load a previously written data cartridge that you want to overwrite 2 Issue MODE SELECT command at LBOT Set the Density Code in the Block Descriptor to 14h Note Refer to page 12 40 if you cannot issue MODE SELECT commands 3 Issue WRITE or WRITE FILEMARKS command to write the data Appending to EXB 8200 Format Tapes If a tape has already been written in EXB 8200 format and you want to write additional data on the tape follow these steps 1 Load the data cartridge in the EXB 8500 Note If you issue a MODE SELECT command at LBOT be sure that the Density Code in the Block Descriptor is set to 14h 2 Issue a READ 08h or SPACE 11h command to move away from LBOT and to a legal position for appending Note Legal positions for appending in EXB 8200 format are the beginning of tape side of a long filemark and at the end of data blank tape 3 Issue a WRITE or WRITE FILEMARKS command to write the additional data The EXB 8500 automatically sets the Density Code to EXB 8200 format Note The WTF bit in the MODE SENSE command indicates that the EXB 8500 is writing in EXB 8200 format 001b December 1991 12 37 12 MODE SELECT 15h 12 38 Reading EXB 8200 Format Tapes To use the EXB 8500 to read an EXB 8200 format tape follow these steps 1 Load the data cartridge in the EXB 8500 2 Issue a READ command to read the data The EXB 8500 automatically deter
95. 100 Power on Tests without Tape 24 4 Test 101 Power on Write Read and Load Tests without Tape 24 5 Test 110 Power on Tests with Tape 2 2299 Rx x S 24 6 Test 111 Power on Write Read and Load Tests with Tape 24 6 510201 25 SPACE 11h eee 25 1 23 1 Field Definitions 5 3 9437 9 X CO 99308 25 2 25 2 Exceptions and Error Conditions lt a uice s woes s Oe E 25 3 Filemark Detected os 839 0 3 845254 GH 25 3 EOD Blank Tape Detected 2 5 44 ok Ron RR E REY 25 4 PBOT Encountered e sose sa sra EY oe See xS 25 4 PHOT Encou ter d as 4 0 ses que wR INO ADR CON EX 25 4 Unrecoverable Error ook obo dor o 820894 296225 94 25 5 BIER Ue xw EON EROR oe Oe UE RU 3 3 e 25 5 25 9 Pde 4x uos ow desc mde Aca Bred Ere ded 25 5 26 TEST UNIT READY 00h 42 oom mmm Rem chm ROI x 26 1 26 1 Field Definitions lt sop woe vc oko SS Sle Be he Gare Xe EE 26 1 20 VERIFY T9B oa dione aca a o9 ew im D 27 1 27 10 Field Definitions 54 sop wu x 3X 309 3 3 OY EROS Xy Xo Boa ws 27 1 27 2 Exceptions and Error Conditions 22 4 6 3 ed ok eee eeu ence 27 3 Pilemark Detected eg oo ae RUBER Oe wu xc Ee 27 3 EOD Detected 3124 9 Gd ee ne See Pere ER Eee SG 27 3 PROV E countered
96. 2 9 MODE SENSE command 13 11 Block Length field MODE SELECT command 12 11 blocks logical 3 4 physical 3 4 C 4 Buffered Mode field 12 7 buffered write operation 28 4 Bus Device Reset 0Ch message described 6 8 effect of 6 41 Busystatus 7 9 December 1991 C cable requirements cartridges See data cartridges chassis grounding 2 12 Check Condition status 7 9 cleaning the EXB 8500 frequency of 4 1 instructions for 4 2 Command Complete 00h message described 6 4 processing 6 33 Command Out phase 6 17 commands ERASE 19h 8 1 8 4 formaterrors in 7 6 general field definitions for 7 4 general format of 7 2 INQUIRY 12h 9 1 9 8 LOAD UNLOAD 10 1 10 4 LOCATE QBh 11 1 11 6 MODE SELECT 15h 12 1 12 40 MODE SENSE 1Ah 13 1 13 34 PREVENT ALLOW MEDIUM REMOVAL 14 1 14 2 A 3 A 8 READ 08h 15 1 15 8 READ BLOCK LIMITS 05h 16 1 16 2 READ BUFFER 3Bh 17 1 17 2 READ POSITION 34h 18 1 18 4 RECEIVE DIAGNOSTIC RESULTS 1Ch 19 1 19 8 RELEASE UNIT 17h 20 1 20 2 REQUEST SENSE 03h 21 1 21 12 RESERVE UNIT 16h 22 1 22 2 REWIND 01h 23 1 23 2 SEND DIAGNOSTIC 1Dh 24 1 24 8 SPACE 11h 25 1 25 6 status byte returned at completion of 7 7 TEST UNIT READY 00h 26 1 26 2 VERIFY 13h 27 1 27 6 WRITE 0Ah 28 1 28 10 WRITE BUFFER 3Bh 29 1 29 6 WRITE FILEMARKS 10h 30 1 30 6 compatibility of EXB 8500 3 2 configuration option
97. 2 MODE SELECT 15h 12 4 Byte 04 Parameter List Length Page Format The Parameter List Length byte indicates the length of the parameter list that will be transferred from the initiator to the EXB 8500 during the Data Out phase When the PF bit is set to 1 page format all parameters after the Block Descriptor are transferred as pages of related parameters The value of the Parameter List Length byte depends on which combination of parameter pages is being transferred The value for this byte must represent the total number of bytes to be transferred from the initiator to the EXB 8500 Table 12 2 shows the number of bytes that should be designated to transfer the various types of MODE SELECT parameter segments When the value for the Parameter List Length byte 15 0 no data is transferred from the initiator A value of 0 for this byte is not an error Table 12 2 Parameter List Lengths Page Format To transfer these Designate this amount parameters No parameter list data 0 bytes Oh Parameter List Header 4 bytes 4h Block Descriptor 8 bytes 8h Read Write Error Recovery Page Code 01h 9 bytes 09h Disconnect Reconnect Page Page Code 02h 12 bytes OCh Data Compression Page Page Code 0Fh 16 bytes 10h Device Configuration Page Page Code 10h 15 bytes OFh Vendor Unique Parameters Page 1 Page Code 20h 6 bytes 06h Vendor Unique Parameters Page 2 Pa
98. 200 format 3 3 end of data mark 3 6 filemarks 3 5 logical block structure 3 4 physical block structure 3 4 reading 12 39 search fields in 3 5 track structure 3 3 writing 12 38 EXB 8500c compatibility with EXB 8500 32 extended message described 6 5 processing 6 20 6 22 extended sense bytes 21 2 F fast unload option 3 18 Fault Symptom Codes error recovery procedures for 7 listof E 1 E 8 REQUEST SENSE command 21 10 use of for MODE SELECT command 12 35 filemarks detected during read 15 4 detected during space 25 3 detected during verify 27 3 in EXB 8500 and EXB 8200 formats 3 5 writing with WRITE FILEMARKS command 30 1 firmware updates loading from SCSI bus 29 1 29 6 loading from tape 5 1 5 6 transferring code to initiator 17 1 17 2 fixed length logical blocks 12 11 format errors in CDBs 7 6 December 1991 Index G gap threshold setting with MODE SELECT non page format 12 16 setting with MODE SELECT page format 12 25 12 33 Good status 7 8 grounding the EXB 8500 2 12 H Hardware Error 4h sense key D 4 high speed search 3 5 Identify message 6 9 Illegal Request 5h sense key ASC and 5 values for D 5 LOCATE command 11 5 READ command 15 7 SPACE command 25 5 VERIFY command 27 6 WRITE command 28 10 Initiator Detected Error 05h message 6 7 INQUIRY 12h command field descriptions for 9 1 Standard Inquiry Data 9 3 Unit Serial Number Page 9 8 Vital Product Data Page 9 7 installation
99. 3 Appendix C Data Cartridge Capacities Track and Physical Block Counts Table C 3 and Table C 4 list the following information for tapes written in EXB 8500 format and EXB 8200 format m The number of tracks and 1 024 byte physical blocks between LBOT and LEOT m The approximate number of tracks and 1 024 byte physical blocks between LEOT and PEOT Note that the number of tracks and physical blocks between LBOT and LEOT and between LEOT and PEOT depends on the data cartridge type and size as well as on whether the tape is written in EXB 8500 format or EXB 8200 format The track and physical block counts are based on the definitions of the following Physical beginning of tape PBOT Logical beginning of tape LBOT Logical end of tape LEOT Physical end of tape PEOT Physical Beginning of Tape PBOT The physical beginning of tape PBOT is located at the point on the tape where the translucent leader material is attached to the media This position is detected by an optical sensor in the tape transport mechanism Logical Beginning of Tape LBOT The logical beginning of tape LBOT is automatically recorded on the tape by a write operation that is issued at the beginning of tape LBOT is recorded 735 10 mm 28 9 0 39 inches from PBOT LBOT consists of a series of tracks that are used to indicate LBOT s location and to calibrate the servo system The first track containing data blocks is recorded directly after the
100. 4 exu 4444 ba 48 Ok E RI WORT 7 3 Typical Format of the Control Byte 7 3 7 2 Field Definitions for the Command Descriptor Block 7 4 Field Definitions for Six Byte 5 7 4 Field Definitions for Ten Byte CDBs v woo Roh ORE CR 7 5 7 3 Command Format Errors ssa x 244044 ale ws x 7 6 Ilegal Operation Code 6 0 quz ce od Oe 6 ae we Rog Oe A 7 6 Ilegal Logical Unit Number aoe a8 7 6 Reserved Byte or Bits Non Zero xo wok OX Y OY OR RR 7 7 Control Byte or Bits Set Incorrectly 24 8 2 dex e ER s 7 7 7A Command Stat s lt s ces o 9o R9 xx Y betta Paw shes Ra 7 1 DUBS BYE uris qeu 90 958 39 iot VU ROS E WE OU 7 7 Status Byte Explanations uo gs 224 004 Ge ae Sea 99 eee eS 7 8 B ERASE 19D i sabi ete HUE oe SO ew 8 1 8 1 Field DefnmoBs xo x x33 ee Gee Ge BLE a BES 8 2 pe Tape Positioning s soe poso Se ee Rew ee oe Be 8 3 8 3 Exceptions and Error Conditions 2 2252 808 8s o tk 8 3 Illegal Reg st x ours oix SOS De ee Ree Ose qs 8 3 9 INQUIRY 12h i sz a RR OR mmo e m n 9 1 9 1 Field Definitions scs aragon Xue done veces 9 1 Returning Inquiry Data uro yc de y xo poko ee 9 2 9 2 Standard Inqui
101. 415 69 moo x x See Um EO d 1 3 1 2 About This Manual 44 23 x fea Saa EE 1 4 Intended Audience nuns xou Ped sad oe X SO OR 1 5 1 3 Related Publications e ele sce tid ee eek 3 1 5 1 4 Safety and Regulatory Agency Standards 1 6 2 Installing the EXB 8500 oo 2 1 2 1 Required and Optional Equipment 2 1 2 2 Unpacking the EXB 8500 s aats bs ee RR Pr SDs 2 2 2 9 etme the SCSLID acu uie E eq CRAS REC CR KC cde 2 3 Setting the SCSI ID with the DIP Switches 2 4 Setting the SCSI ID witha Remote Switch 2 5 Setting the SCSI ID with Jumpers 2 222222 Rok RR 2 7 2 4 Attaching the EXB 8500 toa d Ee 2 7 2 5 Connecting the 8500 to the SCSI Bus 2 10 Single Ended SCSI Configuration 4 2 v ax 3 3o 2 10 Differential SCSI Configuration r3 2 11 Connecting the SCSI Cable e 2 11 2 6 Connecting the EXB 8500 to the Power Supply 2 12 2 7 Performing the Initial Power On 2 5 2299 d 2 13 3 Operating the EXB 8500 3 1 3 1 Read Write Compatibility eee S56 eo 3 2
102. 6 7 Message Processing during the Data Out Phase of a WRITE Command 6 25 Figure 6 8 Message Processing during the Data Out Phase of MODE SELECT Command Gee Sg meu PES 6 27 Figure 6 9 Message Processing during the Data In Phase of aREAD Command 6 29 Figure 6 10 Message Processing during Data In Phase of Commands Other Than READ 2422x433 992X4X8 4925499939 6 31 Figure 6 11 Message Processing during the Status In Phase 6 32 Figure 6 12 Message Processing during Command Complete Message In Phase 6 33 Figure 6 13 Message Processing after EXB 8500 Reselects Initiator with Identify Message ue oup Pod x HY we GLE Sw X Ss 6 35 Figure 6 14 Message Processing while EXB 8500 Is Executing Disconnect SEQUENCE 24444445 3h der cox O48 Y EEG 6 37 December 1991 xix RECEIVE DIAGNOSTIC RESULTS 1Ch Figure 19 1 Example SCSI Instruction Trace Table EXB 8500 Directory Support Figure B 1 Typical Arrangement of Information on a Directory Support Tape B 1 XX 510201 Part 1 Installing and Operating the EXB 8500 1 General Information This manual provides instructions for installing and using the EXABYTE EXB 8500 8mm Cartridge Tape Subsystem EXB 8500 It also provides reference information for developing software to support EXB 8500 applications 1 1 About the EXB 8500 The EXB 8500 is a high performance high capacity 8mm cartridge tape subsystem designed
103. 7 LSB 08 MSB i Decompression Algorithm 11 LSB 12 Reserved 15 December 1991 Field Definitions The Data Compression Page specifies parameters for the control of data compression Important The EXB 8500 does not support data compression This page is included to enable EXB 8500 drivers to be upwardly compatible with products supporting data compression such as the EXB 8500c This page is returned when the Page Code in the CDB is set to OFh Byte 00 Bit 7 PS Parameters Savable The Parameters Savable bit indicates if the MODE SENSE parameter data contained in this page is savable The EXB 8500 does not support this feature The value returned for this bit is 0 13 23 13 MODE SENSE 13 24 Byte 00 Bit 6 Reserved This bit is reserved Byte 00 Bits 5 through 0 Page Code The Page Code identifies the type of MODE SENSE data being transferred This is the Data Compression Page The value returned for this field is OFh Byte 01 Page Length The Page Length indicates the number of Data Compression Page bytes that follow this byte The value returned for this byte is OEh Byte 02 Bit 7 DCE Data Compression Enable The EXB 8500 does not support data compression so the value returned for the Data Compression Enable bit is 0 Byte 02 Bit 6 DCC Data Compression Capable The Data Compression Capable bit indicates whether the device supports data compression The
104. 8500 off and back on again power on reset Sending an RST pulse on the SCSI bus for a minimum of 25 usec SCSI bus or hard reset A SCSI bus reset immediately clears all devices from the bus resets their associated equipment and terminates all pending I O processes Issuing a Bus Device Reset 0Ch message to the EXB 8500 device or warm reset A device reset clears the EXB 8500 from the bus causes all commands sent to it to be cleared and terminates all pending I O processes Note Ifa SCSI bus or device reset occurs during a power on reset the power on reset will be restarted Effect of Power on Reset Performing a power on reset causes the EXB 8500 to complete its power on self test as indicated by the LEDs both on In addition a power on reset has the following effects If the EXB 8500 is connected to the SCSI bus the SCSI bus goes to the Bus Free phase A cyclic redundancy check CRC of the control code is performed The servo is reset and a servo self test is performed EXB 8500 parameters are reset to their default states A test of the microprocessor s external memory is performed A buffer memory test is performed After a power on reset the EXB 8500 will respond on the SCSI bus within 3 seconds December 1991 6 41 6 SCSI Physical Path Communications 6 42 Effect of SCSI Bus and Device Resets SCSI bus and device resets have the following effects m Ifthe EXB 8500 is connected t
105. 8500 on but do not insert a data cartridge Issue a TEST UNIT READY 00h command The EXB 8500 must return Check Condition status Then issue a REQUEST SENSE command The sense key should be set to Not Ready no data cartridge present 24 4 510201 24 SEND DIAGNOSTIC 1 Test 101 Power on Write Read and Load Tests without Tape During this test the EXB 8500 first performs its power on RAM and servo diagnostic tests If no failures are found the amber LED on the front panel flashes to prompt you to insert a write enabled scratch data cartridge The EXB 8500 then loads the tape and performs the following operations Writes internally generated data to the buffer Writes buffered data to the tape Rewinds the tape Reads data from the tape to the buffer Reads and verifies the data in the buffer Rewinds the tape If these operations complete successfully the EXB 8500 returns Good status and unloads and ejects the data cartridge If the PREVENT MEDIUM REMOVAL command has been issued it is overridden Improper test setup causes the EXB 8500 to return Check Condition status with the sense key set to Illegal Request The EXB 8500 disconnects during this test Note Test 101 cancels all synchronous negotiations and erases the trace tables In addition the unload button is disabled during this test Setup for Test 101 Before starting this test power the EXB 8500 on but do not insert a data cartridge Issue a TEST U
106. 91 6 13 6 SCSI Physical Path Communications Initial Phase Selection Transition to Message Out Go Bus Free Go Bus Free Go Bus Free Execute warm reset Identify Is Disconnect bit Set Disallow disconnects Allow disconnects Yes Is LUN valid equal 0 Set invalid LUN flag Clear invalid LUN flag Is Attention high Stay in Message Out phase Go to CDB In phase Figure 6 1 Message Processing after the Selection Phase 6 14 510201 December 1991 6 SCSI Physical Path Communications Message Processing in the Message Out Phase Figure 6 2 shows the message sequences for Message Out bytes received during a previously initiated Message Out phase Note that Message Reject and Initiator Detected Error messages received after a previous Message Out phase are treated as catastrophic errors committed by the initiator Parity Error in the Message Out Phase When parity checking is enabled and the EXB 8500 detects a parity error in a message received from the initiator the EXB 8500 requests that the initiator reissue the message by going to the Message Out phase again If a parity error occurs during the first message sequence Identify message followed by contiguous Message Out bytes the entire sequence must be retransmitted that is the initiator should reissue the Identify message and all following bytes If a parity error is
107. A for a description of the cable requirements For single ended SCSI configurations ensure that the total length of the cable does not exceed 6 meters 19 68 feet For differential SCSI configurations ensure that the total length of the cable does not exceed 25 meters 82 feet External SCSI bus terminator differential SCSI configuration only If you are installing the differential SCSI configuration of the EXB 8500 and the EXB 8500 will terminate the SCSI bus you must provide external termination To ensure that the EXB 8500 performs to specification EXABYTE recommends a Methode Electronics Inc dataMate DM103 01 0 differential external terminator Note If necessary you can terminate the single ended EXB 8500 externally In this case remove the resistor terminators from the back of the EXB 8500 and install an external terminator To ensure that the EXB 8500 performs to specification EXABYTE recommends a Methode Electronics Inc dataMate DM103 02 0 single ended external terminator 2 1 2 Installing the EXB 8500 m Power cable See Appendix A for a description of the cable requirements m Standard DC supply voltages 5 volts and 12 volts The following equipment is optional Remote switch or jumpers if you want to set the SCSI ID remotely The initiator must use a female Molex 22 55 2061 or equivalent cable connector to control the address remotely Mounting frame or brackets if desired Four 86 32 screw
108. AGNOSTIC RESULTS 1 Page Code 94h Memory Dump Information Bytes 04 through nn up to 36 960 bytes Memory Dump Informa tion These bytes contain memory dump information as shown in Table 19 3 Table 19 3 Location of Memory Dump Information Bytes Contain this data 0 to FFh Processor on chip data 100h to 7FFFh External RAM data 8000h to 97FFh LSI hardware registers Receiving a Memory Dump This section describes the steps and bit settings for receiving complete and partial memory dumps Complete Memory Dump Monitor Dump To receive a complete memory dump Monitor dump follow these steps 1 Issue a SEND DIAGNOSTIC command with the SelfTest DevOfL and UnitOfL bits set to 000 the Parameter List Length set to 0000 and the MD bit set to 1 2 Issue a RECEIVE DIAGNOSTIC RESULTS command with the Allocation Length field set to 9064h and the TD bit set to 0 Partial Memory Dump To receive a partial memory dump follow these steps 1 Issue a SEND DIAGNOSTIC command with the SelfTest DevOfL and UnitOfL bits set to 000 and the MD bit set to 1 Indicate the desired starting address in the Parameter List Length field 0000 to 97FFh 2 Issue a RECEIVE DIAGNOSTIC RESULTS command with the Allocation Length field set to the desired number of bytes less than 9064h and the TD bit set to O Note Nonexistent registers or uninitialized bytes will be returned as FFh December 1991 19 5 19 RECEIVE DIAGNOSTIC R
109. B 12 Buffer Size at Early Warning 13 LSB 14 Select Data Compression Algorithm December 1991 Field Definitions The Device Configuration Page specifies configuration parameters for the EXB 8500 This page is returned only when the Page Code in the CDB set to 10h Byte 00 Bits 5 through 0 Page Code The Page Code identifies the type of MODE SENSE data being transferred This is the Device Configuration Page The value returned for the Page Code is 10h Byte 01 Page Length The Page Length indicates the number of Device Configuration Page bytes that follow this byte The value returned for this byte is ODh Byte 02 Bit 6 CAP Change Active Partition The CAP bit is not supported by the EXB 8500 The value returned for this bit is 0 13 25 13 MODE SENSE Byte 02 Bit 5 CAF Change Active Format The value returned for CAF bit is 0 Byte 02 Bits 4 through 0 Active Format The Active Format field contains data that modify the media format parameters The definition for the active format field is 4 3 2 1 0 Reserved Gap Threshold Byte 02 Bits 4 and 3 Reserved These bits are reserved Byte 02 Bits 2 through 0 Gap Threshold The Gap Threshold byte specifies the maximum number of consecutive gap blocks that the EXB 8500 will write on the current track while determining whether an empty buffer exists during a write operation After wr
110. BO aE 15 2 15 2 Exceptions and Error Conditions uides ok 15 4 Filematk Deipeted s 222929493 S46 Roe be GSE Ga 15 4 POD Detected A a X B ew re 15 4 PBOT Encountered quu uo Gow Bae eee Se GS Saw rox e dog ed 15 5 Unrecoverable Error ou eee MS ee Sox qux do ee we ae 15 5 Transfer Length Incorrect 229 x eek 44688855 24454 15 6 mor Ear Mise e RO PRU aC ee Oe ee 15 7 16 READ BLOCK LIMITS 05 16 1 Field Definitions Ree he ea EOS Un 3 16 1 16 2 Read Block Limits Data 4 xo 3E Some Soe 94 16 2 17 READ BUFFER 3CH 45 sacra n 17 1 17 1 Field Definitions ss o eue eG Sees Ge ag oa daw 17 1 17 2 Exceptions and Error Conditions 4442644 84 17 2 Hardware or SCSI Bus Error 24 2454 4 244844 X RR EX 17 2 Allocation Length Incorrect 2444 493 3 o EOS s ease ae 17 2 December 1991 xi 18 19 20 21 22 23 24 xii READ POSITION 34h RR Rm 18 1 Field DelihiltioHs E Se Se 43 94 3 2 X CRUS 18 1 18 2 edd Postion Data s s s s ses quce ow inq eh P we ed RS 18 2 RECEIVE DIAGNOSTIC RESULTS 19 1 Field D finitions ss iue 383 ae ee RE x go 19 2 19 2 Returning SEND DIAGNOSTIC Data
111. Bytes 01 through 03 Maximum Block Length The value returned for the Maximum Block Length field is 03C000h 240 KBytes If the ND No Disconnect During Data Transfer bit is set to 1 the value returned is 28000h 160 KBytes See Chapter 12 for more information about the ND bit Bytes 04 and 05 Minimum Block Length The value returned for the Minimum Block Length field is 0001h 1 byte 16 2 510201 17 READ BUFFER 3Ch Bit 7 6 5 4 3 1 0 Byte 00 0 0 1 1 1 0 0 01 Logical Unit Number Reserved Mode 02 Buffer ID 03 MSB 04 Buffer Offset 05 LSB 06 MSB 07 Allocation Length 08 LSB 09 Vendor Unique Reserved 0 0 The READ BUFFER command is used to copy the EXB 8500 s microcode across the SCSI bus to the initiator This command is used with the WRITE BUFFER 3Bh command to copy the microcode from one EXB 8500 to other EXB 8500s To copy microcode from one EXB 8500 to another EXB 8500 follow these steps 1 Issue a READ BUFFER command to place the EXB 8500 s microcode into the correct format and to transfer the microcode image across the SCSI bus to the initiator 2 Issue a WRITE BUFFER command to copy the microcode from the initiator to other EXB 8500s For information about using the WRITE BUFFER command refer to Chapter 29 17 1 Field Definitions Byte 01 Bits 2 through 0 Mode The Mode field determines the type of operatio
112. DE bit set to 0 to move from the directory to the data area of the tape In this case the EXB 8500 spaces over the first EOD mark as long as it is located before the first filemark and does not return Check Condition status However when the EXB 8500 detects the second EOD mark at the end of data it returns Check Condition status with the sense key set to Blank Check 8h PEOT Encountered If the Code field has a value of 000 001b or 011b and the physical end of tape PEOT is encountered the EXB 8500 returns Check Condition status The EOM Valid and PEOT bits are set in the extended sense data with the sense key set to Medium Error 3h The Information bytes are set to the difference between the requested number of blocks or filemarks and the actual number of blocks or filemarks spaced over Note Ifthe Code field has a value of 011b the Information bytes are invalid PBOT Encountered If the Code field has a value of 000 or 001b and the physical beginning of tape PBOT is encountered the EXB 8500 returns Check Condition status The EOM LBOT and Valid bits are set in the extended sense data with the sense key set to No Sense The tape is positioned at LBOT The Information bytes are set to the difference between the requested number of blocks or filemarks and the actual number of blocks or filemarks spaced over Note that since the error was encountered during a space backward operation the value in the Information bytes is
113. Data Protect 7h LEOT Encountered If the logical end of tape LEOT is encountered the EXB 8500 attempts to write all of the filemarks requested and then returns Check Condition status The EOM bit is set to 1 and the LBOT bit is set to 0 in the extended sense data with the sense key set to No Sense If the EXB 8500 has successfully written all of the data in the buffer and the requested number of filemarks to tape the Valid bit is not set Issuing a WRITE FILEMARKS command after LEOT is encountered causes the EXB 8500 to return Check Condition status after the command is completed The EOM bit is set to 1 and the LBOT bit is set to O in the extended sense data with the sense key set to No Sense If the EXB 8500 has successfully written all of the data in the buffer and the requested number of filemarks to tape the Valid bit is set PEOT Encountered If the physical end of tape PEOT is encountered the EXB 8500 terminates the WRITE FILEMARKS command and returns Check Condition status The EOM and PEOT bits are set in the extended sense data with the sense key set to Volume Overflow Dh If the Valid bit is set to 1 the Information bytes contain the difference between the requested number of filemarks and the actual number of filemarks written 30 4 510201 December 1991 30 WRITE FILEMARKS 10h Unrecoverable Error If an unrecoverable media or hardware error occurs during the write filemarks operation the EXB 8500 ter
114. Disallow disconnects Abort process Go Bus Free lt Continue processing C Rest No Operation Extended Message Go Bus Free Continue processing Process Extended message Execute warm reset Message Reject or Initiator Detected Error Send Message Reject IN Set sense key to Aborted Command Bh Continue processing Go to Status phase Send Check Condition Figure 6 4 Message Processing after the Command Phase and before the Data In December 1991 6 19 6 SCSI Physical Path Communications 6 20 Processing of Extended Message Out Figure 6 5 shows how Extended Message Out messages are processed Note that the Attention signal must coincide with the message byte numbering sequence The EXB 8500 responds to the initiator s Synchronous Data Transfer Request with a transfer period of xx or 3Eh 250 nanoseconds whichever is larger slower and a REQ ACK offset of yy or 12 whichever is smaller Parity Error in Extended Message Out When parity checking is enabled and the EXB 8500 detects a parity error in the Synchronous Data Transfer Request message received from the initiator the EXB 8500 stays in the Message Out phase until the Attention signal goes low Then it goes to the Message Out phase again to request that the initiator reissue the entire message sequence 510201 6 SCSI Physical Path Communications E
115. ESULTS 1Ch 19 3 Receiving a Trace Dump This section describes the steps and bit settings for receiving a trace dump Trace dumps are used for detailed fault analysis and include a history of SCSI and servo command activity for the EXB 8500 To receive a trace dump follow these steps 1 Issue a SEND DIAGNOSTIC command with the SelfTest DevOfL and UntOfL bits set to 0 and the MD bit set to 1 The Parameter List Length field is ignored and can have any value 2 Immediately issue a RECEIVE DIAGNOSTIC RESULTS command with the Allocation Length field set to 500h 1 280 bytes and the TD bit set to 1 Note ensure that data in the trace dump is valid be sure that the RECEIVE DIAGNOSTIC RESULTS command immediately follows the SEND DIAGNOSTIC command and that the EXB 8500 is reserved for the initiator s exclusive use As shown in Table 19 4 1 280 bytes of information are returned in the trace dump Table 19 4 Bytes Returned in a Trace Dump Bytes Contain this data 0 to 255 SCSI Instruction Trace Table 256 to 511 SCSI State Trace Table Servo Instruction Status Extended 512 to 1 279 Status Tables As described in the next section you can use the SCSI instruction trace table bytes 0 to 255 to analyze SCSI command execution sequences Interpreting the other two sections of the trace dump bytes 256 to 1 279 however requires more sophisticated analysis procedures that are beyond the scope of this manual 19 6
116. EXB 8500 8mm Cartridge Tape Subsystem User s Manual zExabyte 510201 002 Copyright Copyright 1991 EXABYTE Corporation All rights reserved This item and the information contained herein are the property of EXABYTE Corporation No part of this document may be reproduced transmitted transcribed stored in a retrieval system or translated into any language or computer language in any form or by any means electronic mechanical magnetic optical chemical manual or otherwise without the express written permission of EXABYTE Corporation 1685 38th Street Boulder Colorado 80301 Disclaimer EXABYTE Corporation makes no representation or warranties with respect to the contents of this document and specifically disclaims any implied warranties of merchantability or fitness for any particular purpose Further EXABYTE Corporation reserves the right to revise this publication without obligation to notify any person or organization of such revision or changes Trademark Notices EXABYTE is a registered trademark and EXATAPE is a trademark of EXABYTE Corporation Amphenol is a registered trademark of Amphenol Corporation dataMate is a registered trademark of Methode Electronics Inc Molex is a trademark of Molex Incorporated Revision History Previous revisions of this manual include the following Revision Date 000 December 1990 001 April 1991 002 December 1991 For information about the changes and enhancement
117. FER Notes 29 6 510201 30 WRITE FILEMARKS 10h Bit 7 6 5 4 3 2 1 0 Byte 00 0 0 0 1 0 0 0 0 01 Logical Unit Number Reserved WSmk Immed 02 MSB 03 Number of Filemarks 04 LSB 05 Short VU Reserved 0 0 The WRITE FILEMARKS command causes the EXB 8500 to write any data remaining in the buffer to tape and then to write one or more filemarks to tape Note If the disconnect option is enabled the EXB 8500 can disconnect from the initiator while the WRITE FILEMARKS command is executing 30 1 Field Definitions Byte 01 Bit 1 WSmk This bit is not supported by the EXB 8500 The valid value for this bit is 0 Byte 01 Bit 0 Immed The Immediate bit is used to determine when command status is returned to the initiator as follows 0 Status is reported to the initiator when the WRITE FILEMARKS command is completed All buffered data and filemarks are written to the tape before the command is completed Note In EXB 8500 format filemarks can be buffered Each buffered filemark uses 1 KByte of the EXB 8500 s 1 MByte buffer 1 Status is reported to the initiator when the WRITE FILEMARKS command is initiated by the EXB 8500 This mode is valid only if buffered mode is returned in the MODE SENSE parameter header Note When the Density Code indicates EXB 8200 format the Immediate bit is ignored and assumed to be 0 December
118. Figure 6 11 shows how messages are processed during the Status In phase Note that attempts to change the physical path characteristics are not processed Initial Phase Status In Transition to Message Out Does initiator own current process No Abort process Go Bus Free HF Message Reject Send Message Reject IN l Set sense key to Aborted Command Bh Go to Message In phase Send Command Complete Go Bus Free Initiator Dete Error Execute warm reset No Operation Continue processing Figure 6 11 Message Processing during the Status In Phase December 1991 Send Restore Pointers IN Go to Status ph again All others Send Message Re Set sense key Aborted Comman Go to Status phase Send Check Con 6 33 6 SCSI Physical Path Communications Message Processing in Message In Phase Command Complete Figure 6 12 shows how messages are processed while the EXB 8500 is attempting to send the Command Complete message Parity Error Sending the Command Complete Message In If the initiator detects a parity error during the Command Complete Message In phase it sends a Message Parity Error message to the EXB 8500 The EXB 8500 responds by re sending the Command Complete message The initiator should count Message Parity Error messages to qualify the communic
119. ITE FILEMARKS 10h non immediate SPACE 11h in either direction ERASE 19h LOAD UNLOAD 1Bh LOCATE 2Bh in the reverse direction LH Dr tu m The operator presses the unload button m The time specified for the Write Delay Time field in the MODE SELECT command elapses note however if the Write Delay Time field is 0 a partially full buffer is not flushed to tape Note The Write Delay Time field can be set for PF 1 format only see Section 12 8 for more information 28 4 510201 28 WRITE 0Ah 28 4 Exceptions and Error Conditions The following exceptions and error conditions can occur with the WRITE command LEOT Encountered As described in Table 28 1 on the next page if LEOT is encountered during a WRITE command the action of the EXB 8500 depends on m The setting of the Fixed bit in the current CDB m Whether LEOT was encountered during the current write operation or during a previous write operation buffered mode December 1991 28 5 28 WRITE 0Ah Table 28 1 Action of EXB 8500 If LEOT Is Encountered during a WRITE Command Setting of Fixed bit in current CDB Fixed 0 variable length logical block Fixed 1 fixed length logical blocks LEOT encountered during current write operation The EXB 8500 returns Check Condition status after all data has been written to tape The extended sense data is set as follows Error Code 70h EOM 1 Sense Key 0h No Sense LBOT 0
120. NIT READY 00h command The EXB 8500 must return Check Condition status Then issue a REQUEST SENSE command The sense key must be set to Not Ready no data cartridge present CAUTION When performing this test be sure to use a data cartridge that does not contain needed data scratch data cartridge Data on the tape will be destroyed during the write portion of this test December 1991 24 5 24 SEND DIAGNOSTIC 1 Test 110 Power on Tests with Tape During this test the EXB 8500 performs its power on RAM and servo diagnostic tests If these tests complete successfully the EXB 8500 returns Good status and positions the tape at LBOT Improper test setup causes the EXB 8500 to return Check Condition status with the sense key set to Illegal Request The EXB 8500 disconnects during this test Note Test 110 cancels all synchronous negotiations and erases the trace tables In addition the unload button is disabled during this test Setup for Test 110 Before starting this test power the EXB 8500 on and insert a write enabled scratch data cartridge Issue a TEST UNIT READY 00h command The EXB 8500 must return Good status Test 111 Power on Write Read and Load Tests with Tape During this test the EXB 8500 first performs its power on RAM and servo diagnostic tests If these tests complete successfully the EXB 8500 continues by performing the following operations Writes internally generated data to the
121. ODE SENSE command to indicate that the EXB 8500 does not support data compression The valid value for this bit is 0 Byte 02 Bits 5 through 0 Reserved These bits are reserved Byte 03 Bit 7 DDE Data Decompression Enable The EXB 8500 does not support data decompression so the valid value for the Data Decompression Enable bit is 0 Byte 03 Bits 6 and 5 RED Report Exception on Decompression The EXB 8500 does not support data compression so the valid value for the Report Exception on Decompression field is 00 Byte 03 Bits 4 through 0 Reserved These bits are reserved Bytes 04 through 07 Compression Algorithm The only valid value for the Compression Algorithm field is 0 Bytes 08 through 11 Decompression Algorithm The only valid value for the Decompression Algorithm field is 0 Bytes 12 through 15 Reserved These bytes are reserved 12 23 12 MODE SELECT 15h 12 8 Device Configuration Page Page Codez 10h Page Format Bit 7 6 5 4 3 2 1 0 Byte 00 Reserved Page Code 01 Page Length 02 RSVD CAP CAF Active Format 03 Active Partition 04 Write Buffer Full Ratio 05 Read Buffer Empty Ratio a Write Delay Time 07 LSB 08 DBR BIS RSmk AVC SOCF RBO REW 09 Gap Size 10 EOD Defined EEG SEW Reserved 11 MSB Buffer Size at Early Warning 13 LSB 14 Select Data Compression Algori
122. ON commands to the directory 8 Repeat steps 4 through 7 for successive data sets until the tape is full or until there is no more data to be written READ READ READ POSITION POSITION READ POSITION POSITION LBOT DIRECTORY PAD 12 MBYTE PAD DS 1 DIR1 DSn DIR n write the write the data set data set write the write the directory directory 510201 Appendix B 8500 Directory Support 9 Rewind the tape to LBOT This creates an EOD mark after the last data on the tape EOD 2 10 Create a master directory in the directory pad at the beginning of the tape Write the data returned from the READ POSITION command issued in step 6 and each iteration of that step to this directory The amount of data you can write to this directory is limited to the size of the directory pad no more than 20 MBytes The resulting master directory lists the starting location of the directory DIR n for each data set on the tape 1 Rewind the tape to LBOT This creates an EOD mark at the end of the master directory EOD 1 that overwrites most of the 12 MByte pad LBOT MASTER DIR 001 PAD LFM DS 1 DIR1 D5n DIR n EOD2 1 Rewind 2 Write the master the tape directory Note After writing the master directory be sure to rewind the tape
123. Page Code The Page Code identifies the type of MODE SENSE data being transferred This is the Disconnect Reconnect Page The value returned for the Page Code is 02h Byte 01 Page Length The Page Length indicates the number of Disconnect Reconnect Page bytes that follow this byte The value returned for this byte is OAh Byte 02 Buffer Full Ratio The Buffer Full Ratio represents the amount of data that must be present in the buffer during a buffered read operation before the EXB 8500 will attempt to reconnect to the initiator The value is expressed in 4 KByte increments The default value for this byte is 80h 512 KBytes Values range from 20h to DOh 128 to 832 KBytes 13 21 13 MODE SENSE Byte 03 Buffer Empty Ratio The Buffer Empty Ratio indicates how empty the buffer must be during a buffered write operation before the EXB 8500 will attempt to reconnect to the initiator The value is expressed in 4 KByte increments The default value for this byte is 80h 512 KBytes Values range from 20h to DOh 128 to 832 KBytes The Buffer Empty Ratio equals the Buffer Full Ratio Note The Buffer Full Ratio and the Buffer Empty Ratio in the Disconnect Reconnect Page page format are equivalent to the Reconnect Threshold byte in the vendor unique parameters for non page format Bytes 04 and 05 Bus Inactivity Limit The value returned for the Bus Inactivity Limit is 0 The EXB 8500 uses 0 as a default value meaning t
124. Page Codez20h Page Format Bit 7 6 5 4 3 2 1 0 Byte 00 Reserved Page Code 01 Page Length 02 CT RSVD ND RSVD NBE EBD PE NAL 03 RTF WTF RSVD P5 04 Motion Threshold 05 Gap Threshold Field Definitions This page applies only to page format that is when the PF bit in the CDB is set to 1 Byte 00 Bits 5 through 0 Page Code The Page Code identifies the type of MODE SELECT page being transferred This is the Vendor Unique Parameters Page 1 The valid value for Page Code is 20h Byte 01 Page Length The Page Length indicates the number of bytes in the Vendor Unique Parameters Page 1 that follow this byte The valid value for this byte is 04h Byte 02 Bit 7 CT Cartridge Type This bit defines what type of data cartridge is expected to be loaded 0 P6 Cartridge Type Domestic 1 PI Cartridge Type International P5 P6 LEOT equivalency Note You can set the CT bit only when the tape is positioned at LBOT Refer to Appendix C for information about data cartridge capacities and for an explanation of how the EXB 8500 autosizes data cartridges For information about changing the power on default for the cartridge type refer to Section 3 4 December 1991 12 29 12 MODE SELECT 15h Byte 02 Bit 5 ND This bit indicates whether the EXB 8500 can disconnect from the initiator during the data transfer phase 0 The EXB 8500 can di
125. SELECT 15h Byte 00 Bit 5 ND No Disconnect During Data Transfer This bit indicates whether the EXB 8500 can disconnect from the initiator during the data transfer phase 0 The EXB 8500 can disconnect from the initiator during the data transfer phase The EXB 8500 will not disconnect during the data transfer phase The power on default for the ND bit is 0 Restrictions when the ND bit is 0 m The maximum logical block size allowed in fixed or variable mode is 240 KBytes 3C000h Restrictions when the ND bit is 1 m Ifthe logical block size specified by the Block Length field in the Block Descriptor is greater than 160 KBytes 28000h setting the ND bit to 1 causes the EXB 8500 to return Check Condition status with the sense key set to Illegal Request 5h m The total number of bytes that can be transferred as a result of a single WRITE or READ command in fixed or variable mode is 160 KBytes 28000h That is the total transfer length specified by the CDB must be 160 KBytes or less m During a write operation the data transfer from the initiator does not start until the number of bytes of available space in the EXB 8500 s buffer is greater than or equal to the total transfer length specified by the CDB m During a read operation the data transfer to the initiator does not start until all of the data requested by the CDB up to a total transfer length of 160 KBytes is resident in the EXB 8500 s buffer m If the
126. Thresholds Table 3 3 provides summary information about the motion and reconnect thresholds As shown in the table the default value for both the motion threshold and the reconnect threshold is 80h The 80h default is in the middle of the 1 MByte buffer which serves to optimize an initiator transfer rate of 500 KBytes second Table 3 3 Motion Threshold and Reconnect Threshold Summary Default What it During a write During a read value controls operation operation Starting and Amount of data in Space available Motion 80h stopping of tape buffer controls in buffer controls Threshold 512 KBytes motion when data is when data is buffer tape transferred to the transferred from transfers tape the tape Rate of disconnects and Space available Amount of data in reconnects in buffer controls buffer controls Reconnect 80h between the when the when the Threshold 512 KBytes EXB 8500 and EXB 8500 EXB 8500 the initiator reconnects to the reconnects to the initiator buffer initiator initiator transfers December 1991 3 Operating the 8500 3 3 EXB 8500 Directory Support 3 10 The EXB 8500 directory support feature is an optional feature that requires a special EEPROM image available from EXABYTE This option is not set in standard EXB 8500s You can use the directory support feature to maintain a directory at the beginning of an EXB 8500 format tape This directory indicates
127. a Message Parity Error message to the EXB 8500 The EXB 8500 responds by re sending the Disconnect or Save Data Pointers message The initiator should count Message Parity Error messages to qualify the communication If the count exceeds some threshold the initiator should clear the EXB 8500 from the bus by doing one of the following m Sending the Abort message m Performing a SCSI bus reset m Sending the Bus Device Reset message 6 37 6 SCSI Physical Path Communications Initial Phase Message In Sending Save Data Pointers or Disconnect Transition to Message Out Go Bus Free Does initiator own current process Execute warm reset Continue processing Abort process Go Bus Free Error Message Reject Message Parity C Allothers y Disallow disconnects Send Message Reject IN d Send Save Data Pointers Send Save Data Pointers Skip Disconnect phase or Disconnect message or Disconnect message again again Continue processing Continue processing Continue processing Figure 6 14 Message Processing while EXB 8500 Is Executing Disconnect Sequence 6 38 510201 6 SCSI Physical Path Communications 6 4 Unit Attention A Unit Attention condition is created for each initiator when any of the following conditions occurs m The EXB 8500 is reset whether by a Bus Device Reset message a SCSI bus reset or a p
128. ace 2 SCSI 2 Specification provides detailed information about SCSI physical characteristics As described in that specification SCSI devices can be daisy chained together using a common cable Both ends of the cable must be terminated All signals are common between all bus devices The EXB 8500 supports the following SCSI characteristics Asynchronous data transfer rates of up to 1 5 MBytes second Synchronous data transfer rates of up to 4 0 MBytes second Sustained data transfer rate of up to 500 KBytes second Single ended or differential SCSI configurations SCSI 2 or SCSI 1 command set sequential access device 6 3 6 SCSI Physical Path Communications 6 1 Message System The message system allows communication between the initiator and the EXB 8500 for physical path management Table 6 1 lists the messages supported by the EXB 8500 Table 6 1 Messages Supported by the EXB 8500 Direction Hex Value Message Out 00h Command Complete Extended Message Synchronous Data otk Transfer Request 02h Save Data Pointers 03h Restore Pointers 04h Disconnect 05h Initiator Detected Error 06h Abort 07h Message Reject 08h No Operation 09h Message Parity Error OCh Bus Device Reset 80h Identify n EXB 8500 to initiator Out Initiator to EXB 8500 Command Complete 00h The EXB 8500 sends the Command Complete message to the initiator to indica
129. ad Retry Count indicates how many times the EXB 8500 will attempt its read recovery algorithms before an unrecoverable read error is reported The values returned this field can range from 00h to OBh The default is OBh Byte 08 Write Retry Count The Write Retry Count field specifies how many times the EXB 8500 should rewrite a physical block before an unrecoverable write error is reported The values for this field are 00h and OBh The default value is OBh A value of 0 for the Write Retry Count indicates that the EXB 8500 will not rewrite any physical blocks during a write operation and will continue to write additional data If this value is used the EXB 8500 may not be able to recover the data written on the tape since its write integrity cannot be guaranteed 510201 13 MODE SENSE 13 6 Disconnect Reconnect Page Page Code 02h Bit 7 6 5 4 3 2 1 0 Byte 00 Reserved Page Code 01 Page Length 02 Buffer Full Ratio 03 Buffer Empty Ratio 04 MSB D Bus Inactivity Limit 05 LSB 06 MSB od Disconnect Time Limit 07 LSB 08 MSB Te Connect Time Limit 09 LSB 10 MSB Maximum Burst Size 11 LSB December 1991 Field Definitions The Disconnect Reconnect Page specifies parameters for disconnects and reconnects This page is returned only when the Page Code field in the CDB is set to 02h or 3Fh Byte 00 Bits 5 through 0
130. age Out Phase after Command Phase 6 18 Processing of Extended Message Out 6 20 Processing of Extended Message In v3 env ee OOS 6 22 Message Processing in Data Out Phase WRITE Command 6 24 Message Processing in Data Out Phase Information Commands 6 26 Message Processing in Data In Phase READ Command 6 28 Message Processing in Data In Phase Information Commands 6 30 Message Processing In Status In Phase s x 6 32 Message Processing in Message In Phase Command Complete 6 33 Message Processing after Reselecti 2 4 4424443453 Roe 6 34 Message Processing during Disconnect Sequence 6 36 04 Unit cnc s s oe meok Bi ee we Se we RM ee ee eR 6 38 viii 510201 Effect of Changing Data Cartridges 2c oz 6 38 Clearing the Unit Attention Condition 6 39 6 5 Resetting the EXB S500 a eae oe Y dae Se Ss 6 40 Effect of Power on Reset uuu oce a be he eR wee he PE Bod d 6 40 Effect of SCSI Bus and Device Resets 524444828465 24244 6 41 Reset Processing wc koe v xw 6E rS 6 41 7 EXB 8500 SCSI Command Set 7 1 EAM Command Format PEDE 7 2 Command Descriptor Block for Six Byte Command 7 2 Command Descriptor Block for Ten Byte Command 7 3 Format of the Operation Code i
131. alue of 011b space to end of data the Count field is ignored The forward search continues until the EXB 8500 encounters EOD The tape is positioned so that a subsequent WRITE command can append data after the last block or filemark written before EOD Note Attempting to space to EOD on a tape written in EXB 8200 format results in Check Condition status The sense key will be set to Illegal Request 5h December 1991 25 5 25 SPACE 11h Notes 25 6 510201 26 TEST UNIT READY 00h Bit 7 6 5 4 2 1 0 Byte 00 0 0 0 0 0 0 0 01 Logical Unit Number Reserved 02 03 Reserved 04 05 Vendor Unique Reserved 0 0 26 1 Field Definitions The TEST UNIT READY command provides a means for determining if the EXB 8500 is ready to accept an appropriate medium access command The TEST UNIT READY command returns Good status if the EXB 8500 is ready to accept a medium access command without returning Check Condition status The TEST UNIT READY command returns Check Condition status with the sense key set to Not Ready 2h if the EXB 8500 is not ready to accept a medium access command Note TEST UNIT READY command is not a request for a unit self test Byte 05 Bits 7 and 6 Vendor Unique There are no vendor unique definitions for this command December 1991 26 1 26 TEST UNIT READY 00h Notes 26 2 510201 27 VERIFY 13h
132. an occur with the WRITE BUFFER command Aborting a WRITE BUFFER Command or Command Sequence To terminate a WRITE BUFFER command or an entire sequence of WRITE BUFFER commands send an Abort message to the EXB 8500 This will reset the EXB 8500 Then reissue the WRITE BUFFER command or the entire sequence of WRITE BUFFER commands Microcode Not Valid If the data downloaded from the SCSI bus is not valid the EXB 8500 returns Check Condition status with the sense key set to Medium Error 3h The EXB 8500 will not attempt to load the new code If this occurs make sure you have the correct file and try again or load new microcode using a microcode update tape refer to Chapter 5 or the CTS Monitor program refer to the Monitor User s Guide Fatal Load Error Once the load process is started it is irreversible If a hardware or power failure occurs during the load operation the EXB 8500 may not be able to operate In this event use the CTS Monitor program to reload the microcode through the Monitor port Refer to the Monitor User s Guide for complete instructions Illegal Request If you issue a command other than WRITE BUFFER INQUIRY or REQUEST SENSE to the EXB 8500 during a WRITE BUFFER command sequence the EXB 8500 terminates the command with Check Condition status The sense key is set to Illegal Request 5h and the ASC and ASCQ are set to O0h 00h The Fault Symptom Code is set to EBh December 1991 29 5 29 WRITE BUF
133. ape PEOT is encountered the EXB 8500 returns Check Condition status The EOM and PEOT bits are set in the extended sense data with the sense key set to Medium Error 3h When the VERIFY command terminates the logical position is not defined If the Valid bit is set to 1 the Information bytes are set to either of the following m The requested verification length if the Fixed bit is set to 0 m The difference between the requested verification length and the actual number of blocks verified if the Fixed bit is set to 1 Unrecoverable Error If an unrecoverable media or hardware error occurs during the verify operation the EXB 8500 terminates the VERIFY command and returns Check Condition status The sense key indicates a Medium Error 3h or Hardware Error 4h Indicators in the extended sense data can be used to isolate the error condition When the VERIFY command is terminated the EXB 8500 is positioned after the unrecovered block for a media error or in an undefined position for a hardware error If the Valid bit is set to 1 the Information bytes are set to either of the following m The requested verification length if the Fixed bit is set to 0 m The difference between the requested verification length and the actual number of blocks verified if the Fixed bit is set to 1 Note that the actual number does not include the unrecovered block In both fixed and variable block modes the EXB 8500 may have entered the Data
134. arty reservation is requested Byte 01 Bits 3 through 1 Third Party Dev ID The Third Party Dev ID field indicates the SCSI ID of the device for which the initiator is making the third party reservation Byte 05 Bits 7 and 6 Vendor Unique There are no vendor unique definitions for this command December 1991 22 1 22 RESERVE UNIT 16h Notes 22 2 510201 23 REWIND 01h Bit 7 6 5 4 3 2 1 0 Byte 00 0 0 0 0 0 0 0 1 01 Logical Unit Number Reserved Immed 02 03 Reserved 04 05 Vendor Unique Reserved 0 0 The REWIND command causes the EXB 8500 to rewind the tape to the logical beginning of tape LBOT Notes m Ifthe disconnect option is enabled the EXB 8500 disconnects from the initiator while the REWIND command is executing m Ifthe REWIND command is received after a WRITE OAh or WRITE FILEMARKS 10h command buffered data and filemarks are written to the tape before it is rewound m Ifan error occurs during the writing of the data in the buffer to the tape the EXB 8500 returns Check Condition status The rewind operation is not performed The initiator should issue a REQUEST SENSE 03h command to determine the cause of the error m Ifthe tape is already at LBOT and there is no data in the buffer no tape motion results m If acommand is received by the EXB 8500 while the tape is rewinding the EXB 8500 executes the command a
135. at and EXB 8200 format logical blocks can have fixed or variable lengths In addition both formats support logical block sizes from 0 to 240 KBytes In EXB 8500 format each 1 024 byte physical block can contain multiple logical blocks for example two 512 byte logical blocks can be written in one physical block In addition a logical block can start in one physical block and end in a different physical block This logical block packing prevents the loss of data capacity for tapes with small logical blocks written in EXB 8500 format 510201 December 1991 3 Operating the EXB 8500 Note In EXB 8200 format only one logical block can be written in each physical block For detailed information about logical block packing in EXB 8500 format refer to the EXB 8500 8mm Cartridge Tape Subsystem Product Specification Search Fields A track written in EXB 8500 format also contains search fields that enable the EXB 8500 to perform high speed searches at up to 75 times the nominal tape speed A high speed search occurs when the initiator issues a LOCATE 2Bh or SPACE 11h command The search fields are the only areas of the tape that are read during a high speed search They consist of small data areas interspersed with clock sync areas The search field data contains information for locating files and blocks and detecting the end of data EOD mark during high speed searches Note Tapes written in EXB 8200 format do not contain search
136. ata transfer The EXB 8500 is positioned at the start of the next block After aborting the data transfer the EXB 8500 sends Check Condition status to the initiator followed by a Command Complete message The sense key is set to Aborted Command Bh and the ASC and ASCQ are set to 47h and 00h The SCSI Bus Parity Error bit is set to 1 In fixed block mode the Information bytes contain the number of blocks not sent to the initiator The initiator should backspace n blocks and attempt to reread the blocks by reissuing the READ command 6 29 6 SCSI Physical Path Communications Initial Phase Data In Transition to Message Out Read data from tape Go Bus Free Continue processing Does initiator own current Execute warm reset process Abort process Go Bus Free lt Initiator Detected Error Y Abort process Abort process Set sense key to Send Message Reject IN Aborted Command Bh Y Set sense key Set Info bytes Aborted Command Bh set Valid bit Go to Status phase Go to Status phase Send Check Condition Send Check Condition Figure 6 9 Message Processing during the Data In Phase of a READ Command 6 30 510201 December 1991 6 SCSI Physical Path Communications Message Processing in Data In Phase Information Commands Figure 6 10 shows how messages are processed during the Data In phase for commands
137. ates a Medium Error 3h or Hardware Error 4h Indicators in the extended sense data can be used to isolate the error condition When the LOCATE command is terminated the position of the EXB 8500 depends on whether the locate operation was in the forward or reverse direction m If the error occurred during a locate operation in the forward direction the EXB 8500 is positioned after the unrecovered block m If the error occurred during a locate operation in the reverse direction the EXB 8500 is positioned before or after the unrecovered block If the Valid bit is set to 1 the Information bytes indicate the difference between the requested logical position and the actual logical position Note that the Information bytes may be positive or negative Illegal Requests The following conditions cause the EXB 8500 to return Check Condition status with the sense key set to Illegal Request 5h m A locate operation in the forward direction is attempted immediately after a WRITE or WRITE FILEMARKS command has been executed m ALOCATE command is attempted on a tape written in EXB 8200 format 11 5 11 LOCATE 2Bh Notes 11 6 510201 12 MODE SELECT 15h Bit 7 6 5 4 3 2 1 0 Byte 00 0 0 0 1 0 1 0 1 01 Logical Unit Number Reserved SP 02 Reserved 03 04 Parameter List Length 05 Vendor Unique Reserved 0 0 The MODE SELECT command allows the
138. ation If the count exceeds some threshold the initiator should clear the EXB 8500 from the bus by doing one of the following m Sending the Abort message m Performing a SCSI bus reset m Sending the Bus Device Reset message Initial Phase Message In Command Complete Transition to Message Out Set sense key to Go Bus Free Aborted Command Bh Go Bus Free Execute warm reset Message Parity CAII others _ Error Go Bus Free Send Command Complete again Go Bus Free Figure 6 12 Message Processing during Command Complete Message In Phase 6 34 510201 December 1991 6 SCSI Physical Path Communications Message Processing after Reselection Figure 6 13 shows how messages are processed after the EXB 8500 has reselected the initiator and sent the Identify message in Note that if the initiator sends the EXB 8500 a Message Reject message this will be treated as a catastrophic error committed by the initiator Parity Error Sending the Identify Message In If the initiator detects a parity error when the EXB 8500 sends the Identify message in it responds by sending a Message Parity Error message to the EXB 8500 The EXB 8500 responds by re sending the Identify message The initiator should count Message Parity Error messages to qualify the communication If the count exceeds some threshold the initiator should clear the EXB 8500 from the bus by doing one of the following
139. ayed asking if the EXB 8500 15 idle and ready to create a firmware load tape Press Y if the EXB 8500 is idle and you want to continue press N to cancel the operation After you press Y the amber light will begin to flash slowly about 1 blink per second and will continue to flash for the duration of the make microcode tape process If there is a tape in the EXB 8500 the tape 15 ejected to prevent the EXB 8500 from writing over a good tape 510201 December 1991 5 Loading New Microcode from Tape 5 Insert a new tape in the EXB 8500 Note Once a tape has been made into a microcode update tape it cannot be reused as a data tape To avoid wasting tape use a 15m tape If necessary you can use a previously written data tape or microcode update tape to create a new microcode update tape When the tape is inserted the EXB 8500 loads it and copies its control code servo code and EEPROM code if specified to the tape If the tape is made successfully the EXB 8500 unloads and ejects the tape and the following message is displayed in the CTS Monitor program G Load tape made successfully and tape ejected Remove the tape from the EXB 8500 label it as a microcode update tape and store it in a safe location to prevent it from being used inadvertently Note If an error occurs while the EXB 8500 is making the microcode update tape the amber light will flash at a faster rate about 4 blinks per second and the tape will no
140. be changed with a MODE SELECT command Start Stop Write Operation In a start stop write operation the initiator to buffer transfer speed is slower than the buffer to tape transfer speed that is data transfers from the initiator occur at less than 500 KBytes per second In this mode of operation the motion threshold value represents the minimum amount of data in 4 KByte increments that must be in the EXB 8500 s 1 MByte buffer before tape motion will start and data will be written to tape Note Because of hardware requirements only one quarter of the buffer is used during write operations in EXB 8200 format For this reason the motion threshold for EXB 8200 write operations is expressed in 1 KByte increments When the motion threshold value is exceeded tape motion starts The write to tape operation continues until the buffer is empty and the tape motion stops Tape motion does not restart until the amount of data in the buffer once again exceeds the motion threshold value or until the buffer is flushed for some other reason such as a reverse tape motion command December 1991 3 7 3 Operating the 8500 Start Stop Read Operation In a start stop read operation the buffer to initiator transfer speed is slower than the tape to buffer transfer speed that is data transfers to the initiator occur at less than 500 KBytes per second In this mode of operation the motion threshold value represents the minimum amount of free
141. bit defines the type of read operation being performed as follows 0 A single logical block is read and the length of this block is specified in the Transfer Length field 1 One or more fixed length logical blocks are read and the number of blocks is specified in the Transfer Length field The length of each block is either the power on default block length or the length specified with the currently active MODE SELECT parameters bytes 5 through 7 of the Block Descriptor Note The EXB 8500 returns Check Condition status with the sense key set to Illegal Request 5h in the following cases m The Fixed field in the READ command is 0 variable length logical block and the Block Length field in the current MODE SELECT data is greater than 0 fixed length logical blocks m The Fixed field in the READ command is 1 fixed length logical blocks and the Block Length field in the current MODE SELECT data is 0 variable length logical block The ASC and ASCQ bits are set to 81h and OOh fixed variable mismatch 510201 December 1991 15 READ 08h Bytes 02 through 04 Transfer Length The Transfer Length field defines the amount of data to be read as follows m When the Fixed bit is set to 0 the Transfer Length field contains the length of the logical block in bytes The logical block can be any size from 0 to 240 Kbytes Note If the ND No Disconnect During Data Transfer bit is set the logical block can be any size
142. ble This bit is used to enable parity checking on the SCSI bus When this bit is set to 1 every byte received by the EXB 8500 is checked for parity 0 Parity checking disabled 1 Parity checking enabled The power on default for PE is 1 Note For information about changing the power on default for parity checking refer to Section 3 4 Byte 02 Bit 0 NAL No Auto Load This bit is used to disable the automatic loading of the tape into the tape path when a data cartridge is inserted into the EXB 8500 0 Auto loading enabled 1 Auto loading disabled The power on default value for NAL is 0 December 1991 12 31 12 MODE SELECT 15h Byte 03 Bits 7 through 5 RTF Read Tape Format These bits are ignored by the MODE SELECT command They are returned by the MODE SENSE command to indicate the current tape format Byte 03 Bits 4 through 2 WTF Write Tape Format These bits are ignored by the MODE SELECT command They are returned by the MODE SENSE command to indicate the format that will be used when the EXB 8500 writes data to the tape Byte 03 Bit 1 RSVD This bit is reserved Byte 03 Bit 0 P5 This bit is set to indicate that the data cartridge loaded in the EXB 8500 is expected to be a P5 European data cartridge When set to 1 this bit overrides the CT bit Note You can set the P5 bit only when the tape is positioned at LBOT Refer to Appendix C for information about data cartridge capacities an
143. bout directory support refer to Section 3 3 For a sample application showing how to use the EXB 8500 directory support feature refer to Appendix B 25 1 25 SPACE 11h 25 1 Field Definitions Byte 01 Bits 2 through 0 Code The Code field determines the type of space operation to be performed Table 25 lists the three combinations of bit settings in the Code field that are supported by the EXB 8500 Table 25 1 Code Values for the SPACE Command Bit 2 Bit 1 Bit 0 Meaning Space over n fixed or variable length 0 0 0 blocks 0 0 1 Space over n filemarks 0 1 1 Space to end of data valid for tapes written in EXB 8500 format only Bytes 02 through 04 Count The Count field represent the number of blocks or filemarks to be spaced over The value of n determines the direction of spacing as follows m A positive value of n in the Count field causes the EXB 8500 to space forward n blocks or filemarks When the space operation is complete the tape is logically positioned on the EOT side of the nth block or filemark m A negative value of n in 2s complement notation in the Count field causes the EXB 8500 to space backward over n blocks or filemarks When the space operation is complete the tape is logically positioned on the BOT side of the nth block or filemark m A value of 0 in the Count field causes no change in the tape position and is not an error Note The Count field is ign
144. buffer Writes buffered data to the tape Rewinds the tape Reads data from the tape to the buffer Reads and verifies the data in the buffer Rewinds the tape If these operations complete successfully the EXB 8500 returns Good status and unloads and ejects the data cartridge If the PREVENT MEDIUM REMOVAL command has been issued it is overridden Improper test setup causes the EXB 8500 to return Check Condition status with the sense key set to Illegal Request The EXB 8500 disconnects during this test Note Test 111 cancels all synchronous negotiations and erases the trace tables In addition the unload button is disabled during this test 24 6 510201 24 SEND DIAGNOSTIC 1 Setup for Test 111 Before starting this test power the EXB 8500 on and insert a write enabled scratch data cartridge Issue a TEST UNIT READY 00h command The EXB 8500 must return Good status Then issue a REQUEST SENSE command The EOM and LBOT bits must be set to indicate that the tape is positioned at LBOT CAUTION When performing this test be sure to use a data cartridge that does not contain needed data Data on the tape will be destroyed during the write portion of this test Note Data created during SEND DIAGNOSTIC tests cannot be interpreted by normal EXB 8500 read operations However the tape can be reused for normal use December 1991 24 7 24 SEND DIAGNOSTIC 1 Notes 24 8 510201 25 SPACE 11h
145. buffered write operation tape motion begins and data is written to the tape When the buffer is emptied to this point during a buffered read operation tape motion begins and data is read filling the empty portion of the buffer with new data from the tape Byte 03 Reconnect Threshold The value in the Reconnect Threshold byte indicates the amount of data that must be in the buffer before the EXB 8500 reconnects to the initiator for a buffered write or read operation The value is expressed in 4 KByte increments The default is 80h 512 KBytes Valid values range from 20h to DOh 128 to 832 KBytes When this amount of free space is available in the buffer during a buffered write operation the EXB 8500 reconnects to the initiator to accept additional data When the buffer fills to this level during a buffered read operation the EXB 8500 reconnects to the initiator and data 15 transferred Note Ifthe ND bit is 1 and you set the Reconnect Threshold byte to a value less than AOh or greater than COh the value will automatically be changed to AOh If however you set the Reconnect Threshold byte to a value between AOh and COh that value will take effect If the ND bit is 0 the Reconnect Threshold byte can have any value from 20h to DOh 128 to 832 KBytes For more information about the motion and reconnect thresholds see Section 3 2 December 1991 12 15 12 MODE SELECT 15h Byte 04 Gap Threshold The Gap Threshold byte speci
146. cannot be changed Note The disconnect time limit is determined by the minimum time it takes the EXB 8500 to disconnect from the SCSI bus and then initiate a reselection sequence The minimum disconnect time for the EXB 8500 is 265 usec The initiator cannot change this field so the value returned for this field by the MODE SENSE command is 0 510201 December 1991 12 MODE SELECT 15h Bytes 08 and 09 Connect Time Limit The EXB 8500 does not recognize any values other than 0 for the Connect Time Limit It uses O as a default value meaning that the EXB 8500 will disconnect from the bus after the amount of data defined by Maximum Burst Size has been transferred Bytes 10 and 11 Maximum Burst Size The Maximum Burst Size defines the amount of data to be transferred before disconnecting The value is expressed in increments of 512 bytes A value of 0 indicates that there is no limit to the amount of data transferred before disconnecting The EXB 8500 supports all values for this field The default value is 0 which means that disconnects and reconnects are performed using the value specified by the Buffer Full and Buffer Empty Ratios Note If you set the Maximum Burst Size field to a non zero value the EXB 8500 will automatically set the ND bit to 0 to allow disconnects during the data transfer phase That is Maximum Burst Size field has precedence over the ND bit For more information about the ND bit see Section 12 9 12 21
147. ck so that the EXB 8500 can determine which message has the parity error Bus Device Reset 0Ch The initiator sends the Bus Device Reset message to direct the EXB 8500 to reset all current I O operations This message forces the EXB 8500 to an initial state with no operations pending for any initiator Upon recognizing this message the EXB 8500 goes to the Bus Free phase Note Refer to Section 6 5 for more information about the effect of the Bus Device Reset message 510201 6 SCSI Physical Path Communications Identify 80h or COh Either the initiator or the EXB 8500 can send the Identify message The message is used to establish the physical path connection between an initiator and the EXB 8500 When the EXB 8500 sends the Identify message to the initiator during reconnection an implied Restore Pointers message must be implemented by the initiator before completion of this message Identify Message Bit Byte i 6 b 4 3 2 1 0 00 Identify DiscPriv LUNTAR Reserved LUNTRN Bit 7 Identify The Identify bit is set to 1 to distinguish the Identify message from all other messages Bit 6 DiscPriv The initiator sets the DiscPriv disconnect privilege bit to grant the EXB 8500 disconnect privileges 0 Disconnect is not allowed 1 Disconnect is allowed Bit 5 LUNTAR The EXB 8500 does not support this field the only valid value for this field is 0 Bits 2 t
148. ckaging obtained from your vendor Refer to the packing instructions in this manual If problems with the EXB 8500 occur contact your maintenance organization do not void the product warranty by allowing untrained or unauthorized personnel to attempt repairs December 1991 Changes and Enhancements to This Manual This revision of the EXB 8500 6mm Cartridge Tape Subsystem User s Manual includes the following changes and enhancements m Improved instructions in Section 2 4 for mounting the EXB 8500 m New instructions in Section 2 7 for performing the first power on if the EXB 8500 has been stored for more than six months m Revised information in Section 3 1 about the EXB 8500 s read write compatibility with other EXABYTE 8mm Cartridge Tape Subsystems m Revised information in Table 3 2 about filemarks including hexadecimal values for filemark lengths m New Section 3 3 describing the optional EXB 8500 directory support feature m Revised Table 3 5 showing EXB 8500 states indicated by LEDs m New Section 3 8 describing the unload button options a Modifications to Chapter 5 describing how to load new microcode from tape m New flowcharts in Chapter 6 describing EXB 8500 message processing m Revised and clarified information in Chapter 6 about recovering from SCSI bus parity errors m New Table 9 1 for the INQUIRY 12h command describing byte and bit settings m ADE bit added to the LOCATE 2Bh command Chapter 11 for t
149. command allows you to load new microcode from the SCSI bus into the EXB 8500 s control memories By setting the WBF bit byte 09 bit 7 you can specify that you are using one or more WRITE BUFFER commands to download new microcode Note You may want to issue more than one WRITE BUFFER command if the initiator has less than 176 KBytes of buffer space available When the WRITE BUFFER command or command sequence is executed the microcode is transferred from the SCSI bus to the EXB 8500 s RAM buffer Then the image in the buffer is validated During validation the microcode is checked for the following m Correct header format m Proper number of files m Correct format for each line Each line of code bytes must have a proper address data type and checksum m CRC match m Hardware boot code support for new microcode version If the new microcode passes these tests it is loaded into the EXB 8500 s control memories 29 1 29 WRITE BUFFER SBh Once the microcode is downloaded the machine state including MODE SELECT parameters is set to the new power on defaults and the EXB 8500 performs its power on self test Cautions for Using the WRITE BUFFER Command Be sure to follow these cautions when issuing the WRITE BUFFER command CAUTION The WRITE BUFFER command allows you to load new microcode from the SCSI bus into the EXB 8500 It is not intended to be used for testing EXB 8500 functionality that is
150. d be if LEOT had been encountered during the current WRITE operation Assumptions For the purposes of this example assume the following The initiator is issuing a series of buffered WRITE commands Each WRITE command transfers 100 fixed length blocks and each block is 1 KByte long that is each WRITE command transfers 100 KBytes of data The motion threshold is set to its default value of 512 KBytes 80h The EXB 8500 s buffer is empty Tape tension has been released but drum motion has not been suspended It will take approximately 1 5 seconds to re tension the tape before data can be written Less than 2 KBytes of space exist between the current tape position and LEOT Example T The initiator issues five buffered WRITE commands to the EXB 8500 WRITE 1 through WRITE 5 The 500 KBytes of data associated with these commands is transferred to EXB 8500 s buffer but it does not cause tape motion to begin this is because the 512 KByte motion threshold has not been exceeded After receiving the data for each command the EXB 8500 returns Good status to the initiator indicating that the command completed successfully 28 7 28 WRITE 0Ah The initiator issues a sixth buffered WRITE command to the EXB 8500 WRITE 6 The 100 KBytes of data associated with this command exceeds the motion threshold and causes the EXB 8500 to re tension the tape The EXB 8500 returns Good status to the initiator indicating that
151. d for an explanation of how the EXB 8500 autosizes data cartridges For information about changing the power on default for the cartridge type refer to Section 3 4 Byte 04 Motion Threshold The value in the Motion Threshold byte indicates the amount of data that must be in the buffer before tape motion is started for a buffered write or read operation The value is expressed in 4 KByte increments The default is 80h 512 KBytes Valid values range from 20h to DOh 128 to 832 KBytes When the buffer is filled to this point during a buffered write operation tape motion begins and data is written to the tape When the buffer is emptied to this point during a buffered read operation tape motion begins and data is read filling the empty portion of the buffer with new data from the tape For more information about the motion threshold see Section 3 2 12 32 510201 December 1991 12 MODE SELECT 15h Byte 05 Gap Threshold The Gap Threshold byte specifies the maximum number of consecutive gap blocks that the EXB 8500 will write on the current track while determining whether an empty buffer exists during a buffered write operation After writing the number of gap blocks specified by this byte the EXB 8500 will either continue the write operation if there is new data in the buffer or begin the process to stop tape motion if the buffer is still empty Before actually stopping tape motion the EXB 8500 writes additional gap bl
152. d that cannot be modified The value returned for this field is 0 Byte 03 Block Descriptor Length This byte contains the length of the Block Descriptor in bytes The EXB 8500 does not support multiple block descriptions The values for this byte are 00h and O8h 510201 13 MODE SENSE 13 3 Block Descriptor Non Page and Page Formats Bit Byte T 6 5 4 2 1 0 00 Density Code 01 MSB 02 03 Number of Blocks LSB 04 Reserved 05 MSB 06 07 Block Length LSB December 1991 Field Definitions The Block Descriptor is the same for both non page and page formats Byte 00 Density Code As described in Section 3 1 the EXB 8500 can read and write data in EXB 8500 format or in EXB 8200 format The Density Code field reported by the MODE SENSE command identifies the current operating density of the EXB 8500 As described in Table 13 5 on the next page the value reported for the Density Code field depends on the most recent activity that is the value reported for this field can be changed by loading a new tape or by issuing a MODE SELECT command a READ command or a WRITE command Notes m Refer to Section 12 12 on page 12 36 for examples for using the EXB 8500 to write read and append to EXB 8200 and EXB 8500 format tapes m The RTF field on the Vendor Unique Parameters Page 1 Page Code 20h indicates
153. de updates from a tape Part 2 includes Chapters 6 through 30 These chapters describe how the Small Computer System Interface SCSI is implemented in the EXB 8500 and provide details about the SCSI commands supported by the EXB 8500 To help you find the information you need quickly the commandis are listed in alphabetic order Appendix lists the cable requirements for the EXB 8500 Appendix B provides a sample application for using the EXB 8500 s directory support feature This option is available as a special EEPROM image 510201 1 General Information m Appendix C describes how the EXB 8500 autosizes tapes and lists the track and physical block counts for the different types and sizes of data cartridges supported by the EXB 8500 m Appendix D lists the possible combinations of values for the Additional Sense Code ASC and Additional Sense Code Qualifier ASCQ fields returned by the REQUEST SENSE 03h SCSI command The ASC and ASCQ values are listed in order for each sense key m Appendix E lists the Fault Symptom Codes that may be returned by the REQUEST SENSE 03h command These EXABYTE unique codes can be used to determine the specific nature of hardware and software errors and other events This appendix also describes the recommended recovery procedures for each Fault Symptom Code m A glossary index and reader s comment form are included at the back of this manual Intended Audience This manual is intended for
154. ded sense bytes which are defined as follows Byte 00 Bit 7 Valid This bit is set to 1 when the data in the Information bytes bytes 03 through 06 is valid for the command receiving the Check Condition status The value of the Information bytes is undefined when this bit is 0 Byte 00 Bits 6 through 0 Error Code A value of 70h for the Error Code field indicates that the sense data is associated with the command that received the Check Condition status A value of 71h for the Error Code field indicates that the sense data 15 for a deferred error condition and 15 associated with an earlier command Byte 01 Segment Number Byte 01 is always 0 Byte 02 Bit 7 FMK Filemark When set to 1 this bit indicates that the current command detected a filemark Byte 02 Bit 6 EOM End of Medium When set to 1 this bit indicates that the tape is at or past the early warning logical end of tape Byte 02 Bit 5 ILI Illegal Length Indicator When set to 1 this bit indicates that the logical block length requested did not match the actual logical block length of the data recorded on the tape Byte 02 Bit 4 RSVD This bit is reserved Byte 02 Bit 3 through 0 Sense Key The values contained in the Sense Key field are defined in Table 21 1 December 1991 21 3 21 REQUEST SENSE 03h Table 21 1 Sense Key Values Sense Key Meaning Explanation Oh No Sense Indicates that there is no specific sense key
155. detected the second time the message is received the EXB 8500 goes to the Bus Free phase by releasing the BSY signal 6 15 6 SCSI Physical Path Communications Initial Phase Message Out Transition to Message Out Does initiator own current process Abort process Go Bus Free Identify Is Disconnect bit Yes set Allow disconnects Disallow disconnects Continue processing No Operation Extended Message Go Bus Free Continue processing Execute warm reset Message Reject or Initiator Detected Error Set sense key to Aborted Command Bh Go to Status phase Send Check Condition Process Extended message Send Message Reject IN a Continue processing Figure 6 2 Message Out Bytes Received after Previous Message Out Phase 6 16 510201 6 SCSI Physical Path Communications Processing during the Command Out Phase Figure 6 3 shows how CDB bytes are processed Note that the Group Code in the CDB s first byte determines how many CDB bytes are to be transmitted If the initiator asserts the Attention signal during the Command In phase the EXB 8500 waits until all CDB bytes have been received and then goes to the Message Out phase Parity Error in Command Out Phase If a parity error is detected in the CDB byte being sent by the initiator the EXB 8500 goes to Message
156. disabled 24 1 24 SEND DIAGNOSTIC 1 24 1 Field Definitions Byte 01 Bit 4 PF Page Format The Page Format bit specifies the format of the parameter list for the SEND DIAGNOSTIC command The EXB 8500 does not support any pages so the valid value for this field is 0 Byte 01 Bits 2 through 0 SelfTest DevOfL UntOfL The SelfTest DevOfL Device Offline and UntOfL Unit Offline bits are used together to determine the test to be performed and the data to be returned to the initiator Refer to Table 24 1 for the valid combinations of these three bits Bytes 03 and 04 Parameter List Length The Parameter List Length field is used only when the MD bit byte 05 bit 7 is 1 If the MD bit is 0 the Parameter List Length field must be set to 0000 As shown in Table 24 1 if the MD bit is 1 and the SelfTest DevOfL and UntOfL bits are set to 000 the Parameter List Length field specifies the starting address for the memory dump Valid values for the memory dump starting address are 0000h to 97FFh Byte 05 Bit 7 MD Memory Dump This bit indicates if a memory dump is requested as follows 0 Memory dump not requested Memory dump requested If the MD bit is 1 the SelfTest DevOfL and UntOfL bits must be 000 Note If the MD bit is 1 and the SelfTest DevOfL and UntOfL bits are not 000 the SEND DIAGNOSTIC command is rejected with Check Condition status The sense key is set to Illegal Request 5h and
157. do not issue this command unless you are actually loading new microcode Be sure that the EXB 8500 is reserved for the initiator s exclusive use while the WRITE BUFFER command or command sequence is executing Do not send other SCSI commands such as TEST UNIT READY to the EXB 8500 while the WRITE BUFFER command or command sequence is executing Do not power off or reset the EXB 8500 while this command is executing If a reset hardware failure or power failure occurs during the execution of this command the EXB 8500 may not be able to operate If this occurs use the CTS Monitor program to reload microcode from a BIN file through a serial cable attached to the Monitor port See the Monitor User s Guide for the 8mm Cartridge Tape Subsystem for complete instructions Note If there is a tape in EXB 8500 it will be unloaded and ejected 29 2 510201 29 WRITE BUFFER 3Bh Time Required to Load Code with WRITE BUFFER As shown in Table 29 1 just over one minute is required to load new microcode from the SCSI bus using a single WRITE BUFFER command Note Slightly more time may be required to load new microcode using several WRITE BUFFER commands This increase in time is related to host overhead Table 29 1 Time Required to Load Code with WRITE BUFFER Command Step Time required seconds Transfer the data across the SCSI bus 4 Validate image in buffer 19 Load new code into flash EPROMs 16 Perform a p
158. ds the digital LBOT pattern and identifies it as a microcode update tape 2 The EXB 8500 reads the data on the tape into its buffer The amber LED will begin to flash slowly about 1 blink per second at this point December 1991 5 1 5 Loading New Microcode from Tape 3 The image in the buffer is validated This step ensures that the microcode to be loaded into the EXB 8500 is valid During validation the buffer image is checked for the following Correct header format Proper number of files Correct format for each line Each line of code bytes must have a proper address data type and checksum CRC match Hardware boot code support for new microcode version 4 After the data has been read into the buffer and validated the EXB 8500 unloads the tape but does not eject it the door is not opened Note If any of the validation steps fail the amber light will flash at a fast rate about 4 blinks per second Push the unload button to eject the tape and restore normal EXB 8500 operation then repeat the process with a new microcode update tape 5 The current contents of the EXB 8500 s program memories are erased and replaced with the validated microcode from the buffer CAUTION Do not power off or reset the EXB 8500 during this step Wait until step 6 completes The tape will be ejected when the load process is complete If a hardware or power failure occurs during this step the EXB 8500 may not
159. e location of errors in the MODE SELECT 15h command If one of the bytes sent with the MODE SELECT command contains an illegal value or if a reserved bit is set the EXB 8500 returns Check Condition status To determine which byte contains the error issue a REQUEST SENSE command The sense key will be set to Illegal Request 5h and the Fault Symptom Code field will indicate which of the consecutively received bytes is in error For example if the Block Descriptor Length field byte 03 in the Parameter List Header is invalid the value for the Fault Symptom Code byte would be 04h the first byte received is byte 1 not byte 0 Note that this use of the Fault Symptom Code byte applies to the MODE SELECT command only and is not described in Appendix E 21 10 510201 December 1991 21 REQUEST SENSE 03h Priorities of Sense Bytes Multiple errors can occur simultaneously in the EXB 8500 The sense key reflects the most catastrophic error of all those occurring simultaneously For example if a Medium Error and a SCSI bus parity error occur simultaneously the sense key will be set to Aborted Command for the SCSI bus parity error Sense Byte Pending Status When the EXB 8500 reports Check Condition status in response to a command from an initiator the EXB 8500 retains the sense byte pending status including error information and Check Condition status for the initiator until one of the following occurs m Error information is re
160. e number of gap blocks specified by this byte the EXB 8500 will either continue the write operation if there is new data in the buffer or begin the process to stop tape motion if the buffer is still empty Before actually stopping tape motion the EXB 8500 writes additional gap blocks to complete the current track and then writes one or two complete gap tracks See the EXB 8500 8mm Cartridge Tape Subsystem Product Specification for more information Values returned for the Gap Threshold byte range from 00h to 07h The default value is 07h 13 33 13 MODE SENSE 1Ah 13 10 Vendor Unique Parameters Page 2 Page Codez21h Bit 7 6 5 4 3 2 1 0 Byte 00 Reserved Page Code 01 Page Length 02 Reserved 03 Reserved WWR 04 Reserved 05 Reserved 13 34 Field Definitions The Vendor Unique Parameters Page 2 is returned only when the Page Code field in the CDB is set to 21h or Byte 00 Bits 5 through 0 Page Code The Page Code identifies the type of MODE SENSE page being transferred This is Vendor Unique Parameters Page 2 The value returned for the Page Code is 21h Byte 01 Page Length The Page Length indicates the number of bytes in the Vendor Unique Parameters Page 2 that follow this byte The value returned for this byte is 04h Byte 02 Byte 03 Bits 7 through 1 Reserved These bits and bytes are reserved Byte 03 Bit 0 WWR Wri
161. e EXB 8500 can disconnect from the initiator while the WRITE command is executing 28 1 Field Definitions Byte 01 Bit 0 Fixed The Fixed bit defines the type of write operation being performed as follows 0 A single logical block is written and the length of this block in bytes is specified in the Transfer Length field 1 One or more fixed length logical blocks are written and the number of blocks is specified in the Transfer Length field The length of each block is either the power on default block length or the length specified with the currently active MODE SELECT parameters bytes 5 through 7 of the Block Descriptor December 1991 28 1 28 WRITE 0Ah Note The EXB 8500 returns Check Condition status with the sense key set to Illegal Request 5h in the following cases m The Fixed field in the WRITE command is 0 variable length logical block and the Block Length field in the current MODE SELECT data is greater than 0 fixed length logical blocks m The Fixed field in the WRITE command is 1 fixed length logical blocks and the Block Length field in the current MODE SELECT data is 0 variable length logical block The ASC and ASCQ bits are set to 81h and 00h fixed variable mismatch Bytes 02 through 04 Transfer Length The Transfer Length field defines the amount of data to be written as follows When the Fixed bit is set to O variable length the Transfer Length field contains the length of t
162. e edge of the data cartridge as shown in Figure 3 2 If the red tab is visible the cartridge is write protected and cannot be written to or erased m To write enable the data cartridge move the write protect switch toward the edge of the data cartridge as shown in Figure 3 2 If the red tab is not visible the data cartridge is write enabled and can be written to or erased Figure 3 2 Write Protect Switch on EXATAPE 8mm Data Cartridge 3 14 510201 3 Operating the EXB 8500 3 7 Loading a Data Cartridge in the EXB 8500 To load a data cartridge into the EXB 8500 follow these steps 1 Ensure that the write protect switch has been set correctly for the desired operation See Section 3 6 If you have just powered on the EXB 8500 be sure that the green LED on the front panel is off indicating that the EXB 8500 is ready to load the data cartridge If necessary press the unload button to open the door on the EXB 8500 Insert the data cartridge into the EXB 8500 with the label side up and the write protect switch facing you Gently close the door The EXB 8500 automatically loads the data cartridge and presents ready status green LED on Note If you have disabled autoload with a MODE SELECT command the EXB 8500 will not go to the ready state until a LOAD 1Bh command has been executed Three options are available from EXABYTE to control how the EXB 8500 handles tape motion commands during the load operation Depend
163. e format D8h 5h 3 Overlapped commands attempted Bad ITL nexus D9h 5h 4 Logical block out of range DAh 5h 4 Illegal bit set in Identify message EOh Bh 3 The command was aborted in the CDB phase Parity or other error Eih Bh 3 The command was aborted before the Data phase Received bad message E2h Bh 11 The command was aborted the Data phase lInitiator Detected Error message E3h Bh 3 ma command was aborted in the Data phase Received bad message E4h Bh 3 The command was aborted after the Data phase Received bad message out E5h Bh 3 The command was aborted after the Data phase Other error E6h Bh 3 The WRITE command was aborted because of a SCSI bus parity error December 1991 E 5 Appendix E Fault Symptom Codes FSC SK ERP Description E7h Bh 11 The initiator sent an Abort or Initiator Detected Error message during a read operation and the command was aborted EBh Bh 3 A WRITE BUFFER command sequencing error occurred FAh 4h 15 The EXB 8500 s serial number is invalid or blank FCh 4h 15 Head sync value in EEPROM is out of range FDh 4h 15 The EEPROM contains meaningless information If the read back check criteria are not met for an LBOT filemark or EOD block written to tape the EXB 8500 moves the tape backward and retries the operation once If the read back check criteria are still not met the EXB 8500 returns Check Condition status and
164. e has occurred it remains in effect for all operations on the particular tape including the rewriting of LBOT For more information about how you can use this feature to change the tape format without issuing a MODE SELECT command refer to page 12 40 13 12 510201 December 1991 13 MODE SENSE Table 13 6 lists the possible values for the Density Code byte Table 13 6 Values for the Density Code Byte in MODE SENSE Command Density Code Tape Format Approximate Capacity ooh EXB 8500 format 5 0 GBytes 14h EXB 8200 format 2 5 GBytes 15h EXB 8500 format 5 0 GBytes 8 Approximate capacity based on a 112m EXATAPE P This Density Code is included to enable EXB 8500 drivers to be downwardly compatible with EXB 8200 drivers This field is reserved in EXB 8200 drivers For more information about using the MODE SELECT command to change the data format refer to Section 12 3 For more information about the differences between EXB 8500 format and EXB 8200 format refer to the 8500 6mm Cartridge Tape Subsystem Product Specification 13 13 13 MODE SENSE 13 14 Bytes 01 through 03 Number of Blocks The value for the Number of Blocks field indicates the total capacity of the tape in 1 KByte physical blocks LBOT to LEOT The value returned for this field depends on the setting of the Density Code if the Density Code is set for EXB 8500 format the Number of Blocks will be two times larger than if the Dens
165. e in the buffer during a buffered write operation the EXB 8500 reconnects to the initiator to accept additional data When the buffer fills to this level during a buffered read operation the EXB 8500 reconnects to the initiator and data 1s transferred Byte 04 Gap Threshold The Gap Threshold byte indicates the maximum number of consecutive gap blocks that the EXB 8500 will write on the current track while determining whether an empty buffer exists during a write operation After writing the number of gap blocks specified by this byte the EXB 8500 will either continue the write operation if there is new data in the buffer or begin the process to stop tape motion if the buffer is still empty Before actually stopping tape motion the EXB 8500 writes additional gap blocks to complete the current track and then writes one or two complete gap tracks See the EXB 8500 8mm Cartridge Tape Subsystem Product Specification for more information Values returned for the Gap Threshold byte range from 00h to 07h The default value is 07h 13 18 510201 13 MODE SENSE 13 5 Read Write Error Recovery Page Code 01h Bit 7 6 5 4 3 2 1 0 Byte 00 PS RSVD Page Code 01 Page Length 02 Reserved TB RSVD EER PER DIE DCR 03 Read Retry Count 04 Reserved 07 08 Write Retry Count Field Definitions The Read Write Error Recovery Page indicates
166. e initiator beginning with the next logical block Notes m For a read operation the EXB 8500 automatically sets itself to the data format used when the tape was written that is to either EXB 8500 format or EXB 8200 format m The EXB 8500 can read tapes that have a combination of fixed length and variable length data blocks m The EXB 8500 will report the early warning condition LEOT reached if the REW bit is set with the MODE SELECT command byte 8 bit 0 in the Device Configuration Page for PF 1 format m Ifthe disconnect option is enabled the EXB 8500 can disconnect from the initiator while the READ command is executing December 1991 15 1 15 READ 08h 15 1 Field Definitions 15 2 Byte 01 Bit 1 SILI The SILI Suppress Illegal Length Indication bit is used to suppress an illegal length Check Condition status for read operations that read logical blocks that do not contain the defined number of bytes This bit is valid only when the read operation is for variable length logical blocks that is when the Fixed bit Is set to 0 0 Do not suppress illegal length indication Check Condition status 1 Suppress illegal length indication Check Condition status Note Ifthe Fixed bit is 1 fixed length logical blocks and the SILI bit is 1 the EXB 8500 returns Check Condition status with the sense key set to Illegal Request 5h The ASC and ASCQ fields are set to 24h and 00h Byte 01 Bit 0 Fixed The Fixed
167. e initiator by entering the Reselection phase After completing the reselection the EXB 8500 will send an Identify message to the initiator to re establish the physical path 510201 6 SCSI Physical Path Communications 6 2 SCSI Bus Error Recovery Initiators Supporting Command Complete Message Only This section describes the actions to be taken by the initiator and the EXB 8500 when a SCSI bus parity error occurs The information in this section applies to those initiators that support the Command Complete message only Parity Error in Command Out Phase When parity checking is enabled and the EXB 8500 detects a parity error during the Command Out phase it immediately sends Check Condition status to the initiator followed by a Command Complete 00h message The sense key is set to Aborted Command Bh and the SCSI Bus Parity Error BPE bit is set to 1 The initiator should reissue the command Parity Error in Data Out Phase When parity checking is enabled and the EXB 8500 detects a parity error in the user data associated with the WRITE command it aborts the data transfer When this condition occurs the EXB 8500 immediately sends Check Condition status to the initiator followed by a Command Complete 00h message The sense key is set to Aborted Command Bh and the SCSI Bus Parity Error BPE bit is set to 1 The initiator may be able to recover by reissuing the WRITE command Parity Error in the Data In Phase If the parity
168. e name Four bytes of READ POSITION data for each data set on tape Note For best results use 1 KByte or smaller fixed length blocks to create the directory pad Eventually this directory pad will be overwritten by the master directory for the tape Appendix B 8500 Directory Support 2 Using additional filler data create a second pad after the directory pad The minimum size for the second pad is 12 MBytes This pad allows room for the erase head position and the EOD mark written when you rewind the tape after updating the master directory Note For best results use 1 KByte or smaller fixed length blocks to create the second pad 1BOT DIRECTORY PAD 12 MBYTE PAD 3 Write a long filemark after the 12 MByte pad This filemark provides a clear separation between the pad area and the data area LBOT DIRECTORY PAD 12 MBYTE PAD LFM 4 Issue a READ POSITION command to determine the EXB 8500 s current position This will be the starting location for the first file in the first data set DS 1 In the initiator s memory store the information returned for the First Block Location field bytes 04 through 07 of the READ POSITION data This information will be used later to update the directory for the data set DIR 1 1 Issue READ POSITION LBOT DIRECTORY PAD 12 MBYTE PAD LFM 2 Store First Block Location da
169. e specific command Bits 4 through 0 Command Code The Command Codes supported by the EXB 8500 are defined by the specific command Byte 01 Bits 7 through 5 Logical Unit Number LUN The LUN designates a specific unit within a group of devices associated with the target Since the EXB 8500 is a single device target and does not support multiple devices the LUN must be 0 All command definitions in this manual show this field containing 0 Byte 01 Bits 4 through 0 Vendor These bits are used as defined in the specific commands Bytes 02 through 05 Logical Block Address These bytes are used as defined in the specific commands Byte 06 Reserved This byte is reserved Bytes 07 and 08 Transfer Parameter List or Allocation Length These bytes contain the transfer length the parameter list length or the allocation length as required by the specific command 7 5 7 8500 SCSI Command Set Byte 09 Control Byte The Vendor Unique portion of the Control byte is defined for each specific command if used The EXB 8500 does not support linked commands or recognize the Flag bit The following are the field definitions for the Control byte Bits 7 and 6 Vendor Unique Command unique Bits 5 through 2 Reserved These bits are reserved Bit 1 Flag Not used must be 0 Bit 0 Link Not used must be 0 7 3 Command Format Errors 7 6 This section defines the errors that occur when the contents of the command d
170. earing the Unit Attention Condition The Unit Attention condition persists for each initiator until that initiator issues any command other than INQUIRY 12h or REQUEST SENSE 03h First Command Received after Unit Attention Occurs If the first command received after a Unit Attention condition occurs is an INQUIRY or REQUEST SENSE command the EXB 8500 executes the command reports any pending status and preserves the Unit Attention sense data If the first command received after a Unit Attention condition occurs is any other command the EXB 8500 does not execute the command and returns Check Condition status with the sense key set to Unit Attention 6h Next Command Received after Unit Attention Reported If the next command after the Unit Attention condition has been reported with Check Condition status is a REQUEST SENSE or an INQUIRY command the EXB 8500 executes the command and preserves the Unit Attention sense data If however the next command after the Unit Attention condition has been reported with Check Condition status is any other command then the command is executed and the Unit Attention sense data is cleared Note If multiple Unit Attention conditions occur before the initiator selects the EXB 8500 only the sense data for the latest Unit Attention condition is presented 510201 6 SCSI Physical Path Communications 6 5 Resetting the EXB 8500 The EXB 8500 can be reset by any of the following Powering the EXB
171. ection the procedure for performing the initial power on depends on whether the EXB 8500 has been stored If the EXB 8500 Has Been Stored for Less Than Six Months If the EXB 8500 has been stored for less than six months performing the initial power on involves the following step m Apply power to the EXB 8500 If the EXB 8500 is connected correctly both the amber and green LEDs will be lit After the power on initialization and self test have completed both LEDs will be turned off The EXB 8500 is now ready for normal operation If the EXB 8500 Has Been Stored for Six Months or More If the EXB 8500 has been stored for six months or more perform the following steps to ensure that the EXB 8500 s internal lubrication is properly distributed 1 Connect the EXB 8500 to a suitable test system through the SCSI interface 2 Apply power to the EXB 8500 If the EXB 8500 is connected correctly both the amber and green LEDs will be lit After the power on initialization and self test have completed both LEDs will be turned off This takes about 65 seconds 3 Press the unload button on the front of the EXB 8500 and insert a data cartridge 4 Push the door shut and wait while the EXB 8500 loads the tape and positions it at LBOT This takes about 50 seconds 5 Issue a WRITE command to write approximately 500 MBytes of data to the tape 6 Issue a REWIND command to rewind the tape to LBOT 7 Issue a READ command to read the data
172. ection Code ECC operation The counter is reset to 0 after any of the following m A REQUEST SENSE command is issued with the CLRCNT bit byte 05 bit 7 set to 1 Note that in order for the reset to be performed 29 1Dh bytes of sense data must be read by the REQUEST SENSE command m The tape is loaded or rewound m The mode changes from write to read or from read to write m The EXB 8500 is reset The counter does not roll over from FFFFFFh to 0 but remains at FFFFFh until reset Bytes 19 through 21 Unit Sense For each status bit defined in the Unit Sense bytes the normal or Good status is 0 When set to 1 these bytes indicate the condition defined for that bit as follows Note that the effective value for the RSVD bits is O Byte 19 Bit 7 PF Power Fail The EXB 8500 has been reset since the last status or the EXB 8500 has performed an internal reset due to power up Byte 19 Bit 6 BPE SCSI Bus Parity Error The EXB 8500 detected a SCSI bus parity error Byte 19 Bit 5 FPE Formatted Buffer Parity Error The EXB 8500 has detected an internal data buffer parity error Byte 19 Bit 4 ME Media Error In write mode this indicates a permanent write error In read mode this indicates an uncorrectable read error Byte 19 Bit 3 ECO Error Counter Overflow The Read Write Retry Counter byte 27 has overflowed to 0 Byte 19 Bit 2 TME Tape Motion Error The EXB 8500 has detected an error while attempting
173. eed search rewind four then O Servo error CRC fail Unrecoverable fault Failed power on self test Unload button fail Reset the EXB 8500 by pressing the unload button If this does not clear the error power the EXB 8500 off and back on again If the error occurs again the EXB 8500 needs service Power the EXB 8500 off and back on again If the error occurs again the EXB 8500 needs service 8 The EXB 8500 is performing power on self test diagnostics This takes less than 60 seconds P The green LED may go off before the amber LED if no tape is loaded The amber LED is on e when data transfer is occurring on the SCSI bus The amber LED is off o when data transfer is occurring The combination of on and off may appear as an irregular flash 4 CRC failures occur only within the first two seconds after a power on reset An unrecoverable fault can occur anytime during operation December 1991 3 13 3 Operating the EXB 8500 3 6 Setting the Write Protect Switch The EXATAPE 8mm data cartridge is equipped with a write protect switch to prevent the tape from being written to unintentionally Before loading a data cartridge in the EXB 8500 ensure that the write protect switch is set correctly for the desired operation You can use a ball point pen or similar instrument to set the write protect switch m Towrite protect the data cartridge move the write protect switch away from th
174. efault for PE is 1 Byte 02 Bit 0 NAL No Auto Load This bit indicates whether the automatic loading of the tape into the tape path is disabled when the data cartridge is inserted into the EXB 8500 0 Auto loading is enabled 1 Auto loading is disabled The power on default value for NAL is 0 Byte 03 Bits 7 through 5 RTF Read Tape Format These bits indicate the format of the data on the currently loaded data cartridge This is the format that the EXB 8500 will use when it reads the tape 000b The data on the tape is in EXB 8500 format or there is no data on the tape 001b The data on the tape is in EXB 8200 format For more information about using the MODE SELECT command to change the data format refer to Section 12 3 For more information about the differences between EXB 8500 format and EXB 8200 format refer to the 8500 6mm Cartridge Tape Subsystem Product Specification December 1991 13 31 13 MODE SENSE Byte 03 Bits 4 through 2 WTF Write Tape Format These bits indicate the format that will be used when the EXB 8500 writes data to the tape The value returned for these bits reflects the default density the density set with the most recent MODE SELECT command or the density of the data already on the tape 000b EXB 8500 format 001b EXB 8200 format For more information about using the MODE SELECT command to change the data format refer to Section 12 3 For more infor
175. emented Note Ifthe initiator sends a Message Reject message after a non message phase the EXB 8500 treats this as an error by the initiator and aborts any processes owned by the initiator To indicate its intention of sending this message the initiator must assert the Attention signal before releasing ACK for the REQ ACK handshake of the message that will be rejected When the EXB 8500 sends this message it changes to Message In phase and sends this message before requesting additional message bytes from the initiator This provides an interlock so that the initiator can determine which message is rejected December 1991 6 7 6 SCSI Physical Path Communications 6 8 No Operation 08h The initiator sends the No Operation message in response to the EXB 8500 s request for a message when the initiator does not currently have any other valid message to send Message Parity Error 09h The initiator sends the Message Parity Error message to the EXB 8500 to indicate that the last message it received had a parity error The EXB 8500 responds by re sending the previous message Note Ifthe EXB 8500 receives a Message Parity Error message when the last phase was not Message In it sends a Message Reject message to the initiator To indicate its intention of sending this message the initiator must assert the Attention signal before releasing ACK for the REQ ACK handshake of the message that has the parity error This provides an interlo
176. en the early warning condition LEOT is detected during a write operation This bit is set to 1 in the MODE SENSE data and is ignored by the MODE SELECT command Bytes 11 through 13 Buffer Size at Early Warning The Buffer Size at Early Warning is not supported by the EXB 8500 The value returned for this field is 0 Byte 14 Select Data Compression Algorithm The Select Data Compression Algorithm field is not supported by the EXB 8500 The value returned for this field is 0 510201 13 MODE SENSE 13 9 Vendor Unique Parameters Page 1 Page Codez20h Bit 7 6 5 4 3 2 1 0 Byte 00 PS RSVD Page Code 01 Page Length 02 CT RSVD ND RSVD NBE EBD PE NAL 03 RTF WTF RSVD P5 04 Motion Threshold 05 Gap Threshold December 1991 Field Definitions The Vendor Unique Parameters Page 1 is returned only when the Page Code field in the CDB is set to 20h or 3Fh Byte 00 Bit 7 PS The Parameters Savable bit indicates if the MODE SENSE parameter data contained in this page is savable The EXB 8500 does not support this feature The value returned for this bit is 0 Byte 00 Bits 5 through 0 Page Code The Page Code identifies the type of MODE SENSE data being transferred This is the Vendor Unique Parameters Page 1 The value returned for the Page Code is 20h Byte 01 Page Length The Page Length indicates the number of Vendor Unique Parameters Pa
177. ensity m A blank tape written before you issue the first MODE SELECT command will be written in the power on default format For more information about EXB 8500 format and EXB 8200 format refer to the EXB 8500 8mm Cartridge Tape Subsystem Product Specification For information about changing the power on default density refer to Section 3 4 510201 December 1991 12 MODE SELECT 15h Bytes 01 through 03 Number of Blocks The EXB 8500 determines the value for the Number of Blocks field when it loads a tape and then returns this value in the MODE SENSE data This field is ignored by the MODE SELECT command Bytes 05 through 07 Block Length The Block Length field defines the length in bytes of each logical block described by the Block Descriptor A value of 0 for the Block Length field indicates variable length logical blocks A value greater than O indicates fixed length logical blocks The power on default value for the block length is 400h 1 024 bytes The limit on the block length is the maximum block length specified by the Read Block Limits data see Section 16 2 That is if the ND bit is set to 0 the maximum block length is 03C000h or 240 KBytes if the ND bit is set to 1 the maximum block length is 28000h or 160 KBytes Notes m If you specify a value between 28001h and 03CO000h for the Block Length the EXB 8500 automatically sets the ND bit to 0 If however you specify a number greater than 03C000h for the
178. er List Header is the same for both non page and page formats Byte 02 Bits 6 through 4 Buffered Mode The EXB 8500 supports two data transfer modes as follows 000 Unbuffered mode 001 Buffered mode In buffered mode data from a WRITE command and filemarks from a WRITE FILEMARKS command EXB 8500 format only are held in the EXB 8500 s buffer until one of the following events causes the data and filemarks to be written to the tape m The motion threshold is reached m The EXB 8500 receives one of the following commands Ooooeeo REWIND 01h WRITE FILEMARKS 10h non immediate SPACE 11h in either direction ERASE 19h LOAD UNLOAD 1Bh LOCATE 2Bh in the reverse direction m The operator presses the unload button m Thetime specified for the Write Delay Time field elapses note however if the Write Delay Time field is 0 a partially full buffer is not flushed to tape Note December 1991 Section 12 8 for more information The Write Delay Time field can be set for page format only see 12 7 12 MODE SELECT 15h 12 8 In buffered mode status 1s returned when the last block of data has been transferred to the EXB 8500 s buffer In unbuffered mode status 1s returned only after the data has actually been written to the tape The power on default value for the Buffered Mode field is 001 Byte 02 Bits 3 through 0 Speed The EXB 8500 does not support any operations at different speeds
179. er could not read LBOT B6h Dh 11 EOT encountered during buffer flush COh eh 3 Unit Attention Power on reset occurred Cth 6h 3 Unit Attention Data cartridge may have been changed C2h 6h 3 Unit Attention MODE SELECT parameters were changed C3h 6h 3 Unit Attention New microcode was loaded C4h 6h 3 Unit Attention Operator requested media removal C6h 2h 7 Not Ready Cause not known E 4 510201 Appendix E Fault Symptom Codes FSC SK Description C7h 2h 3 Not Ready but becoming ready C8h 2h 2 3 oa command is required to move the tape from its current C9h 2h 7 The command requires a tape but no tape is loaded CCh 5h 4 Parameter List Length error in the MODE SELECT CDB CDh 5h 4 Illegal Op Code CEh 5h 4 Invalid field or reserved bits set in the CDB CFh 5h 4 The LUN is not supported DOh 5h 4 Invalid field in Parameter List MODE SELECT D1h 5h 4 The LUN in the Identify message is illegal not zero D2h 5h 11 Media removal is prevented D3h 5h 4 A variable fixed mismatch occurred between the CDB and the MODE SELECT parameters D4h 5h 4 Illegal transfer length in CDB D5h 5h 11 The command requires no tape but a tape is loaded SEND DIAGNOSTICS D6h 5h 11 Could not change the MODE SELECT parameters since the tape was not at LBOT D7h 5h 11 Cannot read the tape position Incompatibl
180. er is greater than or equal to the total transfer length specified by the CDB m During a read operation the data transfer to the initiator does not start until all of the data requested by the CDB up to a total transfer length of 160 KBytes is resident in the EXB 8500 s buffer m If the Buffer Full Ratio and the Buffer Empty Ratio are set to values less than AOh or greater than COh they will be changed to AOh This is necessary for proper buffer management Byte 02 Bit 4 RSVD This bit is reserved Byte 02 Bit 3 NBE No Busy Enable This bit is included for EXB 8200 compatibility only This bit is set to 1 in the MODE SENSE data and is ignored by the MODE SELECT command 510201 13 MODE SENSE Byte 02 Bit 2 EBD Even Byte Disconnect This bit indicates whether disconnects on even byte boundaries are enabled Two options are available from EXABYTE to control what happens when the EBD bit is set to 1 Depending on EXB 8500 s EEPROM image when the EBD bit is set to 1 disconnects can occur either on two byte boundaries or on four byte boundaries 0 Disconnect on any byte 1 Disconnect on even byte two byte or four byte boundaries Byte 02 Bit 1 PE Parity Enable This bit indicates whether parity checking on the SCSI bus is enabled When this bit is set to 1 every byte received by the EXB 8500 is checked for parity 0 Parity checking is disabled 1 Parity checking is enabled The power on d
181. error is detected in the user data associated with a READ command the initiator should do a backspace n blocks operation and set up to reread the blocks by reissuing the command If the parity error is detected during the execution of any other data command for example during sense operations it is only necessary to reissue the command If the command was REQUEST SENSE valid sense data will be returned because the sense data is not reset until the next non REQUEST SENSE or non INQUIRY command is issued December 1991 6 11 6 SCSI Physical Path Communications 6 3 Message Processing and SCSI Bus Error Recovery Initiators Supporting Additional Messages This section describes EXB 8500 message processing and SCSI bus error recovery for initiators supporting messages in addition to Command Complete It includes a number of charts showing the actions that the EXB 8500 will take in response to each message it receives from the initiator The charts are organized by phase transitions that is there is a chart for each possible initial phase with the transition to the Message Out phase The charts indicate the specific action the EXB 8500 will take for each type of message The text accompanying each chart also describes the actions to be taken by the initiator and the EXB 8500 when a SCSI bus parity error occurs EXB 8500 Response to the Attention Signal Once the physical path management mechanism has been established by the initiator u
182. es the length of the tape in use The method the EXB 8500 uses for autosizing depends on the length of the tape Shorter Tape Sizes If the tape is relatively short its length can be accurately determined by the EXB 8500 during the load operation Shorter tape sizes that can be reliably autosized at LBOT include the following P5 15 P5 30 P6 15 P6 30 P6 60 For these shorter length tapes the EXB 8500 ignores the settings of the CT and P5 bits in the MODE SELECT 15h command December 1991 C 1 Appendix C Data Cartridge Capacities Longer Tape Sizes If the tape is relatively longer its length cannot be accurately determined during the load operation Longer tape sizes that cannot be reliably autosized at LBOT include the following 5 60 5 90 6 90 6 120 For these longer length tapes the 8500 initially uses the settings of the CT and P5 bits in the MODE SELECT command to estimate the size of the data cartridge As shown in Table C 1 these bits can be set in various combinations to indicate the type of cartridge that is expected to be loaded in the EXB 8500 Table C 1 Combinations of CT and P5 Bits in MODE SELECT 15h Command Setting of CT bit Setting of P5 bit Expected cartridge type 0 0 P6 1 0 Unknown use 0 or 1 lee P5 f the expected data cartridge type is unknown that is if the data cartridge loaded in the EXB 8500 could be either a P5 or a P6 s
183. escriptor block CDB without parity error are invalid or because of double bit SCSI errors host programming errors or command implementation errors Illegal Operation Code If the Operation Code in the CDB is not supported by the EXB 8500 the command is terminated and Check Condition status is returned to the initiator The sense data is created as follows m The sense key is set to Illegal Request 5h m The Additional Sense Code is set to Illegal Operation Code 20h m The Additional Sense Code Qualifier is set to 0 Illegal Logical Unit Number If the Logical Unit Number in the CDB is not supported by the EXB 8500 the command is terminated and Check Condition status is returned to the initiator The sense data is created as follows m The sense key is set to Illegal Request 5h m The Additional Sense Code is set to Logical Unit Not Supported 25h m The Additional Sense Code Qualifier is set to O 510201 7 8500 SCSI Command Set Reserved Byte or Bits Non Zero If the bytes or bits in the Reserved field as defined by the ANSI SCSI 2 standard are not 0 the command 15 terminated and Check Condition status 15 returned to the initiator The sense data is created as follows m The sense key is set to Illegal Request 5h m The Additional Sense Code is set to Invalid Field in CDB 24h m The Additional Sense Code Qualifier is set to O Control Byte or Bits Set Incorrectly If the Link or Flag fields bits 1
184. et the CT bit to 1 and the P5 bit to 0 In this case the EXB 8500 will use the international equivalency mode PI to size the data cartridge The PI mode uses the smaller of two comparable P5 and P6 data cartridge sizes When set to 1 the P5 bit overrides the CT bit C 2 510201 Appendix C Data Cartridge Capacities Using the settings of the CT and P5 bits in conjunction with its initial determinations of tape length the EXB 8500 estimates the data cartridge type and size as shown in Table C 2 Table C 2 Initial Autosizing Estimates Made by the EXB 8500 Type of cartridge 5 5 Cartridge initially actually loaded Setting of CT bit Setting of P5 bit sredah 0 0 P6 90 P5 60 or 1 0 P5 60 P6 90 0 or 1 1 5 60 0 0 6 120 5 90 or 1 0 P6 120 P6 120 0 or 1 1 5 90 When the CT bit is 1 and the P5 bit is 0 the EXB 8500 uses the PI mode In this case P5 60 is the smaller of the two comparable data cartridges P6 120 is the smaller of the two comparable data cartridges Then as the tape position approaches LEOT the EXB 8500 accurately resizes these longer length tapes If the CT and P5 bits are incorrectly set for the type of cartridge loaded the EXB 8500 may increase or decrease the estimated block count when it resizes the tape This ensures that LEOT is always detected correctly and prevents tape capacity errors December 1991 C
185. etected during locate 11 4 detected during read 15 4 detected during space 25 4 detected during verify 27 3 spacingto 25 5 equipment for installation 2 1 ERASE 19h command 8 1 8 4 ERP See error recovery procedures error recovery See SCSI bus error recovery error recovery procedures E 7 errors CDB format 7 6 even byte disconnect MODE SELECT command 12 14 12 31 MODE SENSE command 13 16 13 31 EXABYTE 9h sense key D 6 examples directory support B 1 B 10 writing and reading EXB 8200 format 12 36 writing and reading EXB 8500 format 12 38 EXATAPE capacities of 8 See also data cartridges EXB 8200 compatibility with EXB 8500 3 2 EXB 8200 format appending to 12 37 compared to EXB 8500 format 3 3 filemarks 3 5 logical block structure 3 4 physical block structure 3 4 reading 12 38 track structure 3 4 writing 12 37 EXB 8200SX compatibility with EXB 8500 3 2 EXB 8205 compatibility with EXB 8500 3 2 EXB 8500 agency standards for 1 6 cleaning 4 1 compatibility with other products 3 2 configuration options for 3 11 controls and indicators on 3 12 general description of 1 3 1 8 installing 2 1 2 14 loading data cartridges in 3 15 operating 3 1 3 22 510201 EXB 8500 continued packing 4 3 physical path communications 6 3 6 42 resetting 6 40 SCSI commands supported by 7 1 serial number for 9 8 shipping 4 3 unpacking 2 2 EXB 8500 format appending to 12 39 compared to EXB 8
186. event condition m The EXB 8500 is reset by a Bus Device Reset message SCSI bus reset or power on reset Byte 05 Bits 7 and 6 Vendor Unique There are no vendor unique definitions for this command December 1991 14 1 14 PREVENT ALLOW MEDIUM REMOVAL 14 2 Effect of Prevent Bit on Unload Button When the Prevent bit is set to 1 the unload button on the EXB 8500 is disabled pressing this button does not cause the tape to be rewound or ejected Note If the EXB 8500 s EEPROM image includes the super fast unload button setting pressing the unload button overrides the Prevent bit That is the EXB 8500 will eject the tape whether or not media removal has been prevented with the PREVENT ALLOW MEDIUM REMOVAL command Refer to Section 3 8 for more information Effect of Prevent Bit on UNLOAD 1Bh Command When the Prevent bit is set to 1 issuing an UNLOAD 1Bh command causes the data cartridge to be unloaded but not ejected from the EXB 8500 If there is data in the write buffer the data is written to tape Then the tape is rewound to PBOT and unloaded from the tape path 510201 15 READ 08h Bit 7 6 5 4 3 2 1 0 Byte 00 0 0 0 0 1 0 0 0 01 Logical Unit Number Reserved SILI Fixed 02 MSB 03 Transfer Length 04 LSB 05 Vendor Unique Reserved 0 0 The READ command transfers one or more bytes or blocks of data from the EXB 8500 to th
187. except INQUIRY and REQUEST SENSE receive Check Condition with the sense key set to Not Ready 2h For information about clearing a Unit Attention condition see Section 6 4 Effect of PREVENT ALLOW MEDIUM REMOVAL Command If an initiator has issued a PREVENT MEDIUM REMOVAL 1Eh command to prevent the removal of the data cartridge the door on the EXB 8500 will not open until that initiator sends an ALLOW MEDIUM REMOVAL command to allow the data cartridge to be removed If more than one initiator has issued PREVENT MEDIUM REMOVAL commands to the EXB 8500 to prevent the removal of the data cartridge the EXB 8500 s door will not open until each of those same initiators sends an ALLOW MEDIUM REMOVAL command to release the condition Note Ifthe EXB 8500 s EEPROM image includes the super fast unload button setting the EXB 8500 will eject the tape whether or not media removal has been prevented with the PREVENT ALLOW MEDIUM REMOVAL command For information about using the PREVENT ALLOW MEDIUM REMOVAL command see Chapter 14 Error During Unload Procedure If an error exists before or during the unload procedure the unload sequence will be suspended and the amber LED will flash If the unload button is pressed again the unload sequence will be reattempted however unwritten data in the buffer will not be written to tape The buffer and errors will be cleared Note Ifthe EXB 8500 s EEPROM image includes the super fast unload b
188. ffer m If the Reconnect Threshold byte is set to values less than AOh greater than COh it will be changed to AOh This is necessary for proper buffer management Byte 00 Bit 4 RSVD This bit is reserved Byte 00 Bit 3 NBE No Busy Enable This bit is included for EXB 8200 compatibility only This bit is set to 1 in the MODE SENSE data and is ignored by the MODE SELECT command Byte 00 Bit 2 EBD Even Byte Disconnect This bit indicates whether disconnects on even byte boundaries are enabled Two options are available from EXABYTE to control what happens when the EBD bit is set to 1 Depending on EXB 8500 s EEPROM image when the EBD bit is set to 1 disconnects can occur either on two byte boundaries or on four byte boundaries 0 Disconnect on any byte 1 Disconnect on even byte two byte or four byte boundaries 13 16 510201 13 MODE SENSE Byte 00 Bit 1 PE Parity Enable This bit indicates whether parity checking on the SCSI bus is enabled When this bit is set to 1 every byte received by the EXB 8500 is checked for parity 0 Parity checking is disabled 1 Parity checking is enabled The power on default for PE is 1 Byte 00 Bit 0 NAL No Auto Load This bit indicates whether the automatic loading of the tape into the tape path is disabled when a data cartridge is inserted into the EXB 8500 0 Auto loading is enabled 1 Auto loading is disabled The power on default value
189. fields and do not support EXB 8500 high speed search In addition the EXB 8500 does not support the 82005 high speed search feature Filemarks Like the EXB 8200 and the 82005 the EXB 8500 supports both short and long filemarks However the sizes of these filemarks are different in EXB 8500 format than they are in EXB 8200 format m Thelong filemark in EXB 8500 format occupies 48 KBytes of space and allows data to be appended to it m The short filemark in EXB 8500 format occupies 1 KByte of space but does not allow data to be appended to it 3 5 3 Operating the 8500 As described in Table 3 2 the size of the filemarks that can be written depend on the format of the tape and on the setting of the Short bit in the WRITE FILEMARKS 10h command see Chapter 30 Table 3 2 Type and Size of Filemarks Type and Size of Filemarks Tape Long Short Written By Short bit 0 Short bit 1 KBytes Hex KBytes Hex EXB 8500 in EXB 8500 format e i 00h EXB 8500 in EXB 8200 format 2 160 21C000h 184 2E000h EXB 8200 2 160 21C000h 480 78000h 82005 2 160 21C000h 184 2E000h The short filemark written by the EXB 8500 in EXB 8200 format is equivalent to the short filemark written by the 82005 End of Data EOD When writing data in EXB 8500 format the EXB 8500 writes an end of data EOD mark to indicate the location of the la
190. fies the maximum number of consecutive gap blocks that the EXB 8500 will write on the current track while determining whether an empty buffer exists during a write operation After writing the number of gap blocks specified by this byte the EXB 8500 will either continue the write operation if there is new data in the buffer or begin the process to stop tape motion if the buffer is still empty Before actually stopping tape motion the EXB 8500 writes additional gap blocks to complete the current track and then writes one or two complete gap tracks See the EXB 8500 8mm Cartridge Tape Subsystem Product Specification for more information The Gap Threshold byte should be changed only when the average data transfer rate is slow and is impacting the capacity of the tape by forcing excessive start stop activity The Gap Threshold byte should be used in combination with the motion and reconnect thresholds described in this section Valid values for the Gap Threshold byte are 00h to FFh Any value greater than 07h is treated as 07h by the EXB 8500 The default value for the Gap Threshold byte is 07h 12 16 510201 12 MODE SELECT 15h 12 5 Read Write Error Recovery Page Page Code 01h Page Format Bit 7 6 5 4 3 2 1 0 Byte 00 Reserved Page Code 01 Page Length 02 Reserved TB RSVD EER PER DTE DCR 03 Read Retry Count 04 Reserved 07 08 Write Retry Count
191. for NAL is 0 Byte 01 Bits 7 through 1 Reserved These bits are reserved Byte 01 Bit 0 P5 This bit is set to 1 to indicate that the data cartridge expected by the EXB 8500 is a P5 European data cartridge When set to 1 this bit overrides the CT bit See Appendix C for information about data cartridge capacities and for an explanation of how the EXB 8500 autosizes data cartridges Byte 02 Motion Threshold The value in the Motion Threshold byte indicates the amount of data that must be in the buffer before tape motion is started for a buffered write or read operation The value is expressed in 4 KByte increments The default is 80h 512 KBytes Values range from 20h to DOh 128 to 832 KBytes When the buffer is filled to this point during a buffered write operation tape motion begins and data is written to the tape When the buffer is emptied to this point during a buffered read operation tape motion begins and data is read filling the empty portion of the buffer with new data from the tape December 1991 13 17 13 MODE SENSE Byte 03 Reconnect Threshold The value in the Reconnect Threshold byte indicates the amount of data that must be in the buffer before the EXB 8500 reconnects to the initiator for a buffered write or read operation The value is expressed in 4 KByte increments The default is 80h 512 KBytes Values range from 20h to DOh 128 to 832 KBytes When this amount of free space is availabl
192. format exceptions and error conditions 12 35 Fault Symptom Codes used to detect errors field definitions for CDB 12 1 Parameter List Header 12 7 parameter list length non page format parameter list length page format 12 4 PF field 12 1 12 24 12 19 12 35 12 2 MODE SELECT 15h command continued Read Write Error Recovery Page page format 12 17 Vendor Unique Parameters Page 1 Vendor Unique Parameters Page 2 page format 12 34 vendor unique parameters Non Page Format WWR bit 12 34 MODE SENSE 1Ah command allocation length non page format allocation length page format 13 5 Block Descriptor 13 11 Density Code field 13 11 Device Configuration Page page format Disconnect Reconnect Page 13 21 field definitions for CDB 13 2 non page format 13 1 page codes for 13 3 page format 13 2 Parameter List Header 13 8 Read Write Error Recovery Page RTF field 13 31 Vendor Unique Parameters Page 1 Vendor Unique Parameters Page 2 vendor unique parameters non page format WTF field 13 32 WWR bit 13 34 motion threshold described 3 7 setting with MODE SELECT non page format 12 15 setting with MODE SELECT page format 12 32 setting with Write Buffer Full and Read Buffer Empty Ratios 12 26 summary of 3 9 mounting requirements 2 7 N 12 29 12 12 13 4 13 25 13 19 13 29 13 34 13 15 No Operation 08h message 6 8 No Sense 0h sense key D 2 non page format MODE SENSE command normal unload opt
193. fter LBOT 15 reached default m If there is data in the buffer because an earlier WRITE 0Ah command was terminated with Check Condition status that data is discarded before the tape is rewound December 1991 23 1 23 REWIND 01h 23 1 Field Definitions 23 2 Byte 01 Bit 0 Immed The Immed bit is used to determine when command status is returned to the initiator as follows 0 Status is reported to the initiator when the REWIND command is completed 1 Status is reported to the initiator when the REWIND command is initiated by the EXB 8500 If the EXB 8500 buffer contains data from a previous WRITE command the EXB 8500 disconnects from the initiator 1f disconnect was enabled by the Identify message and writes the data in the buffer to the tape m Ifthe Immed bit is set to 1 the EXB 8500 reconnects to the initiator when the write operation has completed successfully It then returns Good status and performs the rewind operation Note Completing the write operation includes emptying the buffer to tape and writing the EOD mark EXB 8500 format tapes only This can take up to 12 seconds m If the Immed bit is set to 0 the EXB 8500 reconnects and returns status when the rewind operation is complete Byte 05 Bit 7 and 6 Vendor Unique There are no vendor unique definitions for this command 510201 24 SEND DIAGNOSTIC 1Dh Bit 7 6 5 4 3 2 1 0 By
194. fter writing the number of gap blocks specified by this byte the EXB 8500 will either continue the write operation if there is new data in the buffer or begin the process to stop tape motion if the buffer is still empty Before actually stopping tape motion the EXB 8500 writes additional gap blocks to complete the current track and then writes one or two complete gap tracks See the EXB 8500 8mm Cartridge Tape Subsystem Product Specification for more information The Gap Threshold byte should be changed only when the average data transfer rate is slow and is impacting the capacity of the tape by forcing excessive start stop activity The Gap Threshold byte should be used in combination with the motion and reconnect thresholds described in this section Valid values for the Gap Threshold byte are 00h to FFh Any value greater than 07h is treated as 07h by the EXB 8500 The default value for the Gap Threshold byte is 07h Note The Gap Threshold in the Device Configuration Page has the same function as the Gap Threshold in the Vendor Unique Parameters Page 1 If both pages are sent the value that is received last by the EXB 8500 takes precedence 12 25 12 MODE SELECT 15h 12 26 Byte 03 Active Partition The Active Partition byte is not supported by the EXB 8500 The valid value for this byte is 0 Byte 04 Write Buffer Full Ratio The Write Buffer Full Ratio represents the amount of data that must be present in the buffe
195. gal bit set in Identify message DAh 4Eh 00h Overlapped commands attempted Bad ITL nexus D8h 50h 01h Write append position error B 53h 02h Media removal prevented D2h 81h 00h Mode mismatch Fixed variable D3h The command requires no tape but a tape is loaded SEND oah 00h DIAGNOSTICS d 84h 00h Could not change the MODE SELECT parameters since the tape D6h was not at LBOT December 1991 D 5 Appendix D Sense Key Information Sense Key 6h Unit Attention ASC ASCQ Related Byte 12 Byte 13 Eee FSC 28h 00h A new tape load has occurred and the media may have been Cth changed 29h 00h reset SCSI bus reset or device reset has occurred COh 2Ah 01h MODE SELECT parameters have been changed C2h 3Fh Oih New microcode firmware was loaded C3h 5Ah Oih Operator requested media removal C4h Sense Key 7h Data Protect ASC ASCQ Related Byte 12 Byte 13 Explanation FSC 27h 00h The tape is write protected ur Sense Key 8h Blank Check ASC ASCQ Related Byte 12 Byte 13 Explananon FSC 00h 05h End of data encountered on a read operation 9 5 ASCQ Related Byte 12 Byte 13 Explanation FSC 15h 02h Positioning error detected by read of medium during a space or 15h 3Ah locate operation D 6 510201
196. ge 1 bytes that follow this byte The value returned for this byte is 04h Byte 02 Bit 7 CT Cartridge Type This bit reports what type of cartridge is expected to be loaded in the EXB 8500 0 P6 Cartridge Type Domestic 1 PI Cartridge Type International P5 P6 LEOT equivalency See Appendix C for information about data cartridge capacities and for an explanation of how the EXB 8500 autosizes data cartridges 13 29 13 MODE SENSE 13 30 Byte 02 Bit 5 ND No Disconnect During Data Transfer This bit indicates whether the EXB 8500 can disconnect from the initiator during the data transfer phase 0 The EXB 8500 can disconnect from the initiator during the data transfer phase The EXB 8500 will not disconnect during the data transfer phase The power on default for ND is 0 Restrictions when the ND bit is 0 m The maximum logical block size allowed in fixed or variable mode is 240 KBytes 3C000h Restrictions when the ND bit is 1 m The maximum logical block size in fixed or variable mode is 160 KBytes 28000h m The total number of bytes that can be transferred as a result of a single WRITE or READ command in fixed or variable mode is 160 KBytes 28000h That is the total transfer length specified by the CDB must be 160 KBytes or less m During a write operation the data transfer from the initiator does not start until the number of bytes of available space in the EXB 8500 s buff
197. ge Code 21h 6 bytes 06h Examples To transfer the Parameter List Header the Block Descriptor and the Vendor Unique Parameters Page 1 1 Specify 12h for the Parameter List Length byte 04h for the Parameter List Header 08h for the Block Descriptor 06h for the Vendor Unique Parameters Page 1 2 Set the Block Descriptor Length byte in the Parameter List Header to 08h 510201 December 1991 12 MODE SELECT 15h To transfer the Parameter List Header and the Read Write Error Recovery page 1 Specify ODh for the Parameter List Length byte 04h 09h 2 Set the Block Descriptor Length byte in the Parameter List Header to Table 12 3 summarizes the values you should designate for the Parameter List Length byte when you want to transfer the Parameter List Header the Block Descriptor and only one of the parameter pages You can use this table as a quick reference when you are interested in changing the parameters for only one of the MODE SELECT pages Table 12 3 Values to Designate for Parameter List Length Page Format Designate this For this page plus the Parameter List Header and Block amount Descriptor 15h Read Write Error Recovery Page Code 01h 18h Disconnect Reconnect Page Page Code 02h 1Ch Data Compression Page Page Code 0Fh 1Bh Device Configuration Page Page Code 10h 12h Vendor Unique Parameters Page 1 Page Code 20h 12h Vendor
198. ggested actions for each ERP code refer to EXB 8500 Error Recovery Procedures on page E 7 Important The Fault Symptom Codes may change as new revisions of the EXB 8500 firmware become available For this reason be sure to check the documentation provided with new firmware releases for the most current list of codes December 1991 E 1 Appendix E Fault Symptom Codes Table E 1 Fault Symptom Codes FSC SK ERP Description 02h 5h 11 A WRITE command was received when the tape was not at a legal position to write 03h 7h 5 A WRITE command was received when the data cartridge was write protected 04h Oh 11 LEOT was encountered during the current write operation the command may have terminated early 05h Bh 11 The write operation was aborted as requested 06h Oh 10 LEOT was encountered during the last write operation the command completed successfully 09h Oh 11 LEOT was encountered during a read operation OAh Oh 11 The actual block size read did not match the requested block size during a read operation OBh 3h 13 An uncorrectable block was encountered during a read operation OCh 8h 11 EOD was encountered during a read operation ODh Oh 11 A filemark was encountered during a read operation The EXB 8500 was not in a legal condition to read in write mode or not OEh 5h 11 ready OFh 8h 3 Already at blank tape so it is an er
199. grade Command descriptor block Centimeter 0 3937 inches The establishment of communications between the initiator and the selected target Cyclic redundancy check Canadian Standards Association The termination of communications between the initiator and the target During a disconnect the target releases control of the SCSI bus allowing the bus to become free The logical end of tape LEOT Error correction code Electrically erasable programmable read only memory Erasable programmable read only memory End of data End of medium End of tape G 1 Glossary EXB 8200 The EXB 8200 8mm Cartridge Tape Subsystem The EXB 8200 can store up to 2 5 gigabytes of data on a single 8mm data cartridge EXB 8200 format One of two data formats written and read by the EXB 8500 Tapes written by the EXB 8500 in EXB 8200 format can be read by any EXB 8200 82005 EXB 8500 EXB 8500c or EXB 8205 See also EXB 8500 format 82005 The 82005 8mm Cartridge Tape Subsystem The 82005 is very similar to the EXB 8200 but offers a high speed search capability EXB 8205 The EXB 8205 8mm Cartridge Tape Subsystem The EXB 8205 is a half high 8mm cartridge tape subsystem that can compress logical blocks of user data Assuming an average 2 1 compression ratio the EXB 8205 can store 5 0 gigabytes of data on a single 8mm data cartridge EXB 8500 The EXB 8500 8mm Cartridge Tape Subsystem The EXB
200. h is greater than the actual length the Information bytes are positive m If the requested length is less than the actual length the Information bytes are negative 2s complement notation When the READ command terminates in variable mode the tape is positioned after the block with the incorrect length at the start of the next logical block Fixed Length Mode If the Fixed bit is set to 1 and the actual length of any one block does not match the requested block length the EXB 8500 transfers the number of blocks requested until it encounters the block with the incorrect length Then the EXB 8500 terminates the READ command and returns Check Condition status The Illegal Length Indicator ILI bit and the Valid bit are set in the extended sense data with the sense key set to No Sense The Information bytes indicate the number of blocks not transferred to the initiator including the block with the incorrect length When the READ command terminates in fixed mode the tape is positioned after the block with the incorrect length at the start of the next logical block 510201 15 READ 08h Illegal Requests The following conditions cause the EXB 8500 to return Check Condition status with the sense key set to Illegal Request 5h m Therequested block length is greater than 240 KBytes or 160 KBytes if the ND bit is set m The Fixed bit is set to 0 and the block length in the MODE SELECT command is not 0 m The Fixed bit is
201. hange the format repeat steps 1 through 6 with a tape written in the new format Or load a blank tape to write in the EXB 8500 s power on default format 12 40 510201 13 MODE SENSE 1 Bit 7 6 5 4 3 2 1 0 Byte 00 0 0 0 1 1 0 1 0 01 Logical Unit Number RSVD DBD Reserved 02 PC Page Code 03 Reserved 04 Allocation Length 05 Vendor Unique Reserved 0 0 December 1991 The MODE SENSE command enables the EXB 8500 to report medium logical unit or device parameters to the initiator These values apply to all initiators in a multi initiator environment Depending on the value specified for the Page Code field the EXB 8500 can return these parameters in either of two formats non page format or page format Non Page Format In non page format the MODE SENSE parameters after the Block Descriptor are vendor unique This format is the same as that defined for the EXB 8200 that is SCSI 1 format It is equivalent to non page format for the MODE SELECT parameters In non page format the MODE SENSE parameters are returned in the following order 1 Parameter List Header 4 bytes 2 Block Descriptor 8 bytes optional 3 One to five bytes of vendor unique parameters 13 1 13 MODE SENSE Page Format In page format the MODE SENSE parameters after the Block Descriptor are structured as pages of related parameters This format is equivalent
202. hapter 25 Chapter 9 Chapter 27 Chapter 12 Chapter 22 Chapter 20 Chapter 8 Chapter 13 Chapter 10 Chapter 19 Chapter 24 Chapter 14 Chapter 11 Chapter 18 Chapter 29 Chapter 17 reference the command name and the operation code OP code are included in the header at the top of each page December 1991 7 1 7 8500 SCSI Command Set Sections 7 1 7 2 7 3 and 7 4 present basic information about command format field definitions command errors and command status This information is not repeated in the command descriptions The word Reserved or RSVD as used in field definitions for SCSI commands has one of the following meanings m Fields defined by in the ANSI Small Computer System Interface 2 SCSI 2 standard These fields are checked for a value of 0 If zeros are not present Check Condition status is returned with the sense key set to Illegal Request 5h m EXABYTE undefined fields These fields are reserved for future enhancements and are not currently checked for illegal values 7 1 Command Format The SCSI command formats for the six and ten byte commands are shown in the ANSI Small Computer System Interface 2 SCSI 2 standard The commands for the EXB 8500 are implemented according to this standard The following are the formats for the six and ten byte command descriptor blocks followed by the format of the Operation Code and the typical format for the Control byte Command Descriptor Bloc
203. hat there is no limit to the amount of time that the EXB 8500 can assert a BSY signal without a REQ ACK handshake Bytes 06 and 07 Disconnect Time Limit The disconnect time limit is determined by the minimum time it takes the EXB 8500 to disconnect from the SCSI bus and then initiate a reselection sequence The minimum disconnect time for the EXB 8500 is 265 usec This field cannot be changed by the initiator so the value returned for this field is 0 Bytes 08 and 09 Connect Time Limit The value returned for the Connect Time Limit is 0 The EXB 8500 uses 0 as a default value meaning that it disconnects from the bus after the amount of data defined by Maximum Burst Size has been transferred Bytes 10 and 11 Maximum Burst Size The Maximum Burst Size defines the amount of data to be transferred before disconnecting The value is expressed in increments of 512 bytes A value of 0 indicates that there 15 no limit on the amount of data transferred before disconnecting The EXB 8500 supports all values for this field The default value is 0 which means that disconnects and reconnects are performed using the value specified by the Buffer Full and Buffer Empty Ratios 13 22 510201 13 7 Data Compression Page CodezOFh 13 MODE SENSE 1Ah Bit 7 6 4 3 2 0 Byte 00 PS RSVD Page Code 01 Page Length 02 DCE DCC Reserved 03 DDE RED Reserved 04 MSB Compression Algorithm 0
204. he logical block in bytes The logical block can be any size from 0 to 240 KBytes Note Ifthe No Disconnect During Data Transfer ND bit is set the logical block can be any size from 0 to 160 KBytes See Chapter 12 for more information When the Fixed bit is set to 1 fixed length the Transfer Length field contains the number of logical blocks to be written The block length is the length specified with the MODE SELECT command The allowable block sizes are defined by the READ BLOCK LIMITS 05h command Note When the value for the Transfer Length field is 0 no data is transferred and the current position of the EXB 8500 is not changed Byte 05 Bits 7 and 6 Vendor Unique There are no vendor unique definitions for this command 28 2 510201 28 WRITE 0Ah 28 2 Tape Positioning December 1991 This section describes the legal tape positions for a write operation Tape Positioned at LBOT When writing to tape positioned at LBOT in EXB 8500 or EXB 8200 format the EXB 8500 automatically writes a new LBOT pattern and then writes the data from the buffer The data is written in the power on default density or in the density specified with the currently active MODE SELECT command Appending Data EXB 8500 Format Tapes When writing to tape in EXB 8500 format the EXB 8500 can append new data to existing data if the tape is positioned at any of the following locations m The beginning BOT side of a long filemark m The e
205. he optional EXB 8500 directory support feature m Chapter 12 MODE SELECT command reorganized to match the organization of Chapter 13 MODE SENSE command m Section 12 12 added to the MODE SELECT chapter This new section provides step by step instructions for writing reading and appending to tapes in EXB 8500 and EXB 8200 format a MODE SELECT 15h and MODE SENSE 1Ah commands revised to allow compatibility with SCSI drivers supporting data compression m New Vendor Unique Parameters Page 2 added to the MODE SELECT and MODE SENSE commands 510201 m New Chapter 17 describing the READ BUFFER 3Ch command m Clarified description of the RECEIVE DIAGNOSTIC RESULTS 1Ch command in Chapter 19 m New status bits RRR CLND and CLN added to the information returned by the REQUEST SENSE 03h command Chapter 21 m ADE bit added to the SPACE 11h command Chapter 25 for the optional EXB 8500 directory support feature m Revised Section 28 4 explaining what happens if the EXB 8500 encounters LEOT during a write operation m New Appendix B describing a sample application for the optional EXB 8500 directory support feature m Revised Appendixes D and E Appendix E now includes recommended error recovery procedures for each Fault Symptom Code December 1991 vi 510201 Contents Part 1 Installing and Operating the EXB 8500 1 1 1 General Information cres 1 3 1 1 About the EXB 8500 4
206. hen the ERASE command is initiated by the EXB 8500 If the buffer contains data from a previous WRITE command the EXB 8500 disconnects from the SCSI bus if disconnect was enabled by the Identify message and writes the data in the buffer to the tape m If the Immed bit is set to 1 the EXB 8500 to the initiator when the write operation has been completed successfully It then returns Good status and performs the erase operation Note Completing the write operation includes emptying the buffer to tape and writing the EOD mark EXB 8500 format tapes only This can take up to 12 seconds m If the Immed bit is set to 0 the EXB 8500 reconnects and returns status when the erase and rewind operations are complete Byte 01 Bit 0 Long The Long bit determines the amount of the tape to be erased as follows 0 The command is accepted but no erase operation is performed 1 All tape will be erased from the current position to PEOT Byte 05 Bits 7 and 6 Vendor Unique There are no vendor unique definitions for this command 510201 8 ERASE 19h 8 2 Tape Positioning This section describes the legal tape positions for an erase operation EXB 8500 Format Tapes For a tape written in EXB 8500 format a legal position for an erase operation is the tape positioned at any one of the following locations m LBOT m EOD mark m Either side of a long filemark Note Ifan EOD mark is not already present one will be
207. hreshold Elements set aside for future standardization Small Computer System Interface A unique identifier assigned to each device or subsystem on the SCSI bus Also referred to as the address Driving a signal to the true state Driving a signal to the false state or biasing the signal by the cable terminators to the false state When a signal is not driven by a bus but is biased by the cable terminators to the false state Information sent from the target to the initiator upon completion of a command A bus device usually a controller that performs an operation requested by an initiator The EXB 8500 is a target Micrometer 0 00003937 inches Microsecond 510201 Index A Abort 06h message 6 7 Aborted Command Bh sense key D 7 Additional Sense Code See ASC field Additional Sense Code Qualifier See ASCQ field allocation length INQUIRY 9 2 MODE SENSE non page format 13 4 MODE SENSE page format 13 5 RECEIVE DIAGNOSTIC RESULTS 19 2 REQUEST SENSE 21 1 appending to previously written tapes examples 12 36 EXB 8200 format 12 36 EXB 8500 format 12 38 legal positions 3 3 ASC field 21 6 D 1 ASCQ field 21 6 D 1 Attention signal EXB 8500 response to 6 12 autosizing effect on value returned for Medium Type 13 9 initial estimates made during 3 of longer tape sizes 2 of shorter tape sizes 1 use of CT and P5 bits for 2 Blank Check 8h sense key D 6 Block Descriptor MODE SELECT command 1
208. hrough 0 LUNTRN The EXB 8500 is a single device target and does not support multiple devices therefore the LUN must be 0 December 1991 6 9 6 SCSI Physical Path Communications Message Sequence When the EXB 8500 connects to the SCSI bus the following sequence of events occurs 1 6 10 The initiator indicates its ability to accommodate more than the Command Complete message by asserting the Attention signal in the Selection phase before the Select signal is driven true and the Busy signal is driven false To indicate its ability to accommodate more than the Command Complete message the EXB 8500 responds to the Attention signal by transitioning to the Message Out phase immediately after completing the Selection phase If the initiator supports messages other than Command Complete the first message sent by the initiator after the Selection phase is the Identify message This allows the physical path to be established for the LUN specified by the initiator The EXB 8500 support an LUN of 0 only If the DiscPriv bit bit 6 in the Identify message is set the EXB 8500 may send the Disconnect message to the initiator to indicate that the physical path will be broken temporarily or If the DiscPriv bit is not set the EXB 8500 will not send the Disconnect message and will not temporarily suspend the physical path If the physical path has been broken temporarily the EXB 8500 will re establish the communication path with th
209. information to be reported for the designated logical unit This occurs when a command completes successfully or returns Check Condition status with the FMK EOM or ILI bits set to 1 th Recovered Error This sense condition is not supported by the EXB 8500 2h Not Ready Indicates that the EXB 8500 does not contain a data cartridge or that the data cartridge is not loaded Operator intervention may be required to correct this condition 3h Medium Error Indicates that the command terminated with a non recoverable error condition that may have been caused by a flaw in the tape 4h Hardware Error Indicates that the EXB 8500 detected a non recoverable hardware failure while performing the command or during a self test 5h Illegal Request Indicates that there was an illegal parameter in the CDB or in the additional parameters supplied as data for some commands or that the EXB 8500 is in the wrong mode to execute the command 6h Unit Attention Indicates that the EXB 8500 has been reset by a power on reset a Bus Device Reset message or a SCSI bus reset that an initiator changed the MODE SELECT parameters since the last command was issued to the EXB 8500 or that the data cartridge was changed This sense key is reported the first time any command is issued by each initiator after the condition is detected and the requested command is not performed This sense key is cleared when the ne
210. ing on the EXB 8500 s EEPROM image the EXB 8500 performs one of the following actions when it receives tape motion commands during a load operation It queues holds tape motion commands and disconnects if allowed until the load operation is complete Then it executes the commands It returns Busy status It returns Check Condition status with the sense key set to Not Ready Note If another initiator has reserved the EXB 8500 for its exclusive use the EXB 8500 returns Reservation Conflict status For information about these status conditions see Section 7 4 December 1991 3 15 3 Operating the EXB 8500 Load Time The time required to load the data cartridge and position the tape to LBOT after the door is closed is approximately 30 seconds for a rewound cartridge When loading a tape the EXB 8500 spaces forward from PBOT and determines the tape format blank EXB 8500 format or EXB 8200 format In addition when the EXB 8500 spaces forward it determines the adaptive servo parameters This process enables the EXB 8500 to read tapes produced by different manufacturers tapes that are aged and worn and tapes written by other EXABYTE 8mm Cartridge Tape Subsystems Finally during a load operation the EXB 8500 autosizes the data cartridge that is it determines the length of the tape in use For information about data cartridge autosizing refer to Appendix C 3 8 Unload Procedure This section describes what happe
211. initiator to specify medium logical unit or device parameters These values apply to all initiators in a multi initiator environment 12 1 Field Definitions Byte 01 Bit 4 PF Page Format The PF bit indicates in which format the MODE SELECT parameters are specified as follows 0 MODE SELECT parameters after the Block Descriptor are vendor specific non page format 1 MODE SELECT parameters after the Block Descriptor are structured as pages of related parameters page format Non page format is the same as that defined for the EXB 8200 Byte 01 Bit 0 SP The EXB 8500 does not support the saved page function The valid value for this bit is 0 December 1991 12 1 12 MODE SELECT 15h 12 2 Byte 04 Parameter List Length Non Page Format The Parameter List Length byte indicates the length of the parameter list that will be transferred from the initiator to the EXB 8500 during the Data Out phase When the PF bit is set to O non page format all parameters after the Block Descriptor are vendor specific and the Parameter List Length byte can contain values ranging from 00h to 11h The value for this byte must represent the total number of bytes to be transferred from the initiator to the EXB 8500 Table 12 1 lists the valid lengths for the Parameter List Length byte for non page format When the value for the Parameter List Length byte 15 0 no data is transferred from the initiator A value of 0 for this byte is
212. ion 3 17 Not Ready 2h sense key D 2 O operation code format of 7 3 13 1 510201 P5 data cartridge track and block counts EXB 8200 format 7 track and block counts EXB 8500 format 6 P6 data cartridge track and block counts EXB 8200 format 7 track and block counts EXB 8500 format 6 packing the EXB 8500 4 3 page format MODE SENSE command 13 2 Parameter List Header MODE SELECT command 12 7 SENSE command 13 8 parameter list length MODE SELECT non page format 12 2 MODE SELECT page format 12 4 SEND DIAGNOSTIC 24 2 parity error in system supporting additional messages 6 12 in systems supporting Command Complete message 6 11 Message Parity Error message 6 8 PBOT defined 4 detected during space 25 4 PEOT defined C 5 detected during locate 11 4 detected during read 15 5 detected during space 25 4 detected during verify 27 4 detected during write 28 9 detected during write filemarks 30 4 PF field MODE SELECT command 12 1 physical beginning of tape See PBOT physical blocks counts for EXB 8200 format 7 counts for EXB 8500 format 6 general format of 3 4 physical end of tape See PEOT physical path communications PI data cartridge track and block counts EXB 8200 format 7 track and block counts EXB 8500 format 6 pin assignments for remote connector 2 6 power cable requirements A 7 power connector pin assignments A 7 power connecting EXB 8500 to 2 12 power on defaults
213. ion Conflict status 7 9 RESERVE UNIT 16h command resetting the EXB 8500 data cartridge not present 6 42 data cartridge present 6 41 effect of power on reset 6 40 effect of SCSI bus and device resets 6 41 resistor terminators 2 10 Restore Pointers 03h message 6 6 REWIND 01h command 23 1 23 2 RTF field MODE SENSE command 13 31 S safety standards for EXB 8500 1 6 Save Data Pointer 02h message 6 6 SCSI bus cable connector for 5 cable requirements A 3 A 8 connecting the EXB 8500 to 2 10 external terminators 2 1 internal terminators for 2 10 message system for 6 4 physical characteristics of 6 3 SCSI bus error recovery in systems supporting additional messages 6 12 in systems supporting Command Complete message 6 11 SCSI bus reset 6 41 SCSI cable connecting to EXB 8500 2 11 differential SCSI A 4 general requirements for A 3 single ended SCSI A 4 SCSI command set See commands SCSI ID methods for setting 2 3 setting with DIP switches 2 4 setting with jumpers 2 7 setting with remote switch 2 5 SCSI instruction trace table 19 7 search fields 3 5 Selection phase 6 13 SEND DIAGNOSTIC 1Dh command diagnostic tests 24 3 field definitions for 24 2 sense key values for 21 3 D 1 D 8 serial number for EXB 8500 9 8 servo head 3 4 shipping carton 4 3 shipping the EXB 8500 4 3 22 1 22 2 l 6 single ended SCSI cable requirements for A 4 installation procedure for 2 10 pin assignments for cable connector
214. ion Length field specifies the number of bytes that the initiator has allocated for the return of RECEIVE DIAGNOSTICS RESULTS data m If you are using the command to obtain diagnostic data the number of bytes of diagnostic data available from the EXB 8500 depends on the type of SEND DIAGNOSTIC test that was performed see Section 19 2 for more information To receive all available diagnostic information the value in the Allocation Length field should equal the Page Length for the diagnostic page requested plus 4 bytes A value of 0 for the Allocation Length field indicates that no diagnostic data will be returned and is not an error or m If you are requesting a trace of SCSI and servo activity specify 500h for the Allocation Length field The EXB 8500 terminates the Data In phase when the number of bytes specified in the Allocation Length field has been transferred or when all available data has been transferred to the initiator whichever is less Byte 05 Bit 7 TD Trace Dump This bit indicates whether you are requesting diagnostic data or a trace dump as follows 0 Return diagnostic data see Section 19 2 for more information 1 Return a trace of SCSI and servo activity see Section 19 3 for more information Byte 05 Bit 6 VU Vendor Unique There is no vendor unique definition for this bit 19 2 510201 19 RECEIVE DIAGNOSTIC RESULTS 1 19 2 Returning SEND DIAGNOSTIC Data When the initiator iss
215. isolate the error condition When the READ command is terminated the EXB 8500 is positioned after the unrecovered block for a Medium Error or in an undefined position for a Hardware Error If the Valid bit is set to 1 the Information bytes are set to either of the following m The requested transfer length if the Fixed bit is set to 0 m The difference between the requested transfer length and the actual number of blocks read if the Fixed bit is set to 1 The actual number does not include the unrecovered block In both fixed and variable block modes the EXB 8500 may have entered the Data Phase before reporting this error December 1991 15 5 15 READ 08h 15 6 Transfer Length Incorrect If the actual transfer length does not match the requested transfer length the information reported depends on the setting of the Fixed bit Variable Length Mode If the Fixed bit is set to O and the actual length of the block on the tape does not match the transfer length requested the EXB 8500 transfers the number of bytes available up to the transfer length requested Then the EXB 8500 terminates the READ command and returns Check Condition status 1f the SILI bit is set to 0 The Illegal Length Indicator ILI bit and the Valid bit are set in the extended sense data with the sense key set to No Sense Oh The Information bytes indicate the difference between the actual and the requested lengths as follows m If the requested lengt
216. ite EXB 8500 format tapes EXB 8500 format 00h error checking This Density Code is ignored does not return Check suppressed Condition status if you attempt to use it to change the tape format from EXB 8200 to EXB 8500 when the tape is not positioned at LBOT Use this Density Code at LBOT if you want to write EXB 8200 format tapes 14h ERE d The EXB 8500 returns Check Condition status with the 9 sense key set to Illegal Request 5h if you attempt to use this Density Code to change the tape format from EXB 8500 to EXB 8200 when the tape is not positioned at LBOT Use this Density Code at LBOT if you want to write EXB 8500 format tapes 15h uS ALS The EXB 8500 returns Check Condition status with the 9 sense key set to Illegal Request 5h if you attempt to use this Density Code to change the tape format from EXB 8200 to EXB 8500 when the tape is not positioned at LBOT No change in the c this Density Code if you do not want to change the tape ormat 7Fh format is desired d pude The format will remain the same as it was before the MODE Pp SELECT command was sent to the EXB 8500 12 10 Restrictions for Setting the Density Code m entire tape must be written in the same density That is the Density Code applies to the entire tape not to individual blocks and files You can change the Density Code only when the tape is positioned at LBOT m For read operations the EXB 8500 automatically determines the correct d
217. iting the number of gap blocks specified by this byte the EXB 8500 will either continue the write operation if there is new data in the buffer or begin the process to stop tape motion if the buffer is still empty Before actually stopping tape motion the EXB 8500 writes additional gap blocks to complete the current track and then writes one or two complete gap tracks See the EXB 8500 8mm Cartridge Tape Subsystem Product Specification for more information Values returned for the Gap Threshold byte range from 00h to 07h The default value is 07h Byte 03 Active Partition The Active Partition byte is not supported by the EXB 8500 The value returned for this byte is 0 Byte 04 Write Buffer Full Ratio The Write Buffer Full Ratio represents the amount of data that must be present in the buffer during a buffered write operation before that data is written to the tape The value is expressed in 4 KByte increments The default value for this byte is 80h 512 KBytes Values range from 20h to DOh 128 to 832 KBytes 13 26 510201 13 MODE SENSE Byte 05 Read Buffer Empty Ratio The Read Buffer Empty Ratio represents how empty the buffer must be during a buffered read operation before additional data will be read from the tape The value is expressed in 4 KByte increments The default value for this byte is 80h 512 KBytes Values range from 20h to DOh 128 to 832 KBytes The Read Buffer Empty Ratio equals the Write B
218. ity Code is set for EXB 8200 format Note If the tape has been previously written the value returned for the Number of Blocks field represents the tape s present format not the format set with the Density Code field That is the format of any data already on tape has precedence over the format set with the Density Code Bytes 05 through 07 Block Length The Block Length field defines the length in bytes of each logical block described by the Block Descriptor A value of 0 for the Block Length field indicates variable length logical blocks A value greater than 0 indicates fixed length logical blocks The power on default value for the block length 15 400h 1 024 bytes The limit on the block length is the maximum block length specified in the READ BLOCK LIMITS 05h command 510201 13 MODE SENSE 13 4 Vendor Unique Parameters Non Page Format Bit 7 6 5 4 3 2 1 0 Byte 00 CT RSVD ND RSVD NBE EBD PE NAL 01 Reserved P5 02 Motion Threshold 03 Reconnect Threshold 04 Gap Threshold December 1991 Field Definitions These vendor unique parameters apply only to non page format Page Code field in the CDB is 0 Byte 00 Bit 7 CT Cartridge Type This bit reports what type of data cartridge is expected to be loaded in the EXB 8500 0 P6 Cartridge Type Domestic PI Cartridge Type International P5 P6 LEOT equivalency See Appendix C for i
219. k for Six Byte Command Bit 7 6 5 4 3 2 1 0 Byte 00 Operation Code 01 Logical Unit Number Vendor 02 MSB 03 Logical Block Address 04 LSB 05 Control Byte 7 2 510201 7 8500 SCSI Command Set Command Descriptor Block for Ten Byte Command Bit 7 6 5 4 3 2 1 0 Byte 00 Operation Code 01 Logical Unit Number Vendor 02 MSB Logical Block Address 05 LSB 06 Reserved 07 MSB Transfer Parameter List or Allocation Length 08 LSB 09 Control Byte Format of the Operation Code Bit 7 6 5 4 3 2 1 0 Byte 00 Group Code Command Code Typical Format of the Control Byte Bit 7 6 5 4 3 2 1 0 Byte nn Vendor Unique Reserved Flag Link December 1991 7 3 7 8500 SCSI Command Set 7 2 Field Definitions for the Command Descriptor Block The following sections provide field definitions for the six and ten byte command descriptor blocks CDB Field Definitions for Six Byte CDBs The following are the definitions of the fields shown for the six byte CDB Byte 00 Operation Code The Operation Code consists of two subfields the Group Code and the Command Code which are defined as follows Bits 7 through 5 Group Code The Group Codes supported by the EXB 8500 are defined by the specific c
220. l and that a later reconnect is required to complete the current operation If it does not send either this message or the Command Complete message before going to the Bus Free phase other than as a result of the reset condition the EXB 8500 indicates either of the following m A catastrophic error condition has occurred on the current command m The initiator aborted the command Note This message should not cause the initiator to save the data pointer Initiator Detected Error 05h The initiator sends the Initiator Detected Error message to inform the EXB 8500 that an error has occurred that does not preclude the EXB 8500 from retrying the operation The present pointer integrity is not ensured Abort 06h The initiator sends the Abort message to the EXB 8500 to clear the present operation If a LUN has been identified in the Identify message must be 0 all pending data and status for the issuing initiator is cleared and the EXB 8500 goes to the Bus Free phase If no Identify message has been sent or if the LUN is not 0 the EXB 8500 goes to the Bus Free phase No status or ending message is sent for the operation If a process is aborted the EXB 8500 generates sense data that indicates how the process terminated either aborted or an error condition Message Reject 07h Either the EXB 8500 or the initiator can send the Message Reject message to indicate that the last message received was inappropriate or has not been impl
221. last track containing the LBOT information You cannot alter or access the data contained in the LBOT blocks The tape can be repositioned and a write operation can be performed to erase the LBOT and record a new LBOT in the same space This process occurs for example when a write operation is performed at LBOT on a previously written tape 510201 December 1991 Appendix C Data Cartridge Capacities If a read after write check indicates an error while the EXB 8500 is writing LBOT the blocks are not rewritten Errors in writing the LBOT blocks are not reported to the initiator If excessive read after write checks occur the tape is rewound and the entire process is repeated If the retry fails a media error is reported During read operations LBOT blocks are not transferred to the initiator Logical End of Tape LEOT The logical end of tape LEOT is determined by the number of recorded tracks that occur after LBOT For this purpose lengths of erased segments are converted into an equivalent number of tracks Physical End of Tape PEOT The physical end of tape PEOT is located at the point on the tape where the translucent trailer material is attached to the media This position is detected by an optical sensor in the tape transport mechanism 5 Appendix C Data Cartridge Capacities Table C 3 Track and Physical Block Counts for EXB 8500 Format Cartridge Cartridge LBOT to LEOT LEOT to PEOT Type Size T
222. le 24 1 Valid Combinations of SEND DIAGNOSTIC Fields 24 3 Table 24 2 Values for SEND DIAGNOSTIC Command Parameter List Length 24 4 SPACE 11h Table 25 1 Code Values for the SPACE Command 25 2 WRITE 0Ah Table 28 1 Action of EXB 8500 If LEOT Is Encountered during a WRITE Command Oe De eee owe y Peg 28 6 WRITE BUFFER 3Bh Table 29 1 Time Required to Load Code with WRITE BUFFER Command 29 3 WRITE FILEMARKS 10h Table A 1 Specifications for the SCSICable A 4 Table A 2 Connector Pin Assignments for Differential EXB 8500s A 5 Table A 3 Connector Pin Assignments for Single ended EXB 8500s A 6 Table A 4 Pin Assignments for the EXB 8500 Power Connector 7 Data Cartridge Capacities Table C 1 Combinations of CT and P5 Bits in MODE SELECT 15h Command C 2 Table C 2 Initial Autosizing Estimates Made by the EXB 8500 C 3 Table C 3 Track and Physical Block Counts for EXB 8500 Format C 6 December 1991 xvii Table 4 Track and Physical Block Counts for EXB 8200 Format C 7 Table C 5 Approximate Capacities of EXATAPE Data Cartridges C 8 Fault Symptom Codes Table E 1 Fault Symptom Codes Roo Rx RR RE E 2 Table E 2 Recommended Error Recovery Procedures 7 xviii 510201 Figures General Information Figure 1 1 EXABYTE EXB 8500 8mm Cartridge Tape
223. lity The EXB 8500 can write and read data in two tape formats m EXB 8500 format m EXB 8200 format Table 3 1 shows the compatibility of these formats with other EXABYTE 8mm Cartridge Tape Subsystems and with other tape formats Table 3 1 Read and Write Compatibility of EXABYTE 8mm Cartridge Tape Subsystems A tape written in this Can be written and read by an fonna EXB 8500 EXB 8200 EXB 8200SX 8205 EXB 8500c EXB 8500 format v v EXB 8200 format v v v v v EXB 8200c T compressed format EXB 8500c v compressed format 3 2 510201 3 Operating the EXB 8500 Controlling the Tape Format As described in the examples in Section 12 12 whenever you write append to or read a tape you should keep the following four rules in mind m The EXB 8500 allows only one format on any one tape m If you are writing data you must decide the tape s format at This is because the LBOT blocks define the format for the tape If you do not select a format the EXB 8500 writes in the power on default format Note rewrite a tape in a different format you must overwrite the previously written LBOT pattern by issuing a WRITE 0Ah or WRITE FILEMARKS 10h command at LBOT m If you are appending to a previously written tape at a location other than LBOT the EXB 8500 automatically writes in the format of the data already on the tape m If you are reading a previously w
224. loh 44 kesir degai 29 5 Y 39093 968 eR e ROS ys 20 5 30 WRITE FILEMARKS 30 1 30 1 Field Denmuonus oe a ew Hee sacs wer Red Ey UE 30 1 30 2 Tape uu 90 33x 9 9e x deg yox xe 30 3 30 3 Exceptions and Error Conditions 2 22222 2484488554444 30 4 Wr te Protected Data Cartridge 22 dew ROS 30 4 LEOT Encounters gt s e siie 5 VS 30 4 PEOT Encountered cu uoa ew baa eem bee BEE aed 30 4 Hntecoverable EHOF s a s emra es mt She eee Ge 30 5 Appendixes 4 aie ae ae a a ae UN ae NR A 1 Appendix A Cable Requirements A 3 Requirements forthe SCSI Cable n See 3 General Requirements e x x Rae db ace E Xu X REUS A 3 Cables for Differential SCSI Configurations 4 Cables for Single Ended SCSI Configurations s 4 Requirements for the SCSI Cable Connector A 5 Requirements for the Power Cable Connector 22v ro s 7 Appendix B EXB 8500 Directory Support B 1 Overview of EXB 3500 Directory Support 2 4 oe bw Be B 1 Sample Application for Directory Support 04 B 2 Writing Data for Directory Support
225. m Sending the Abort message m Performing a SCSI bus reset m Sending the Bus Device Reset message 6 35 6 SCSI Physical Path Communications Initial Phase Reselection with Identify In Transition to Message Out Identify Does initiator own current process Is Disconnect bit Yes set Allow disconnects Disallow disconnects Abort process Go Bus Free lt Continue processing C Rest 2 No Operation Go Bus Free Continue processing y Message Parity Abort process Error Send Message Reject IN Send Identify IN again y Set sense key to Aborted Command Bh Continue processing Send Check Condition Go to Status phase Figure 6 13 Message Processing after EXB 8500 Reselects Initiator with Identify Message 6 36 510201 December 1991 6 SCSI Physical Path Communications Message Processing during Disconnect Sequence Figure 6 14 shows how messages are processed while the EXB 8500 is executing the disconnect sequence Note that attempts to change the physical path characteristics are not allowed Also the disconnect sequence may be aborted if the initiator sends a Message Reject message Parity Error Sending Disconnect or Save Data Pointers Message In If the initiator detects a parity error when the EXB 8500 sends a Disconnect or Save Data Pointers message in it responds by sending
226. mation about the differences between EXB 8500 format and EXB 8200 format refer to the 8500 8mm Cartridge Tape Subsystem Product Specification Byte 03 Bit 1 Reserved This bit is reserved Byte 03 Bit 0 P5 This bit is set to 1 to indicate that the data cartridge loaded in the EXB 8500 is expected to be a P5 European data cartridge When set to 1 this bit overrides the CT bit See Appendix C for information about data cartridge capacities and for an explanation of how the EXB 8500 autosizes data cartridges Byte 04 Motion Threshold The value in the Motion Threshold byte indicates the amount of data that must be in the buffer before tape motion is started for a buffered write or read operation The value is expressed in 4 KByte increments The default is 80h 512 KBytes Values range from 20h to DOh 128 to 832 KBytes When the buffer is filled to this point during a buffered write operation tape motion begins and data is written to the tape When the buffer is emptied to this point during a buffered read operation tape motion begins and data is read filling the empty portion of the buffer with new data from the tape 13 32 510201 December 1991 13 MODE SENSE Byte 05 Gap Threshold The Gap Threshold byte indicates the maximum number of consecutive gap blocks that the EXB 8500 will write on the current track while determining whether an empty buffer exists during a write operation After writing th
227. minates the WRITE FILEMARKS command and returns Check Condition status The sense key indicates a Medium Error 3h or Hardware Error 4h Indicators in the extended sense data can be used to isolate the error condition If the Valid bit is set to 1 the Information bytes contain the difference between the requested number of filemarks and the actual number of filemarks written If another WRITE FILEMARKS command is issued after an unrecoverable error occurs the EXB 8500 returns Check Condition status with the sense key set to Medium Error or Hardware Error and the command is not executed 30 5 30 WRITE FILEMARKS 10h Notes 30 6 510201 Appendixes Appendix A Cable Requirements This appendix lists the requirements for the SCSI cable and the power cable for the EXB 8500 It also lists the power supply requirements Requirements for the SCSI Cable The SCSI cable for connecting the EXB 8500 to the host is not provided with the EXB 8500 You must provide a cable that complies with the appropriate safety and regulatory agency requirements To comply with FCC CSA and VDE rules the EXB 8500 requires shielded cables when the cables are external to the mounting enclosure Note The SCSI cable requirements depend on whether you are using a single ended or differential SCSI configuration General Requirements Ideally to match the cable terminators the cable should have a characteristic impedance of 122 ohms differential or
228. mines the tape s format Writing and Reading in EXB 8500 Format This section describes how to use the EXB 8500 to write append to and read tapes in EXB 8500 format This format is compatible with the following EXABYTE products m EXB 8500 m EXB 8500c Writing EXB 8500 Format Tapes To write tapes in EXB 8500 format follow these steps 1 Load a blank data cartridge in the EXB 8500 or load a previously written data cartridge that you want to overwrite 2 Issue a MODE SELECT command at LBOT Set the Density Code in the Block Descriptor to 15h or 00h Note Refer to page 12 40 if you cannot issue MODE SELECT commands 3 Issue WRITE or WRITE FILEMARKS command to write the data 510201 December 1991 12 MODE SELECT 15h Appending to EXB 8500 Format Tapes If a tape has already been written in EXB 8500 format and you want to write additional data on the tape follow these steps 1 Load the data cartridge in the EXB 8500 Note If you issue a MODE SELECT command at LBOT be sure that the Density Code in the Block Descriptor is set to 15h Issue a READ or SPACE command to move away from LBOT and to a legal position for appending Note Legal positions for appending in EXB 8500 format are either side of a long filemark and at the end of data EOD mark Issue a WRITE or WRITE FILEMARKS command to write the additional data The EXB 8500 automatically sets the Density Code to EXB 8500 format Note The WTF bi
229. n condensing Wet Bulb 26 C max 79 F max Altitude 304 8 m to 12 192 1 000 ft to 40 000 ft December 1991 4 5 4 Cleaning and Packing the EXB 8500 Notes 4 6 510201 5 Loading New Microcode from Tape This chapter describes the steps and time involved in using and creating a microcode update tape This tape is used to upgrade the EXB 8500 to a new level of microcode You can obtain a microcode update tape from EXABYTE when a new firmware release becomes available or you can create your own with the CTS Monitor program 5 1 Using a Microcode Update Tape When a microcode update tape is inserted into the EXB 8500 the EXB 8500 automatically detects its presence and upgrades the microcode to the new level No operator intervention is needed other than inserting the tape into the EXB 8500 To use a microcode update tape follow these steps 1 Disconnect the EXB 8500 from the SCSI bus by unplugging the SCSI connector from the back of the unit If the location of the EXB 8500 makes removing the cable inconvenient ensure that a SCSI bus reset cannot occur during the microcode update process 2 Apply power to the EXB 8500 and wait for it to complete its power on self test 3 Insert the microcode update tape in the EXB 8500 and close the door Steps During Microcode Update Process The following steps occur automatically when you insert a microcode update tape in the EXB 8500 1 The EXB 8500 loads the tape rea
230. n to be performed The only operation supported by the EXB 8500 is reading the microcode image The bits in this field must be set to 0016 Byte 02 Buffer ID This field must be 0 December 1991 17 1 17 READ BUFFER 3Ch Bytes 03 through 05 Buffer Offset This field must be Bytes 06 through 08 Allocation Length The Allocation Length field specifies the number of bytes to be transferred across the SCSI bus The valid value for this field 15 2AE28h 175 656 Byte 09 Bits 7 and 6 Vendor Unique There are no vendor unique definitions for this command 17 2 Exceptions and Error Conditions The following exceptions and error conditions can occur with the READ BUFFER command Hardware or SCSI Bus Error If a hardware or SCSI bus error occurs while the microcode is being transferred from the EXB 8500 to the initiator the EXB 8500 terminates the command and returns Check Condition status The sense key is set to Aborted Command Bh If this occurs retry the operation Allocation Length Incorrect If the initiator specifies a value other than 2AE28h 175 656 for the Allocation Length field the EXB 8500 returns Check Condition status The sense key is set to Illegal Request 5h 17 2 510201 18 READ POSITION 34h Bit 7 6 5 4 3 2 1 0 Byte 00 0 0 1 1 0 1 0 0 01 Logical Unit Number Reserved BT 02 Reserved 08 09 Vendor Unique Reserved 0 0
231. ncludes the fast unload button setting optional the following actions occur when you press the unload button These steps assume that a data cartridge is loaded and that the EXB 8500 is ready 1 3 18 Any command or activity currently in progress is aborted Note Ifthe EXB 8500 is performing a write operation when you press the fast version of the unload button the EXB 8500 will abort the command after it writes to tape the last logical block that was completely transmitted from the initiator However any partially transmitted logical blocks will be lost If necessary an EOD mark is written to the tape to indicate the end of data The tape is rewound to the physical beginning of tape PBOT The tape is unloaded from the tape path The EXB 8500 s door is opened and the data cartridge is ejected unless media removal has been prevented with the PREVENT ALLOW MEDIUM REMOVAL command CAUTION When you use the fast version of the unload button to unload the tape the data in any partially transmitted logical blocks is lost not put on tape for a write operation or not sent to the initiator for a read operation 510201 3 Operating the EXB 8500 Super Fast Unload If the EXB 8500 s EEPROM image includes the super fast unload button setting optional the following actions occur when you press the unload button These steps assume that a data cartridge is loaded and that the EXB 8500 is ready
232. ncountered during a space or locate 36h operation 3Bh 02h PEOT encountered Tape position error at end of medium 14h 50h Oth Write failure after retry limit specified with MODE SELECT 95h exceeded December 1991 D 3 Appendix D Sense Key Information Sense Key 4h Hardware Error ASC ASCQ Related Byte 12 Byte 13 ExPianallon FSC 58h 5Ah l 67h 68h 00h 00h Undetermined hardware error 6Dh FAh FCh FDh 08h 01h Logical unit communication time out xai 08h 02h Logical unit communication parity error A3h A8h OCh 00h Hardware failure Head sync error during write Aih 11h Hardware Error was detected during a read operation 17h 15h 01h Servo hardware failure ADh 8Ch 98h 44h 00h Internal software failure 99h A2h ACh D 4 510201 Appendix D Sense Key Information Sense Key 5h Illegal Request ASC ASCQ Related Byte 12 Byte 13 EXpranagen FSC 00h 05h The EXB 8500 was not in a legal mode to read in write mode or OEh not ready 1Ah 00h Illegal transfer length in the CDB CCh D4h 20h 00h Illegal operation code CDh 2th 00h Logical block out of range D9h 24h 00h Invalid field in the CDB CEh 25h 00h Logical unit not supported CFh D1h 26h 00h Invalid field in parameter list DOh 30h 02h Cannot read the tape position Incompatible format D7h 3Dh 00h Ille
233. nd EOT side of a long filemark m The end of data mark EOD If the tape is not positioned at one of these locations the EXB 8500 returns Check Condition status with the sense key set to Illegal Request Appending Data EXB 8200 Format Tapes When writing to tape in EXB 8200 format the EXB 8500 can append new data to existing data if the tape is positioned at either of the following locations m The beginning BOT side of a long filemark m The end of data blank tape If the tape is not positioned at either of these locations the EXB 8500 returns Check Condition status with the sense key set to Illegal Request 28 3 28 WRITE 0Ah 28 3 Data Buffering The EXB 8500 provides two modes of operation for the WRITE command unbuffered and buffered The mode of operation is set with the MODE SELECT command byte 02 bits 6 through 4 in the Parameter List Header Unbuffered Write Operation When the EXB 8500 is set for an unbuffered write operation it returns Good status as soon as all data blocks are written to tape Buffered Write Operation When the EXB 8500 is set for a buffered write operation it returns Good status as soon as all data blocks are successfully transferred to the buffer The data in the buffer is written to tape when one of the following conditions occurs m The motion threshold is reached during a WRITE command see Section 3 2 m The EXB 8500 receives one of the following commands REWIND 01h WR
234. nformation about data cartridge capacities and for an explanation of how the EXB 8500 autosizes data cartridges Byte 00 Bit 6 RSVD This bit is reserved Byte 00 Bit 5 ND No Disconnect During Data Transfer This bit indicates whether the EXB 8500 can disconnect from the initiator during the data transfer phase 0 The EXB 8500 can disconnect from the initiator during the data transfer phase 1 The EXB 8500 will not disconnect during the data transfer phase The power on default for ND is 0 13 15 13 MODE SENSE Restrictions when the ND bit is 0 m The maximum logical block size allowed in fixed or variable mode is 240 KBytes 3C000h Restrictions when the ND bit is 1 m The total number of bytes that can be transferred as a result of a single WRITE or READ command in fixed or variable mode is 160 KBytes 28000h That is the total transfer length specified by the CDB must be 160 KBytes or less m The maximum logical block size allowed in fixed or variable mode is 160 KBytes m During a write operation the data transfer from the initiator does not start until the number of bytes of available space in the EXB 8500 s buffer is greater than or equal to the total transfer length specified by the CDB m During a read operation the data transfer to the initiator does not start until all of the data requested by the CDB up to a total transfer length of 160 KBytes is resident in the EXB 8500 s bu
235. nly for page format and must 0 for non page format 510201 13 MODE SENSE Byte 02 Bits 5 through 0 Page Code The Page Code field indicates which MODE SENSE parameter page or pages the initiator is requesting A value of 0 for this field indicates that the parameters will be returned in non page format Table 13 1 lists the values supported by the EXB 8500 for the Page Code field Table 13 1 Values for Page Code Field in the MODE SENSE Command To return the Specify this Page And this information will be parameters in Code returned 1 to 5 bytes of vendor unique Non page tuumal parameters in non page format 01h Read Write Error Recovery Page 02h Disconnect Reconnect Page OFh Data Compression Page Page lonmat 10h Device Configuration Page 20h Vendor Unique Parameters Page 1 21h Vendor Unique Parameters Page 2 3Fh All six available pages If you specify 0 for the Page Code field ensure that the DBD bit is also set to 0 Otherwise the EXB 8500 will return Check Condition status with the sense key set to Illegal Request 5h When the Page Code is set to 3Fh all six available pages the pages are returned in the following order as specified in the ANSI SCSI 2 standard Read Write Error Recovery Page Disconnect Reconnect Page Data Compression Page Device Configuration Page Vendor Unique Parameters Page 1 Vendor Unique Parameters Page 2
236. nnect Reconnect Page Page Codez02h Page Format 12 MODE SELECT 15h Bit 7 6 5 4 3 2 1 0 Byte 00 Reserved Page Code 01 Page Length 02 Buffer Full Ratio 03 Buffer Empty Ratio 04 MSB Bus Inactivity Limit 05 LSB 06 MSB ce Disconnect Time Limit 07 LSB 08 MSB Connect Time Limit 09 LSB 10 MSB 1 Maximum Burst Size 11 LSB Field Definitions The Disconnect Reconnect Page specifies parameters for disconnects and reconnects These parameters apply only to page format that is when the PF bit in the CDB is set to 1 Byte 00 Bits 5 through 0 Page Code The Page Code identifies the type of MODE SELECT page being transferred This is the Disconnect Reconnect Page The valid value for Page Code is 02h Byte 01 Page Length The Page Length indicates the number of bytes in the Disconnect Reconnect Page that follow this byte The valid value for this byte is OAh December 1991 12 19 12 MODE SELECT 15h 12 20 Byte 02 Buffer Full Ratio The Buffer Full Ratio represents the amount of data that must be present in the buffer during a buffered read operation before the EXB 8500 will attempt to reconnect to the initiator The value is expressed in 4 KByte increments The default value for the Buffer Full Ratio is 80h 512 KBytes Valid values range from 20h to DOh 128 to 832 KBytes Note Ifthe ND bit is 1 and you se
237. ns when you press the unload button for information about using the LOAD UNLOAD 1Bh command see Chapter 10 Unload Button Options Three options are available from EXABYTE to control what happens when you press the unload button Depending on the EXB 8500 s EEPROM image the unload button can function in one of three ways m Asa normal unload button default m Asa fast unload button m Asa super fast unload button This section describes each of these options 3 16 510201 December 1991 3 Operating the EXB 8500 Normal Unload If the EXB 8500 s EEPROM image includes the normal unload button setting default the following actions occur when you press the unload button These steps assume that a data cartridge is loaded and that the EXB 8500 is ready 1 Any command or operation currently in progress is completed 2 Any buffered data and filemarks are written to tape and an EOD mark is written to indicate the end of data EXB 8500 format tapes only 3 The tape is rewound to the physical beginning of tape PBOT 4 The tape is unloaded from the tape path 5 The EXB 8500 s door is opened and the data cartridge is ejected unless media removal has been prevented with the PREVENT ALLOW MEDIUM REMOVAL command Note Ifthe unload button is pressed and there is no data cartridge in the EXB 8500 the door is opened 3 17 3 Operating the EXB 8500 Fast Unload If the EXB 8500 s EEPROM image i
238. nt Cables for Single Ended SCSI Configurations For single ended SCSI configurations use a 50 conductor flat cable or 25 signal twisted pair bus Ensure that the length of the cable does not exceed 6 0 meters 19 68 feet A stub length of no more than 0 1 meters 4 inches is allowed off the mainline interconnection within any connected equipment 510201 Requirements for the SCSI Cable Connector December 1991 Appendix A Cable Requirements The SCSI connector labeled P3 is located at the rear of the EXB 8500 The connector is a 50 pin male ribbon cable connector consisting of two rows of 25 pins with adjacent pins 2 54 mm 0 1 inch apart The connector has locking ejector tabs The stub length within the device is less than 50 mm To connect the EXB 8500 to the SCSI bus use a 50 pin female ribbon cable connector Amphenol9 No 1 7462855 0 or equivalent Table A 2 shows the connector pin assignments for differential EXB 8500s Table A 3 shows the connector pin assignments for single ended EXB 8500s Table A 2 Connector Pin Assignments for Differential EXB 8500s Signal SHIELD GROUND DIFFSENS GROUND TERMPWR GROUND ATN GROUND BSY ACK RST MSG SEL C D REQ GROUND 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 Pin Number 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 TERMPWR GROUND ATN GROUND BSY RST MSG SEL C D REQ l O
239. ntirety that is all 8 bytes partial transfers of this data segment are not allowed m Valid transfer lengths for vendor unique parameters are 0 1 2 3 4 and 5 bytes All transfers of the vendor unique parameters start with byte 0 13 4 510201 December 1991 13 MODE SENSE Byte 04 Allocation Length Page Format The Allocation Length byte indicates the amount of memory in bytes that the initiator has allocated for the return of MODE SENSE parameters from the EXB 8500 When the Page Code field is set to a non zero value the EXB 8500 returns either one or six pages of related parameters plus the Parameter List Header and the Block Descriptor if specified Table 13 3 shows the minimum values you can specify for the Allocation Length when the Page Code field is set to a non zero value Note that specifying FFh for the Allocation Length is not an error As indicated in the table values for the Allocation Length byte depend on the following m Which parameter page is being returned m Whether you want the Block Descriptor to be returned that is whether you set the DBD bit to O or 1 Note To return the Parameter List Header or the Block Descriptor without pages set the Page Code to 0 non page format and refer to Table 13 2 to determine what to specify for the Allocation Length field 13 5 13 MODE SENSE 1Ah Table 13 3 Allocation Lengths Page Format Specify at least this
240. o read or from read to write m The 8500 is reset The counter does not roll over from FFh to 0 but remains at FFh until reset Byte 12 Additional Sense Code ASC The Additional Sense Code in conjunction with the Additional Sense Code Qualifier byte 13 provides additional information about each sense key Appendix D lists the possible combinations of this byte and the ASCQ byte for each sense key Only those ASC values used by the EXB 8500 are shown in the appendix Byte 13 Additional Sense Code Qualifier ASCQ The Additional Sense Code Qualifier in conjunction with the Additional Sense Code byte 12 provides additional information about each sense key Appendix D lists the possible combinations of this byte and the ASC byte for each sense key Only those ASCQ values used by the EXB 8500 are shown in the appendix Bytes 14 and 15 Reserved These bytes are reserved 21 6 510201 December 1991 21 REQUEST SENSE 03h Bytes 16 through 18 Read Write Data Error Counter The Read Write Data Error Counter is a dual function counter for logging rewrites and read ECCS for recovered physical blocks physical block size is 1KByte The mode of operation determines what is being counted The counter is incremented in write mode when a specific physical block is rewritten following a read after write failure The counter is incremented in read mode when the physical block was reconstructed in the formatter by the Error Corr
241. o the SCSI bus the SCSI bus goes to the Bus Free phase m The servo is reset and a servo self test is performed m All EXB 8500 parameters are reset to their default states m A test of the microprocessor s external memory is performed After a SCSI bus or device reset the EXB 8500 will respond on the SCSI bus within 250 msec Note Ifthe device that supplies SCSI bus terminator power is powered off the RST line is left in an indeterminate state either reset or not depending on the voltages It may be impossible to communicate with the EXB 8500 or to unload a data cartridge when the device is in this state To remove the data cartridge restore power to the terminating device or remove the SCSI cable from the EXB 8500 to allow independent EXB 8500 operation Reset Processing This section describes how the EXB 8500 processes power on resets SCSI bus resets and device resets The EXB 8500 processes resets differently depending on whether or not a data cartridge is present Data Cartridge Present before Reset If a data cartridge is present before the reset occurs the tape is rewound and reloaded When the reset is complete the tape is positioned at the logical beginning of tape LBOT and the EXB 8500 is ready to process tape motion commands When a data cartridge is present the EXB 8500 responds to the reset as follows m It returns Check Condition status to the first command received The sense key is set to Unit Attention 6h
242. ocks to complete the current track and then writes one or two complete gap tracks See the EXB 8500 8mm Cartridge Tape Subsystem Product Specification for more information The Gap Threshold byte should be changed only when the average data transfer rate is slow and is impacting the capacity of the tape by forcing excessive start stop activity The Gap Threshold byte should be used in combination with the motion and reconnect thresholds described in this section Valid values for the Gap Threshold byte are 00h to FFh Any value greater than 07h is treated as 07h by the EXB 8500 The default value for the Gap Threshold byte is 07h 12 33 12 MODE SELECT 15h 12 10 Vendor Unique Parameters Page 2 Page Codez21h Page Format Bit 7 6 5 4 3 2 1 0 Byte 00 Reserved Page Code 01 Page Length 02 Reserved 03 Reserved WWR 04 Reserved 05 Reserved 12 34 Field Definitions This page applies only to page format that is when the PF bit in the CDB is set to 1 Byte 00 Bits 5 through 0 Page Code The Page Code identifies the type of MODE SELECT page being transferred This is Vendor Unique Parameters Page 2 The valid value for the Page Code is 21h Byte 01 Page Length The Page Length indicates the number of bytes in the Vendor Unique Parameters Page 2 that follow this byte The valid value for this byte is 04h Byte 02 Reserved This byte is reserved
243. ommand Bits 4 through 0 Command Code The Command Codes supported by the EXB 8500 are defined by the specific command Byte 01 Bits 7 through 5 Logical Unit Number LUN The LUN designates a specific unit within a group of devices associated with the target Since the EXB 8500 15 a single device target and does not support multiple devices the LUN must be 0 All command definitions in this manual show this field containing 0 Byte 01 Bits 4 through 0 Vendor These bits are used as defined in the specific commands Bytes 02 through 04 Logical Block Address These bytes are used as defined in the specific commands Byte 05 Control Byte The Vendor Unique portion of the Control byte is defined for each specific command if used The EXB 8500 does not support linked commands or recognize the Flag bit The following are the field definitions for the Control byte Bits 7 and 6 Vendor Unique Command unique Bits 5 through 2 Reserved These bits are reserved Bit 1 Flag Not used must be 0 Bit 0 Link Not used must be 0 7 4 510201 December 1991 7 8500 SCSI Command Set Field Definitions for Ten Byte CDBs The following are the definitions of the fields shown for the ten byte CDB Byte 00 Operation Code The Operation Code consists of two subfields the Group Code and the Command Code which are defined as follows Bits 7 through 5 Group Code The Group Codes supported by the EXB 8500 are defined by th
244. on Tape Positioned at LBOT When writing to tape positioned at LBOT in EXB 8500 or EXB 8200 format the EXB 8500 automatically writes a new LBOT pattern and then writes the requested number of filemarks Appending Filemarks EXB 8500 Format Tapes When writing to tape in EXB 8500 format the EXB 8500 can append filemarks to existing data if the tape is positioned at any of the following locations m The beginning BOT side of a long filemark m The end EOT side of a long filemark m The end of data mark EOD If the tape is not positioned at one of these locations the EXB 8500 returns Check Condition status with the sense key set to Illegal Request 5h Appending Filemarks EXB 8200 Format Tapes When writing to tape in EXB 8200 format the EXB 8500 can append filemarks to existing data if the tape is positioned at either of the following locations m The beginning BOT side of a long filemark m The end of data blank tape If the tape is not positioned at either of these locations the EXB 8500 returns Check Condition status with the sense key set to Illegal Request 5h 30 3 30 WRITE FILEMARKS 10h 30 3 Exceptions and Error Conditions The following exceptions and error conditions can occur with the WRITE FILEMARKS command Write Protected Data Cartridge If a write filemarks operation is attempted on a data cartridge that is write protected the EXB 8500 returns Check Condition status with the sense key set to
245. on 37h 3h 13 un MAS block was encountered during a space or locate 38h 3h 13 A Medium Error was detected during a space or locate operation 3Ah 9h 3 A wrong file number was encountered in a filemark during a space operation EXB 8200 format tapes only 3Bh Bh 11 The SPACE or LOCATE command was aborted as requested 4Bh 5h 11 The tape is not at legal place to erase or the EXB 8500 is not ready 4Ch 7h 5 The data cartridge is write protected and cannot be erased 4Eh Bh 11 The ERASE command was aborted as requested 58h 4h 11 An error occurred during the send diagnostics operation 5Ah 4h 11 An error occurred during the send diagnostics operation 61h 3h 11 The code header was in the wrong format when loading firmware 62h 3h 11 The servo load image was not valid 63h 3h 11 Bank 0 of control load image was not valid 64h 3h 11 Bank 1 of control load image was not valid 65h 3h 11 The EEPROM load image was not valid 66h 3h 11 The boot code did not allow a load from tape or the code version was not supported by the boot code 67h 4h 12 One of the memories could not be programmed 68h 4h 12 A Hardware Error occurred while loading new firmware 69h 3h 3 The CRC in the load image in the buffer was incorrect 6Dh 4h 12 The READ BUFFER command failed 8Ch 4h 8 Controller firmware logic error 95h 3h 6 9 Write failure after retry limit specified with MODE SELECT exceeded 96h 3h 6 Write filemark failure after internal retry limit e
246. on and the actual logical position Note If the EXB 8500 has the EEPROM image for directory support you can issue a LOCATE command with the ADE bit set to to move from the directory to the data area of the tape In this case the EXB 8500 spaces over the first EOD mark as long as it is located before the first filemark and does not return Check Condition status However when the EXB 8500 detects the second EOD mark at the end of data it returns Check Condition status with the sense key set to Blank Check 8h PEOT Encountered If the physical end of tape PEOT is encountered the EXB 8500 returns Check Condition status The EOM and PEOT bits are set in the extended sense data with the sense key set to Medium Error 3h When the LOCATE command terminates the logical position is the last logical position the EXB 8500 detected on tape If the Valid bit is set to 1 the Information bytes are set to the difference between the requested logical position and the last logical position detected Locating Past the Last Data or Filemark If you attempt to locate past the last data or filemark on the tape the EXB 8500 returns Check Condition status The sense key is set to Blank Check 8h 11 4 510201 December 1991 11 LOCATE 2Bh Unrecoverable Error If an unrecoverable media or hardware error occurs during the locate operation the EXB 8500 terminates the LOCATE command and returns Check Condition status The sense key indic
247. op on Consecutive Filemarks The SOCF field is not supported by the EXB 8500 The value returned for this field is 0 December 1991 13 27 13 MODE SENSE 13 28 Byte 08 Bit 1 RBO Recover Buffer Order The RBO bit is not supported by the EXB 8500 The value returned for this bit is 0 Byte 08 Bit 0 REW Report Early Warning The REW bit indicates whether the reporting of the early warning condition LEOT is enabled or disabled during a read operation 0 Do not report early warning condition for read operations default 1 Report early warning condition for read operations after completion of the current READ command The early warning condition is reported as a Check Condition status with the sense key set to No Sense The EOM bit is set to 1 and the LBOT and PEOT bits are set to 0 in the extended sense data Byte 09 Gap Size The Gap Size field is not supported by the EXB 8500 The value returned for this field is 0 Byte 10 Bits 7 through 5 EOD Defined The EOD Defined field is not supported by the EXB 8500 The value returned for this field is 0 Byte 10 Bit 4 EEG Enable EOD Generation The EEG bit indicates that the EXB 8500 will generate an EOD mark The EEG bit is set to 1 in the MODE SENSE data and is ignored by the MODE SELECT command Byte 10 Bit 3 SEW Synchronize at Early Warning The SEW bit indicates that the EXB 8500 will cause any buffered data to be written to the tape wh
248. or perform a space backward operation Otherwise attempting a space forward or locate operation to a position outside of the master directory will cause the command to fail with Check Condition status December 1991 B 7 Appendix B 8500 Directory Support Accessing Data on a Directory Support Tape To use the LOCATE command to access the data written in the previous section follow these steps 1 Readthe master directory to determine the locations of the data set directories on the tape MASTER DIR EOD 1 PAD LFM DS 1 DIR 1 DS n DIR n EOD 2 read master directory Note If you are using a LOCATE or SPACE command to position to data within the master directory be sure to set the ADE bit to 1 to prevent the EXB 8500 from crossing from the directory to the data area of the tape 2 Using the READ POSITION data from the master directory issue a LOCATE command to locate a specific data set directory for example DIR 2 Set the ADE bit to 0 so that the EXB 8500 will skip over the first EOD mark Read the data set directory to determine what files are contained in the data set If this directory does not list the file you want to locate continue issuing LOCATE commands and reading directories until you find the directory listing the file you need 1 Issue LOCATE command 3
249. ored when spacing to end of data 25 2 510201 25 SPACE 11h Byte 05 Bit 7 ADE Always Detect EOD The ADE bit is used only for those EXB 8500s that include the EEPROM image for directory support By setting this bit you can force the EXB 8500 to detect the first EOD mark on the tape effectively disabling directory support for that command The values for the ADE bit are as follows 0 The EXB 8500 should ignore the first EOD mark as long as it is located before the first filemark on the tape 1 The EXB 8500 should detect the first EOD mark on the tape and should stop when the first EOD is encountered If you are using a SPACE command to space forward within the directory on a directory support tape set the ADE bit to 1 to prevent the EXB 8500 from crossing from the directory to the data area of the tape Similarly set this bit to 1 if you are using an EXB 8500 with the directory support feature to space forward on a tape that does not include a directory Note ADE bit is ignored if the EXB 8500 does not include the directory support feature Byte 09 Bit 6 Vendor Unique There is no vendor unique definition for this bit 25 2 Exceptions and Error Conditions December 1991 The following exceptions and error conditions can occur with the SPACE command Filemark Detected If the Code field has a value of 000 space over n fixed or variable length blocks and a filemark is detected during a forward search
250. ower on reset m The MODE SELECT parameters are changed by an initiator other than the one attempting to communicate with the EXB 8500 m The unload button is pressed and the data cartridge is ejected m A data cartridge is inserted and automatically loaded m The internal microcode firmware is changed Effect of Changing Data Cartridges The first command received after the unload button on the front of the EXB 8500 is pressed receives Check Condition status with the sense key set to Unit Attention 6h Then all subsequent commands that require tape motion receive Check Condition status with the sense key set to Not Ready 2h Note Ifthe unload button is pressed and a data cartridge is already loaded the EXB 8500 will unload the tape The first command issued during the unload procedure receives Check Condition status with the sense key set to Unit Attention 6h All subsequent commands that require tape motion receive Check Condition status with the sense key set to Not Ready 2h When a data cartridge is inserted into the EXB 8500 the EXB 8500 returns Check Condition status with the sense key set to Unit Attention 6h If a data cartridge is inserted but the tape is not loaded that is autoload was disabled with a MODE SELECT command and a LOAD 1Bh command was not received the EXB 8500 returns Check Condition status with the sense key set to Not Ready December 1991 6 39 6 SCSI Physical Path Communications 6 40 Cl
251. ower on reset and self test 32 TOTAL 71 approx After the new code has been downloaded successfully the EXB 8500 returns Good status to the initiator that issued the WRITE BUFFER command It returns Check Condition status with the sense key set to Unit Attention 6h to commands sent by other initiators The ASC and ASCQ fields will be set to and and the Fault Symptom Code will be C3h 29 1 Field Definitions Byte 01 Bits 2 through 0 Mode The Mode field determines the type of operation to be performed The only operation supported by the EXB 8500 is downloading and saving the microcode The bits in this field must be set to 101b Byte 02 Buffer ID This field must be December 1991 29 3 29 WRITE BUFFER SBh 29 4 Bytes 03 through 05 Buffer Offset The value you specify for the Buffer Offset field depends on whether you are issuing one WRITE BUFFER command or several WRITE BUFFER commands as follows m If you are using one WRITE BUFFER command set this field to 0 m If you are using more than one WRITE BUFFER command set this field to the total number of bytes sent by the previous WRITE BUFFER commands in the command sequence Bytes 06 through 08 Parameter List Length The Parameter List Length field specifies the number of bytes to be transferred by the current WRITE BUFFER command The value you specify for this field depends on whether you are issuing one WRITE BUFFER command or several WRITE
252. path once a month or after 30 GBytes of data transfer whichever occurs first For planning purposes approximately 1 GByte of data is transferred per hour of operation in EXB 8200 mode December 1991 4 1 4 Cleaning and Packing the EXB 8500 To use the cleaning cartridge follow these steps 1 4 2 Apply power to the EXB 8500 When the power on self test is complete press the unload button and remove any data cartridge in the EXB 8500 Leave the door open Place the cleaning cartridge in the EXB 8500 and close the door The remainder of the cleaning cycle is performed automatically by the EXB 8500 When the cleaning cycle is complete the cleaning cartridge is unloaded and ejected from the EXB 8500 The average cleaning cycle is 15 seconds Record the date the cleaning was performed on the cleaning cartridge label Store the cleaning cartridge for future use Note Ifthe cleaning cartridge is ejected from the EXB 8500 without performing a cleaning cycle that is before 15 seconds the cleaning cartridge has reached the end of its useful life and should be discarded CAUTION To prevent contamination of the EXB 8500 do not use the cleaning cartridge for more than the number of cleaning cycles specified on the cartridge label 510201 4 Cleaning and Packing the EXB 8500 4 2 Packing the EXB 8500 for Shipment If you need to ship an EXB 8500 follow the instructions in this section Shipping Cartons The EXB
253. pe 18 Load new code into flash EPROMs 16 Perform a power on reset and self test first half until the tape is ejected 19 Perform a power on reset and self test 17 second half TOTAL 127 approx 5 Loading New Microcode from Tape 5 2 Creating a Microcode Update Tape You can use the CTS Monitor program to create a microcode update tape from a working EXB 8500 This process enables you to transfer the microcode from one EXB 8500 to another When you make a microcode update tape you can copy the servo code and control code only or you can copy the servo code control code and the portions of the EEPROM code that contain MODE SELECT power on defaults such as block size parity checking and even byte disconnect Normally you only need to copy the servo code and control code Steps for Making a Microcode Update Tape To make a microcode update tape follow these steps 1 5 4 Start the CTS Monitor program and select Firmware from the Main Menu Note If necessary refer to the Monitor User s Guide for instructions for starting and using the CTS Monitor program Select Make code tape from the Firmware Menu or press Alt N A prompt is displayed asking if you want to include the mode selectable portion of the EEPROM Press Y if you want the power on defaults for MODE SELECT to be copied to the tape press N if you do not want them to be copied or press Esc to cancel the operation A prompt is displ
254. pecific definitions that return Check Condition status refer to the command descriptions in Chapters 8 through 30 Check Condition status is reported when a command is received in the following cases m When there is a bus parity error or format check error in a CDB m When the command is the first command sent to the EXB 8500 after it was reset by a SCSI bus reset or a Bus Device Reset message or after the data cartridge was replaced The sense key in the sense data indicates Unit Attention 6h Busy Busy status indicates that the EXB 8500 is in the busy state The EXB 8500 is in a busy state when it is performing an internal operation that will not allow another command to be accepted until the operation is complete The EXB 8500 returns Busy status for a command request until the busy state 15 released For this reason the initiator must reissue the command to the EXB 8500 Once the busy state 15 released selection operation and commands can be executed normally Reservation Conflict Reservation Conflict status indicates that the EXB 8500 is currently reserved for the exclusive use of another initiator This status is reported until the initiator that reserved the EXB 8500 issues a RELEASE UNIT command or a reset condition occurs December 1991 7 9 7 8500 SCSI Command Set Notes 7 10 510201 8 ERASE 19h Bit 7 6 5 4 3 2 1 0 Byte 00 0 0 0 1 1 0 0 1
255. power on or after the EXB 8500 is reset by a SCSI bus reset or a Bus Device Reset message Changes in the SCSI ID setting will not take effect until one of these conditions occurs Note The logical unit number LUN of the EXB 8500 is 0 and cannot be changed You can use any one of the following methods to set the SCSI ID m Set the DIP switches on the rear of the EXB 8500 m Connectaremote switch to the remote connector on the back of the EXB 8500 m Attach jumpers shunts to the pins on the remote connector Jumpers are provided with the EXB 8500 These methods are explained in the following sections Important If you are using a remote switch or jumpers to set the SCSI ID make sure that the DIP switches are set to address 0 Similarly if you are using the DIP switches to set the SCSI ID make sure that the remote switch or jumpers are set to address 0 If you set both the DIP switches and the remote switch to a particular address the actual SCSI ID will be the logical OR of the two settings For example if the remote switch is set for address 1 and the DIP switches are set for address 2 the actual SCSI ID will be 3 December 1991 2 3 2 Installing the EXB 8500 Setting the SCSI ID with the DIP Switches To set the SCSI ID with the DIP switches on the EXB 8500 follow these step 1 S Locate the DIP switches labeled U2 on the back of the EXB 8500 as shown in Figure 2 1
256. r List Heade uuu nce Rcs doe ee 13 8 Field Definitions 5 2 448 se ar qupd y EE a PU DR dox 13 8 13 3 Block DeSCUHDIOF o sise FOROR EROS 13 11 Field DenmiVions E Wo 9n RC pa ESS 13 11 13 4 Vendor Unique Parameters o o Rm 13 15 Field Definitions oss cc so 3 R9 o9 13 15 13 5 Read Write Error Recovery Page iud os ed BY OO 13 19 Fi ld Definitions snena ue a eek we Brad 13 19 13 6 Disconnect Reconnect Page 2 2 22 be Shee ew mmm 13 21 Field Definitions x ss se 4 4 eux RR EORR X aaa Box 13 21 13 7 Data Compression Page 2 4 5 554524 oH Ee 13 23 Field Definitions quo tx ee A more 13 23 13 8 Device Configuration Page 5 oy Rew RR 13 25 Field curs rer arae x Sand SB XR ES NUR 13 25 13 9 Vendor Unique Parameters Pagel 2 22245 ccs rn 13 29 Field Definitions v 13 29 13 10 Vendor Unique Parameters Page 2 13 34 Field Definitions aac uoo om X o 99 939 X 3 43 x TEESE S 13 34 14 PREVENT ALLOW MEDIUM REMOVAL 14 1 Field Pennines s vas xu 565979 PUE GRE AR Y X o PS XS 14 1 15 READ 08h 226 ee ee ek ee ee we ce 15 1 19 Field Defimitons oa at Re Ve o EP WO
257. r configuration Figure 2 4 shows how to position the jumpers for addresses 0 through 7 Figure 2 4 Jumper Connections for the EXB 8500 s SCSI ID 2 4 Attaching the EXB 8500 to a Frame The procedure you use to attach the EXB 8500 to a mounting frame or bracket depends on the requirements of your installation The main housing of the EXB 8500 includes two sets of mounting holes one set on the sides and one set on the bottom to allow for a number of mounting positions These mounting holes accommodate 76 32 screws and are designed for standard 5 25 inch form factor mounting requirements December 1991 2 7 2 Installing the EXB 8500 The EXB 8500 can be mounted either horizontally or vertically and in a stationary or sliding position When the EXB 8500 is mounted horizontally the door opens down from the top When the EXB 8500 is mounted vertically the door can open to the left or right When mounting the EXB 8500 follow these guidelines m Use either the four mounting holes on the sides of the EXB 8500 shown as A in Figure 2 5 or the four mounting holes on the bottom SYS card cover of the EXB 8500 shown as in Figure 2 6 To ensure that the EXB 8500 is securely mounted and that the chassis is not subject to distortion use all four holes in whichever set you choose m Do not obstruct the ventilation slots on the sides and top of the device This ensures that the EXB 8500 can be adequately cooled SS A
258. r during a buffered write operation before that data is written to the tape The value is expressed in 4 KByte increments The default value for this byte is 80h 512 KBytes Valid values range from 20h to DOh 128 to 832 KBytes Byte 05 Read Buffer Empty Ratio The Read Buffer Empty Ratio represents how empty the buffer must be during a buffered read operation before additional data will be read from the tape The value is expressed in 4 KByte increments The default value for this byte is 80h 512 KBytes Valid values range from 20h to DOh 128 to 832 KBytes The Read Buffer Empty Ratio must equal the Write Buffer Full Ratio If these values are not equal the EXB 8500 returns Check Condition status with the sense key set to Illegal Request 5h Note The Write Buffer Full Ratio and the Read Buffer Empty Ratio in the Device Configuration Page have the same function as the Motion Threshold in the Vendor Unique Parameters Page 1 If both pages are sent the value that is received last by the EXB 8500 takes precedence Bytes 06 and 07 Write Delay Time If a WRITE command completes without transferring enough data to exceed the value specified for the Write Buffer Full Ratio the value specified by the Write Delay Time field is used to determine the maximum amount of time in units of 100 msec that the data will remain in the buffer When the time specified by Write Delay Time elapses the data in the buffer is automatically written to
259. r of Blocks in Buffer field 15 not valid for the EXB 8500 The value returned for this field is 0 Bytes 16 through 19 Number of Bytes in Buffer The Number of Bytes in Buffer field is not valid for the EXB 8500 The value returned for this field is 0 18 3 18 READ POSITION 34h Notes 18 4 510201 19 RECEIVE DIAGNOSTIC RESULTS 1 Bit 7 6 5 4 3 2 1 0 Byte 00 0 0 0 1 1 1 0 0 01 Logical Unit Number Reserved 02 Reserved 03 MSB Allocation Length 04 LSB 05 TD VU Reserved 0 0 You can use the RECEIVE DIAGNOSTIC RESULTS command for either of the following purposes m Obtaining the results of the tests requested by a previous SEND DIAGNOSTIC 1Dh command or m Obtaining a trace of SCSI and servo command activity for the EXB 8500 Note To ensure that the diagnostic results are up to date and accurate be sure that the RECEIVE DIAGNOSTIC RESULTS command immediately follows the SEND DIAGNOSTIC command and that the EXB 8500 is reserved for the initiator s exclusive use As described in this chapter the bit and byte settings for the RECEIVE DIAGNOSTIC RESULTS command descriptor block depend on whether you are using the command to obtain diagnostic results data or command trace data December 1991 19 1 19 RECEIVE DIAGNOSTIC RESULTS 1 19 1 Field Definitions Bytes 03 and 04 Allocation Length The Allocat
260. rack Block Track Block P5 15 199AAh CCD50h 21ECh 10F60h P5 30 31D10h 18E880h 22B3h 11598h is P5 60 623DAh 311EDOh 25D0h 12E80h P5 90 93568h 49AB40h 22A2h 11510h P6 15 11888h 8C440h 954h AAAOh P6 30 23052h 118290h 1F71h FB88h P6 P6 60 45FE4h 22FF20h 229Eh 114F0h P6 90 68F78h 347BCOh 2452h 12290h P6 120 45F840h 233Bh 119D8h P5 15 199AAh CCD50h 21ECh 10F60h P5 30 31D10h 18E880h 22B3h 11598h P6 15 11888h 8C440h 954h AAAOh PI P6 30 23052h 118290h 1F71h FB88h P6 60 45FE4h 22FF20h 229Eh 114F0h P6 90 P5 60 623DAh 311EDOh 25D0h 12E80h P6 120 P5 90 8BFO8h 45F840h 233Bh 119D8h Track and block counts from LEOT to PEOT are approximate As described in this section the EXB 8500 can accurately determine the lengths of these tape sizes at LBOT C 6 510201 Table 4 Track and Physical Block Counts for EXB 8200 Format Appendix C Data Cartridge Capacities Cartridge Cartridge LBOT to LEOT LEOT to PEOT Type Size Track Block Track Block P5 15 CCD5h 666A8h 10F5h 87A8h P5 30 18E88h C7440h 1159h 8AC8h P5 60 311EDh 188F68h 12E7h 9738h P5 90 49AB4h 24D5A0h 1150h 8A80h P6 15 8C44h 46220h 11A9h 8D48h P6 30 11829h 8C148h FB8h 7DCOh P6 P6 60 22FF2h 117F90h 114Eh 8A70h P6 90 347BCh 1A3DEOh 1228h 9140h P6 120 45F84h 22FC20h 119Dh 8CE8h P5 15 CCD5h 666A8h 10F5h 87A8h P6 60 22FF2h 117F90h 114Eh 8A70h P5 30 18E88h C7440h 1159h 8AC8h PI P6 15 8C44h 46220h 11A9h 8D48h P6 30 11829h 8C148h FB8h 7DCOh P6 90 P5 6
261. ritten tape the EXB 8500 automatically determines the tape s format for you Appending Data to a Previously Written Tape If the tape is in EXB 8500 format new data can be appended to existing data if the tape is positioned on either side of a long filemark or at the end of data mark If the tape is in EXB 8200 format new data can be appended to existing data if the tape is positioned at the beginning of tape side of a long filemark or at the end of data blank tape EXB 8500 Format Compared to EXB 8200 Format This section highlights the differences between EXB 8500 format and EXB 8200 format For detailed information about EXB 8500 recording format and recording parameters refer to the EXB 5500 68mm Cartridge Tape Subsystem Product Specification For detailed information about EXB 8200 recording format and recording parameters refer to the EXB 8200 8mm Cartridge Tape Subsystem Product Specification Track Structure EXB 8500 Format When writing data in EXB 8500 format the EXB 8500 uses its two write heads W1 and W2 to write two partially overlapping physical tracks to the tape during the first 180 degree rotation of the drum The two read heads R1 and R2 perform the read after write operation during the second 180 degree rotation of the drum December 1991 3 3 3 Operating the EXB 8500 3 4 When reading data written in EXB 8500 format the EXB 8500 uses its two read heads R1 and R2 to read the two partially overlapping ph
262. rmat For this reason the reconnect threshold for EXB 8200 write operations is expressed in 1 KByte increments When the reconnect threshold value is exceeded the EXB 8500 reconnects to the initiator and data transfer continues The data transfer from the initiator continues until the buffer is full or until the initiator has no more data to write Then the EXB 8500 disconnects from the initiator but continues to transfer data from the buffer to the tape until the buffer is empty 3 8 510201 3 Operating the EXB 8500 Streaming Read Operation In a streaming read operation the buffer to initiator transfer rate is equal to or greater than the tape to buffer transfer rate that is data transfers to the initiator occur at 500 KBytes per second or faster In this mode of operation the EXB 8500 disconnects from the initiator when the buffer becomes empty but continues to read data from the tape The reconnect threshold value represents the minimum amount of data in 4 KByte increments that must be in the EXB 8500 s 1 MByte buffer before the EXB 8500 will reconnect to the initiator to transfer data from the buffer When the reconnect threshold value is exceeded the EXB 8500 reconnects to the initiator and data transfer resumes The data transfer to the initiator continues until the buffer is empty Then the EXB 8500 disconnects from the initiator but continues to transfer data from the tape to the buffer Summary of Motion and Reconnect
263. roducts gt Refer to Table C 3 and Table C 4 for detailed information about data cartridge capacities C 8 510201 Appendix D Sense Key Information December 1991 This appendix lists the possible combinations of values for the Additional Sense Code ASC and the Additional Sense Code Qualifier ASCQ fields in the Extended Sense Bytes returned by the REQUEST SENSE 03h command It correlates each ASC and ASCQ combination with one or more of the EXABYTE unique Fault Symptom Codes FSC that are returned as byte 28 in the Extended Sense Bytes Note For more information about the FSCs listed refer to Appendix E Appendix E also describes the recommended error recovery procedures for each Fault Symptom Code For ease of reference the information in this appendix is listed in numerical order for each sense key byte 2 bits 3 through 0 D 1 Appendix D Sense Key Information Sense Key 0h No Sense ASC ASCQ Related Byte 12 Byte 13 FSC 00h 00h No additional sense information 06h OAh A filemark was encountered during a read space or locate ooh om operation The tape is positioned at the EOT side of the filemark pee LEOT was encountered during a read write or write filemarks 04h 00h 02h operation 09h 28h 00h 04h PBOT was encountered during a space or locate operation 35h Sense Key 2h Not Ready ASC ASCQ Related
264. ror to attempt a read operation 10h Bh 11 The read operation was aborted as requested 11h 3h 13 Too many permanent read errors can t sync 14h 3h 11 PEOT was encountered during a read operation 15h 9h 3 An invalid file number was detected in a filemark during a read operation 16h 3h 13 A Medium Error was detected during a read operation 17h 4h 8 3 12 A Hardware Error was detected during a read operation The data on the tape is compressed but the hardware cannot 1Ch 3h 14 decompress it Note This fault symptom code is include for upward compatibility with products supporting data compression 26h 5h 11 A WRITE FILEMARKS command was received when the tape was not at a legal position to write 27h 7h 5 A WRITE FILEMARKS command was received when the data cartridge was write protected 28h Oh 11 LEOT was encountered during or before the write filemarks operation the filemark was written 32h Oh 11 A filemark was detected during a space or locate operation E 2 510201 Appendix E Fault Symptom Codes FSC SK Description 33h 8h 11 EOD was encountered during a space or locate operation 34h 3h 11 PEOT was encountered during a space or locate operation 35h Oh 13 PBOT was encountered during a space or locate operation 36h 3h 13 A tape format error was encountered during a space or locate operati
265. rtridge is already loaded and there is data in the write buffer the data is written 1 T to the tape before performing the operation Note If the tape is already loaded positioned at LBOT and there is no data in buffer no tape motion occurs The door is opened even if the PREVENT ALLOW MEDIUM REMOVAL command was issued with the Prevent bit set to 1 gt The unload operation is performed even if the PREVENT ALLOW MEDIUM REMOVAL command was issued with the Prevent bit set to 1 however the data cartridge is not ejected from the EXB 8500 Byte 05 Bits 7 and 6 Vendor Unique There are no vendor unique definitions for this command 10 3 10 LOAD UNLOAD 1Bh Notes 10 4 510201 11 LOCATE 2Bh Bit 7 6 5 4 3 2 1 0 Byte 00 0 0 1 0 1 0 1 1 01 Logical Unit Number Reserved BT GP Immed 02 Reserved 03 MSB ES Block Address 05 06 LSB 07 Reserved 08 Partition 09 ADE VU Reserved 0 0 The LOCATE command causes the EXB 8500 to position the tape at the specified logical position The LOCATE command is not supported for tapes written in EXB 8200 format and will result in Check Condition status The sense key will be set to Illegal Request 5h Notes m If the disconnect option is enabled the EXB 8500 can disconnect from December 1991 the initiator while the LOCATE command is executing If a LOCATE
266. rtridge loaded the value is 0 Byte 26 Tracking Retry Counter The Tracking Retry Counter field increments when a tracking error occurs during tape motion start up This counter is reset to O after any of the following m A REQUEST SENSE command is issued with the CLRCNT bit byte 05 bit 7 set to 1 Note that in order for the reset to be performed 29 1Dh bytes of sense data must be read by the REQUEST SENSE command m The tape is loaded or rewound m The mode changes from write to read or from read to write m The EXB 8500 is reset December 1991 21 9 21 REQUEST SENSE 03h Byte 27 Read Write Retry Counter The Read Write Retry Counter field increments whenever a read or write operation is unsuccessful and a recovery retry action is performed The counter is reset to 0 after any of the following m A REQUEST SENSE command is issued with the CLRCNT bit byte 05 bit 7 set to 1 Note that in order for the reset to be performed 29 1Dh bytes of sense data must be read by the REQUEST SENSE command m The tape is loaded or rewound m The mode changes from write to read or from read to write m The EXB 8500 is reset Byte 28 Fault Symptom Code The Fault Symptom Code field is an EXABYTE unique byte used to indicate the specific nature of hardware and software errors or other events Appendix E lists the errors indicated by the Fault Symptom Code byte Note The Fault Symptom Code field can also be used to determine th
267. ry Data s s 63244244 644282254 deen s 9 3 Field Definitions v a soe a die ee ee et ee ee Sw 9 4 9 3 Vital Product Data Pave ss o sod sacre d hop Sc IE A Wo 9 7 Piel Def eu 2 a Rh eek Bae SS Red SR EE Bok ERA ded 9 7 94 Unit Serial Number Pape 45 22 ee ee eh eves 9 8 5 oe ole ee Oe ee Rw 8 9 8 December 1991 ix 10 LOAD UNLOAD IBh oom OR ERROR 10 1 10 1 Field 6 2 24 UON He Ga whe eo Ya ee Be SE 10 1 11 LOCATE 280 E 11 1 LIT Feld EeBnttols eov ow HS 11 2 11 2 Exceptions and Error Conditions 2 22 6483408 ee 4 11 4 EOD Detected gris a dew bul de qd eS 11 4 PEOT acs s a acti oat g oa k OR GS eke me Eos uds 11 4 Locating Past the Last Data or Filemark 11 4 Unrecoyerable Error s s sa d sda Go eee eee ee SR ak 4 eed Bs 11 5 Illegal Requests s io 9699 poo GR oe EWES ESS EELS 11 5 12 MODE SELECT 15H eae ee ee ee ee 12 1 12 1 Field Defmniuols iul aem eee ease B RO a Pie 0534 12 1 2 2 Parameter List Header ode oe le 12 7 Field Definitions ue xu beg Rok OE S 0 xo 0X 12 7 12 3 Block Descriptor lt se gore B SECURE QR Se Pu ege S 12 9 Field Definitions gt
268. s 3 11 control byte format of 7 3 Index D data cartridges capacities of C 1 C 8 capacity of EXATAPE cartridges 8 effect of changing 6 38 effect of on reset 6 41 loading into EXB 8500 3 15 time required to load 3 16 time required to unload 3 20 track and block counts EXB 8200 format 7 track and block counts EXB 8500 format 6 write protect switch 3 14 Data In phase information command 6 30 READ command 6 28 Data Out phase information commands 6 26 WRITE command 6 24 Data Protect 7h sense key D 6 Density Code field MODE SELECT command 12 9 MODE SENSE command 13 11 Device Configuration Page MODE SELECT command 12 24 MODE SENSE command 13 25 Diagnostic Page 19 3 diagnostic tests SEND DIAGNOSTIC command 24 3 differential SCSI cable requirements for A 4 installation procedure for 2 11 pin assignments for cable connector A 5 terminators 2 1 DIP switches for setting SCSI ID 2 4 directory support 3 10 B 1 B 10 Disconnect 04h message 6 7 Disconnect Reconnect Page MODE SELECT command 12 19 MODE SENSE command 13 21 dump See memory dump See trace dump E EBD bit MODE SELECT command 12 14 12 31 MODE SENSE command 13 16 13 31 EEPROM image options directory support 3 10 B 1 B 10 even byte disconnect 12 14 12 31 tape motion command handling 3 15 6 42 unload button 3 16 end of data mark See EOD environmental requirements for shipping the EXB 8500 4 5 EOD described for EXB 8500 format 3 6 d
269. s 7 through 5 Peripheral Qualifier This field in combination with the Peripheral Device Type field byte 00 bits 4 through 0 identifies the device currently connected to the logical unit The value returned for this field is 0 which indicates that the specified device is currently connected to the selected logical unit If the LUN in the CDB or in the Identify message 15 not O the value returned for these fields is 7Fh which indicates that the LUN is invalid Byte 00 Bits 4 through 0 Peripheral Device Type This field in combination with the Peripheral Qualifier field byte 00 bits 7 through 5 identifies the device currently connected to the logical unit The value returned for this field is Olh which identifies the EXB 8500 as a sequential access device If the LUN in the CDB or in the Identify message is not 0 the value returned these fields is 7Fh which indicates that the LUN is invalid Byte 01 Bit 7 RMB The value returned for this field 15 1 which indicates that the media 15 removable Byte 01 Bits 6 through 0 Device Type Modifier The value returned for this field is which indicates that there are no vendor specific qualification codes Byte 02 Bits 7 and 6 ISO Version The value returned for this field is Oh which indicates that the EXB 8500 does not claim compliance with the ISO standards Byte 02 Bits 5 through 3 ECMA Version The value returned for this field is Oh which indicates that the EXB
270. s and screwdriver if needed to attach the EXB 8500 to a mounting frame Flat nose wiring pliers if the EXB 8500 will not terminate the SCSI bus 14 inch female spade connector or an M3 0 5 x 6 mm self tapping screw if an additional chassis ground is desired 2 2 Unpacking the EXB 8500 To unpack the EXB 8500 follow these steps 1 2 Place the shipping carton on flat level surface Remove the adhesive tape from the top of the carton and open the carton flaps Carefully remove the packing material from the top of the EXB 8500 Holding the bottom edges of the EXB 8500 lift it out of the carton and place it on a flat level surface Check the contents of the carton against the packing list and inspect the EXB 8500 for possible damage If a part is missing or the EXB 8500 15 damaged notify the carrier and your vendor immediately Let the EXB 8500 acclimate to the operating environment for at least two hours before applying power Note If the EXB 8500 has been stored for more than six months follow 2 2 the instructions in Section 2 7 when applying power for the first time 510201 2 Installing the EXB 8500 2 3 Setting the SCSI ID After you have unpacked the EXB 8500 you can set the SCSI ID When you set the SCSI ID you select the address to be asserted by the EXB 8500 during arbitration You can select addresses 0 through 7 for the EXB 8500 The EXB 8500 sets its SCSI ID internally following normal
271. s the total number of bytes of MODE SENSE parameter data available to be transferred excluding this byte The value returned for this field is 03h plus the number of bytes of parameter data to be returned based on the field settings in the CDB 510201 Byte 01 Medium Type 13 MODE SENSE 1Ah The value returned in the Medium Type byte represents the type of data cartridge currently loaded in the EXB 8500 The values that can be returned are shown in Table 13 4 Table 13 4 Values Returned for Medium Type Byte in MODE SENSE Data Value Returned EL punt P EXATAPE Equivalent 00h None Cih P5 15 C2h P5 30 C3h 5 60 C4h P5 90 112m 8th P6 15 15m 82h P6 30 83h P6 60 54m 84h P6 90 85h P6 120 As described in Appendix C the EXB 8500 initially uses the settings of the CT and P5 bits in the MODE SELECT command to autosize P5 60 P5 90 P6 90 and P6 120 tapes The EXB 8500 accurately resizes these longer length tapes as the tape position approaches LEOT For this reason if the CT and P5 bits are incorrectly set the value returned for the Medium Type byte may change when the tape is resized Byte 02 Bit 7 WP The Write Protect bit indicates if the data cartridge loaded in the EXB 8500 is write protected This bit is defined as follows 0 The data cartridge loaded in the EXB 8500 is not write protected 1 The data cartridge loaded in the EXB 8500 is
272. s to this revision refer to page iv 510201 Product Warranty Caution The EXB 8500 8mm Cartridge Tape Subsystem CTS is warranted to be free from defects in materials parts and workmanship and will conform to the current product specification upon delivery For the specific details of your warranty refer to your sales contract or contact the company from which the EXB 8500 was purchased The warranty for the EXB 8500 shall not apply to failures of any unit when m The EXB 8500 is repaired by anyone other than the Manufacturer s personnel or approved agent m The EXB 8500 is physically abused or is used in a manner that is inconsistent with the operating instructions or product specification defined by the Manufacturer m The EXB 8500 fails because of accident misuse abuse neglect mishandling misapplication alteration faulty installation modification or service by anyone other than the factory service center or its approved agent m The EXB 8500 is repaired by anyone including an approved agent in a manner that is contrary to the maintenance or installation instructions supplied by the Manufacturer m The Manufacturer s serial number tag is removed m The EXB 8500 is damaged because of improper packaging on return CAUTION Returning the EXB 8500 in unauthorized packaging may damage the unit and void the warranty If you are returning the EXB 8500 for repair package it in its original packaging or in replacement pa
273. sconnect from the initiator during the data transfer phase The EXB 8500 will not disconnect during the data transfer phase The power on default for the ND bit is 0 Restrictions when the ND bit is 0 The maximum logical block size allowed in fixed or variable mode is 240 KBytes 3C000h Restrictions when the ND bit is 1 If the logical block size specified by the Block Length field in the Block Descriptor is greater than 160 KBytes 28000h setting the ND bit to 1 causes the EXB 8500 to return Check Condition status with the sense key set to Illegal Request 5h The total number of bytes that can be transferred as a result of a single WRITE or READ command in fixed or variable mode is 160 KBytes 28000h That is the total transfer length specified by the CDB must be 160 KBytes or less During a write operation the data transfer from the initiator does not start until the number of bytes of available space in the EXB 8500 s buffer is greater than or equal to the total transfer length specified by the CDB During a read operation the data transfer to the initiator does not start until all of the data requested by the CDB up to a total transfer length of 160 KBytes is resident in the EXB 8500 s buffer If the Buffer Full Ratio and Buffer Empty Ratio see Section 12 6 are set to values less than AOh or greater than COh they will be changed to AOh This is necessary for proper buffer management The Maximum Burs
274. se cse mU eS Fa E Rede due amp ds X CRUS 12 9 12 4 Vendor Unique Parameters 25 22 RR 12 12 Field Definitions s mpra ted Ge m Cg Sew A 12 12 12 5 Read Wnite Error Recovery Page 2 22 22 o n 12 17 Field Definitions 2 sse a soe aa Xo 39 X eR RU 8 EDAD E a 12 17 12 6 Discomect Reconnect Page yay ee eee om x EE on 12 19 unb ACC 12 19 12 7 Data Compression Page amp suo obe ox Sade SX Ye Po 12 22 Field Definitions s s 9 Osa en cM CUR ed 12 22 12 8 Device Configuration Page uuu hg gh gre ex RCRUM 12 24 Field DeftniUODS e 5 644 624 a OR 46 Foe oe s 12 24 12 9 Vendor Unique Parameters Page L cR ETE 12 29 Field Definitions qe Se AE Sa ge od 12 29 12 10 Vendor Unique Parameters Page 2 som Res 12 34 Field lt s 4 66 584 beeen oe 3 3 x See OES 12 34 12 11 Exceptions and Error Conditions 9x ERES 12 35 Ilegal Value in MODE SELECT Data 22 201444444448 a4 12 35 12 12 Tape Format Examples ca co GS 3 993 4 ERR RE 12 36 Writing and Reading in EXB 8200 Format 12 36 Writing and Reading in EXB 8500 Format 12 38 If You Cannot Issue MODE SELECT Commands 12 40 X 510201 13 MODE SENSE e 13 1 Field Definitions 46 9 3 39 94 8 Oe Re 13 2 13 2 Paramete
275. set by the next command execution that is not an INQUIRY or REQUEST SENSE command for the same initiator m Error information is reset by a power on reset a Bus Device Reset message or a SCSI bus reset condition 21 11 21 REQUEST SENSE 03h Notes 21 12 510201 22 RESERVE UNIT 16h Bit 7 6 5 4 3 2 1 0 Byte 00 0 0 0 1 0 1 1 0 01 Logical Unit No 3rdPty Third Party Dev ID RSVD 02 03 Reserved 04 05 Vendor Unique Reserved 0 0 The RESERVE UNIT command reserves the EXB 8500 for an initiator s exclusive use or if third party reservations are in effect for another SCSI device s use The reservation remains in effect until a RELEASE UNIT 17h command is received from the same initiator or until the EXB 8500 is reset by a SCSI bus reset a Bus Device Reset message or a power on reset It is not an error for the initiator that made the last reservation to send another identical RESERVE UNIT command If the EXB 8500 is reserved and any command other than an INQUIRY 12h or a REQUEST SENSE 03h command is received from another initiator the command will not be honored Reservation Conflict 18h status is returned to the initiator that sent the command 22 1 Field Definitions Byte 01 Bit 4 3rdPty The 3rdPty bit is used to request third party reservations as follows 0 A third party reservation is not requested 1 A third p
276. set to 1 and the block length in the MODE SELECT command is 0 m The Fixed bit is set to 1 and the SILI bit is set to 1 m The tape is in an invalid position to perform a read operation a READ command was issued after a WRITE or WRITE FILEMARKS command m The EXB 8500 is not ready or no data cartridge is loaded December 1991 15 7 15 READ 08h Notes 15 8 510201 16 READ BLOCK LIMITS 05h Bit 7 6 5 4 3 2 1 0 Byte 00 0 0 0 0 0 1 0 1 01 Logical Unit Number Reserved 02 03 Reserved 04 05 Vendor Unique Reserved 0 0 16 1 Field Definitions The READ BLOCK LIMITS command requests that the EXB 8500 return data identifying the maximum and minimum logical block lengths supported The data returned by the READ BLOCK LIMITS command applies to both the variable and fixed block lengths for the READ and WRITE commands Byte 05 Bits 7 and 6 Vendor Unique There are no vendor unique definitions for this command December 1991 16 1 16 READ BLOCK LIMITS 05h 16 2 Read Block Limits Data Bit 7 6 5 4 3 2 1 0 Byte 00 Reserved 01 MSB 02 Maximum Block Length 03 LSB 04 MSB 2 Minimum Block Length 05 LSB The READ BLOCK LIMITS command returns to the initiator the maximum and minimum block lengths supported by the EXB 8500 The field definitions are as follows
277. sful reception of data The value represents the number of 4 nanosecond increments allowed for the synchronous transfer period The EXB 8500 supports a minimum of 62 increments or 250 nanoseconds for the minimum synchronous transfer period Byte 04 REQ ACK Offset This byte identifies the maximum number of REQ pulses that can be outstanding before the leading edge of the corresponding ACK is received by the EXB 8500 The EXB 8500 allows up to 12 outstanding REQ pulses 6 5 6 SCSI Physical Path Communications 6 6 The Synchronous Data Transfer Request message is used to negotiate synchronous data transfer agreements If the initiator wants to transfer data synchronously it must negotiate a synchronous data transfer agreement before transferring data Note The EXB 8500 will not originate a synchronous data transfer request However it sends a Synchronous Data Transfer Request message in response to the initiator s request A negotiation for synchronous data transfer is accomplished as follows 1 The initiator sends a Synchronous Data Transfer Request message to the EXB 8500 This message specifies a transfer period and a REQ ACK offset 2 The EXB 8500 returns a Synchronous Data Transfer Request message The transfer period returned by the EXB 8500 will be equal to or greater than the initiator s value and the REQ ACK offset will be less than or equal to the initiator s value Once negotiated the synchronous transfer agreement
278. sing the Identify message the EXB 8500 will accept and process messages from the initiator whenever the Attention signal is driven true The EXB 8500 will respond to the Attention signal for each SCSI bus phase as described in Table 6 2 Table 6 2 EXB 8500 Responses to Attention Signal If the initiator asserts the Attention signal during this The EXB 8500 responds phase Selection Immediately following the selection Command At the end of the phase after all CDB bytes have been received Data In After the next byte has been received by the initiator Data Out After the next byte has been received by the EXB 8500 Status After the Status byte has been received by the initiator Message In After the next message byte has been received by the initiator Message Out After the next message byte has been received by the EXB 8500 will stay in Message Out phase 6 12 510201 6 SCSI Physical Path Communications Message Processing after the Selection Phase Figure 6 1 shows that the EXB 8500 will only accept three legal messages immediately after the Selection phase Abort Reset and Identify Parity Error in the Selection Phase When parity checking is enabled and the EXB 8500 detects a parity error during the Selection phase it stays in the Message Out phase until the Attention signal goes low Then it retries by going to the Message Out phase again December 19
279. st data on tape The EOD mark is automatically written when the EXB 8500 receives one of the following commands after completing a WRITE or WRITE FILEMARKS operation LOAD UNLOAD 1Bh LOCATE 2Bh in the reverse direction REWIND 01h SPACE 11h in either direction The EOD mark is overwritten when additional data is written to tape Note 3 6 The EOD mark is not used for EXB 8200 format 510201 3 Operating the EXB 8500 3 2 Streaming and Start Stop Modes The EXB 8500 includes a 1 MByte data buffer that enables it to operate as either a streaming tape device or as a start stop tape device The mode of operation depends on the rate that data can be transferred between the initiator and the EXB 8500 If the initiator can sustain a minimum transfer rate of 500 KBytes per second the EXB 8500 operates in streaming mode If the initiator cannot sustain this transfer rate the EXB 8500 starts and stops the tape automatically In start stop mode the motion threshold can be used to fine tune the starting and stopping of tape motion In streaming mode the reconnect threshold can be used to fine tune the rate of disconnects and reconnects between the EXB 8500 and the initiator Motion Threshold The motion threshold is used in start stop mode to control data transfers between the buffer and the tape The motion threshold is measured in 4 KByte increments The default value for motion threshold is 80h 512 KBytes this value can
280. t Serial Number Page Bit 7 6 5 4 3 2 1 0 Byte 00 Device Type Code 01 Page Code 02 Reserved 03 Page Length 04 Unit Serial Number 13 9 8 Field Definitions Byte 00 Device Type Code The value returned for this field is OI h which identifies the EXB 8500 as a sequential access device If the LUN in the CDB is not 0 the value returned is 7Fh which indicates that the LUN is invalid Byte 01 Page Code The value returned for this field is 80h which is the Page Code for the Unit Serial Number page Byte 03 Page Length The value returned for this field 15 OAh which is the number of additional bytes available to be transferred excluding this byte Bytes 04 through 13 Unit Serial Number The value returned for this field is the actual serial number of the EXB 8500 as listed on the serial number label The MSB is contained in byte 04 Serial numbers of less than 10 characters contain trailing blanks 20h 510201 10 LOAD UNLOAD 1Bh Bit 7 6 5 4 3 2 1 0 Byte 00 0 0 0 1 1 0 1 1 01 Logical Unit Number Reserved Immed 02 Reserved 03 04 Reserved Re Ten Load 05 Vendor Unique Reserved 0 0 The LOAD UNLOAD command causes the EXB 8500 to load or unload a data cartridge Loading a data cartridge involves the following 1 Loading the tape in the tape path 2 Posi
281. t Size field see Section 12 6 has precedence over the ND bit For this reason if the Maximum Burst Size has already been set to a non zero value attempting to set the ND bit to 1 causes the EXB 8500 to return Check Condition status with the sense key set to Illegal Request The ASC will be set to 1 Ah Byte 02 Bit 4 RSVD This bit is reserved 12 30 510201 12 MODE SELECT 15h Byte 02 Bit 3 NBE No Busy Enable This bit is included for EXB 8200 compatibility only This bit is set to 1 in the MODE SENSE data and is ignored by the MODE SELECT command Byte 02 Bit 2 EBD Even Byte Disconnect This bit is used to enable disconnects on even byte boundaries Two options are available from EXABYTE to control what happens when the EBD bit is set to 1 Depending on EXB 8500 s EEPROM image setting the EBD bit to 1 allows disconnects to occur on two byte boundaries or on four byte boundaries 0 Disconnect on any byte 1 Disconnect on even byte two byte or four byte boundaries Notes m If the logical block length specified by the Block Length field in the Block Descriptor is not divisible by 4 or 2 if the EEPROM image is set for two byte boundary disconnect setting the EBD bit to 1 causes the EXB 8500 to return Check Condition status with the sense key set to Illegal Request 5h m For information about changing the power on default for even byte disconnect refer to Section 3 4 Byte 02 Bit 1 PE Parity Ena
282. t be ejected One of the following messages is displayed in the CTS Monitor program E Can t write on tape tape is write protected B Can t start operation until self test and autoload are done o Hardware must be upgraded to support this operation Press the unload button to eject the tape and restore normal EXB 8500 operation Then reset the EXB 8500 wait until it is idle and restart the process with a new 15m tape 5 5 5 Loading New Microcode from Tape 5 6 Time Required to Make a Microcode Update Tape As shown in Table 5 2 approximately two minutes are required to make a microcode update tape not including the time required to rewind unload and eject any tape present in the EXB 8500 before the new tape is inserted Table 5 2 Time Required to Make a Microcode Update Tape Step Time required seconds Load new tape 35 Copy code memories to buffer 5 Validate image in buffer 19 Write buffered data to tape 44 Unload and eject tape 18 TOTAL 121 approx 510201 Part 2 SCSI Commands for the EXB 8500 6 SCSI Physical Path Communications December 1991 This chapter describes the following aspects of SCSI physical path communications for the EXB 8500 How the EXB 8500 processes SCSI bus messages How the EXB 8500 recovers from SCSI bus errors How the EXB 8500 processes the Unit Attention condition How the EXB 8500 handles different types of resets Note The ANSI Small Computer System Interf
283. t can be set to any value between 00h and OBh The default value for this field is OBh Note X Before you read a tape that may have been written without retries issue a MODE SENSE command and check the value returned for the WWR bit in the Vendor Unique Parameters Page 2 If the WWR bit is set to 1 specify O for this field otherwise specify a non zero value You can disable write retries by setting the Write Retry Count field to 0 at LBOT Bytes 04 through 07 Reserved These bytes are reserved Byte 08 Write Retry Count The Write Retry Count field specifies how many times the EXB 8500 should rewrite a physical block before an unrecoverable write error is reported The value for this field can only be changed when the tape is positioned at LBOT The valid values for this field are 00h and OBh The default value is OBh Specify 0 for this field to set the Write Retry Count to Specify any other nonzero value to set the Write Retry Count to OBh A value of 0 for the Write Retry Count indicates that the EXB 8500 will not rewrite any physical blocks during a write operation and will continue to write additional data If this value is used the EXB 8500 may not be able to recover the data written on the tape since its write integrity cannot be guaranteed Note If this field was set to O0h when the tape was written WWR field in the MODE SENSE Vendor Unique Parameters Page 2 will be set to 1 12 18 510201 12 6 Disco
284. t in the MODE SENSE command indicates that the EXB 8500 is writing in EXB 8500 format 000b Reading EXB 8500 Format Tapes To use the EXB 8500 to read an EXB 8500 format tape follow these steps 1 Load the data cartridge in the EXB 8500 2 Issue a READ command to read the data The EXB 8500 automatically determines the tape s format 12 39 12 MODE SELECT 15h If You Cannot Issue MODE SELECT Commands This section describes how to write tapes in different formats if you cannot issue MODE SELECT commands to set the Density Code 1 Obtain a tape that has already been written in the desired format that is either in EXB 8200 format or in EXB 8500 format This tape must include an LBOT pattern plus data or at least one filemark 2 Load the previously written tape in the EXB 8500 3 Issue a SPACE or READ command to move the tape away from LBOT The EXB 8500 automatically sets the Density Code to 14h for EXB 8200 format tapes or to 15h for EXB 8500 format tapes 4 Issue a WRITE or WRITE FILEMARKS command to write data or a filemark Note After you complete steps 2 3 and 4 the Density Code remains 14h for EXB 8200 format tapes or 15h for EXB 8500 format tapes for as long as that tape is loaded 5 Rewind the tape to LBOT 6 Issue a WRITE or WRITE FILEMARKS command to write data or a filemark to the tape and to overwrite the existing data or filemark The tape will be written in desired format 7 To c
285. t the Buffer Full Ratio to a value less than AOh or greater than COh the value will automatically be changed to AOh If however you set the Buffer Full Ratio to a value between AOh and COh that value will take effect If the ND bit is 0 the Buffer Full Ratio can have any value from 20h to DOh 128 to 832 KBytes Byte 03 Buffer Empty Ratio The Buffer Empty Ratio represents how empty the buffer must be during a buffered write operation before the EXB 8500 will attempt to reconnect to the initiator The value is expressed in 4 KByte increments The default value for this byte is 80h 512 KBytes Valid values range from 20h to DOh 128 to 832 KBytes The Buffer Empty Ratio must equal the Buffer Full Ratio If these values are not equal the EXB 8500 returns Check Condition status with the sense key set to Illegal Request 5h Note The Buffer Full Ratio and the Buffer Empty Ratio in the Disconnect Reconnect Page for page format are equivalent to the Reconnect Threshold byte in the vendor unique parameters for non page format Bytes 04 and 05 Bus Inactivity Limit The EXB 8500 does not recognize any values other than 0 for the Bus Inactivity Limit It uses O as a default value meaning that there is no limit to the amount of time that the EXB 8500 can assert a BSY signal without a REQ ACK handshake Bytes 06 and 07 Disconnect Time Limit The only value supported by the EXB 8500 for the Disconnect Time Limit field is 0 This value
286. ta 510201 Appendix B 8500 Directory Support 5 Write the first data set DS 1 to the tape While the data set is being written issue additional READ POSITION commands as desired to obtain the locations of individual files blocks and so on contained in the data set Save the data returned for each READ POSITION command it will be written later to the data set s directory DIR 1 2 Issue iterative READ POSITION commands DIRECTORY PAD 12 PAD LFM DS1 1 Write the data 3 Store the First Block Location data 6 Once the first data set DS 1 has been written issue another READ POSITION command to obtain the starting location for the first data set s directory DIR 1 Save the information returned for the First Block Location field bytes 04 through 07 of the READ POSITION data This information will be used later to update the master directory at the beginning of the tape 1 Issue a READ POSITION command 2 Store the First Block Location data LBOT DIRECTORY PAD 12 MBYTE PAD LFM DS 1 December 1991 B 5 Appendix B 8500 Directory Support 7 Write the READ POSITION data obtained for the various files and blocks in the first data set DS 1 to the first data set s directory DIR 1 LBOT DIRECTORY PAD 12 MBYTE PAD LFM 51 DIR 1 write the data from the READ POSITI
287. ta transfer for that initiator 510201 6 SCSI Physical Path Communications Extended Message Processing message bytes in Send message byte 00 value 01h No Is Attention deasserted Send message byte 01 value 03h No Is Attention deasserted Send message byte 02 value 01h No Is Attention deasserted Send message byte 03 value xx Y Send Message Reject Is Attention deasserted Send message byte 04 value yy Is Attention asserted Continue processing Go to Message Out If the Attention signal is asserted and the message out is a Message Parity Error message then re send the last byte and continue processing Figure 6 6 Message Processing for Synchronous Data Transfer Request Message December 1991 6 23 6 SCSI Physical Path Communications Message Processing in Data Out Phase WRITE Command Figure 6 7 shows how each message is processed during the Data Out phase of a WRITE command Parity Error in User Data Associated with WRITE Command When parity checking is enabled and the EXB 8500 detects a parity error in the logical blocks of user data received from the initiator the EXB 8500 aborts the data transfer The data block containing the parity error is not written to tape After aborting the data transfer the EXB 8500 sends Check Condition status to the initiator followed by a Command Complete message
288. tape A value of 0 for this field indicates that a partially full buffer will not be flushed to tape The default value for this byte is 0 Valid values for this field are 0000h to 3FFFh A value greater than 3FFFh is not an error and will be truncated to 3FFFh Byte 08 Bit 7 DBR Data Buffer Recovery The DBR bit is not supported by the EXB 8500 The valid value for this bit is O 510201 12 MODE SELECT 15h Byte 08 Bit 6 BIS Block Identifier Supported The BIS bit indicates that block IDs are written on the tape relative to the single partition This bit is set to 1 in the MODE SENSE data and is ignored by the MODE SELECT command Byte 08 Bit 5 RSmk Report Setmarks The RSmk bit is not supported by the EXB 8500 The valid value for this bit is 0 Byte 08 Bit 4 AVC Automatic Velocity Control The AVC bit is not supported by the EXB 8500 The valid value for this bit is 0 Byte 08 Bits 3 and 2 SOCF Stop on Consecutive Filemarks The SOCF bit is not supported by the EXB 8500 The valid value for this bit is 0 Byte 08 Bit 1 RBO Recover Buffer Order The bit is not supported by the EXB 8500 The valid value for this bit is 0 Byte 08 Bit 0 REW Report Early Warning The REW bit is used to enable or disable reporting of the early warning condition LEOT during a read operation 0 Do not report early warning condition for read operations default 1 Report early warning condition for read
289. te 00 0 0 0 1 1 1 0 1 01 Logical Unit Number PE RSVD SelfTest DevOfL UntOfL 02 Reserved 03 MSB Parameter List Length 04 LSB 05 MD VU Reserved 0 0 December 1991 The SEND DIAGNOSTIC command causes the EXB 8500 to perform certain self diagnostic tests If a test is successful the EXB 8500 returns Good status otherwise it returns Check Condition status When this command is followed by a RECEIVE DIAGNOSTIC RESULTS 1Ch command or a REQUEST SENSE 03h command detailed results of these diagnostic tests are reported to the initiator Notes To ensure that the diagnostic data returned is valid the SEND DIAGNOSTIC command must be immediately followed by the RECEIVE DIAGNOSTIC RESULTS command To ensure that the results of the diagnostic test are not destroyed by a command sent by another initiator the EXB 8500 should be reserved for the initiator s exclusive use The initiator must support the disconnect option if you plan to use the SEND DIAGNOSTIC command because the EXB 8500 will disconnect from the initiator while the command is executing The SEND DIAGNOSTIC command returns Check Condition status with the sense key set to Illegal Request Sh and the ASC and ASCQ fields set to 53h and 02h under either of the following conditions a The Prevent bit in the PREVENT ALLOW MEDIA REMOVAL 1Eh command is set to 1 prevent media removal The NAL bit in MODE SELECT 15h is set to 0 autoloading
290. te that the execution of a command has terminated and that valid status has been sent to the initiator After successfully sending this message the EXB 8500 goes to the Bus Free phase 6 4 510201 6 SCSI Physical Path Communications Extended Message 01h The EXB 8500 supports only one Extended message the Synchronous Data Transfer Request message 01h Synchronous Data Transfer Request Bit 6 5 4 3 2 1 0 Byte 00 0 0 0 0 0 0 1 01 Extended Message Length 02 Extended Message Code 03 Transfer Period 04 REQ ACK Offset December 1991 The Synchronous Data Transfer Request message consists of five bytes The field definitions for these bytes are as follows Byte 00 Extended Message The valid value for the Extended Message field is 01 indicating that this is an extended message that contains multiple bytes Byte 01 Extended Message Length The valid value for the Extended Message Length field is 03h indicating that there are three additional message bytes to be transferred not including this byte Byte 02 Extended Message Code The Extended Message Code byte identifies the specific extended message being sent The valid value for this byte is O1h indicating that the Extended message is a Synchronous Data Transfer Request Byte 03 Transfer Period This byte identifies the minimum time allowed between leading edges of successive REQ pulses and ACK pulses for succes
291. te without Retries The WWR bit indicates whether the tape was written with retries as follows 0 The tape was written with retries 1 The tape was written with no retries Note The EXB 8500 writes a tape without retries when you issue MODE SELECT command at LBOT and set the Write Retry Count field located on the Read Write Error Recovery Page to OOh If the tape was written without retries it should be read without retries For this reason if the WWR bit is 1 issue a MODE SELECT command to set Read Retry Count field also located on the Read Write Error Recovery Page to 00h 510201 14 PREVENT ALLOW MEDIUM REMOVAL 1Eh Bit 7 6 5 4 3 2 1 0 Byte 00 0 0 0 1 1 1 1 0 01 Logical Unit Number Reserved 02 03 Reserved 04 Prevent 05 Vendor Unique Reserved 0 0 The PREVENT ALLOW MEDIUM REMOVAL command is used to allow or disallow the removal of the data cartridge from the EXB 8500 14 1 Field Definitions Byte 04 Bit 0 Prevent The Prevent bit is used to prevent the removal of the data cartridge from the EXB 8500 as follows 0 Allow the data cartridge to be removed 1 Prevent the data cartridge from being removed The prevent data cartridge removal condition terminates when any of the following conditions occur m APREVENT ALLOW MEDIUM REMOVAL command with the Prevent bit set to 0 is received from all initiators that set the pr
292. tes are reserved Bytes 96 through 105 Unit Serial Number The value contained in these bytes is the actual serial number of the EXB 8500 as listed on the serial number label The MSB is contained in byte 96 Serial numbers of less than 10 characters contain trailing blanks 20h 510201 9 INQUIRY 12h 9 3 Vital Product Data Page Bit 7 6 5 4 3 2 1 0 Byte 00 Peripheral Qualifier Peripheral Device Type 01 Page Code 02 Reserved 03 Page Length 04 First Page Code Supported 05 Second Page Code Supported December 1991 Field Definitions Byte 00 Bits 7 through 5 Peripheral Qualifier The value for this field 15 0 indicating that this is a single LUN device Byte 00 Bits 4 through 0 Peripheral Device Type The value returned for this field is OI h which identifies the EXB 8500 as a sequential access device Byte 01 Page Code The Page Code for the Vital Product Data page is 00h Byte 03 Page Length The value returned for this field 1s 02h which indicates the number of additional bytes available to be transferred excluding this byte Byte 04 First Page Code Supported The value returned for this field is which indicates support for the Vital Product Data page Byte 05 Second Page Code Supported The value returned for this field is 80h which indicates support for the Unit Serial Number page 9 7 9 INQUIRY 12h 9 4 Uni
293. tes the number Diagnostic Parameter bytes that follow this field Table 19 2 indicates the Page Length values for each Page Code supported by the RECEIVE DIAGNOSTIC RESULTS command Table 19 2 Page Lengths for RECEIVE DIAGNOSTIC RESULTS Command Page Code Value for Page Length field Total length of page 0001h 90h 1 byte 5 bytes 0001h 91h 1 byte 5 bytes 0000h to 9060h 94h 0 to 36 960 bytes 0 to 36 964 bytes Bytes 04 through nn Diagnostic Parameters The Diagnostic Parameters bytes start with byte 04 and are defined for each Diagnostic Page as follows Page Code 90h Test 100 or Test 110 Byte 04 Pass Fail Code This field indicates if the EXB 8500 passed or failed Test 100 or Test 110 power on test The following are the values and meanings for this field 00h Passed test Olh to FFh Failed test If the EXB 8500 failed the test the value returned for the Pass Fail Code corresponds to a Fault Symptom Code These codes are described in Appendix E Page Code 91h Test 101 and Test 111 Byte 04 Pass Fail Code This field indicates if the EXB 8500 passed or failed Test 101 or Test 111 power on write read and load tests The following are the values and meanings for this field 00h Passed test O1h to FFh Failed test If the EXB 8500 failed the test the value returned for the Pass Fail Code corresponds to a Fault Symptom Code These codes are described Appendix E 19 4 510201 19 RECEIVE DI
294. the EXB 8500 to go into unbuffered mode and to return Check Condition status after all of the data is written to tape The EOM bit is set to 1 and the LBOT bit is set to O in the extended sense data with the sense key set to No Sense The Valid bit is not set which indicates that all data was written to tape 28 8 510201 28 WRITE 0Ah PEOT Encountered If the physical end of tape PEOT is encountered the EXB 8500 returns Check Condition status and terminates the WRITE command The PEOT bit byte 21 bit 02 is set in the extended sense data and the sense key is set to Volume Overflow Dh If the Valid bit is set to 1 the Information bytes are set to either of the following m The requested transfer length if the Fixed bit is set to 0 m The difference between the requested transfer length and the actual number of blocks written if the Fixed bit is set to 1 Write Protected Data Cartridge If a write operation is attempted on a data cartridge that is write protected the EXB 8500 returns Check Condition status with the sense key set to Data Protect 7h Unrecoverable Error If an unrecoverable media or hardware error occurs during the write operation the EXB 8500 terminates the WRITE command and returns Check Condition status The sense key indicates a Medium Error 3h or Hardware Error 4h Indicators in the extended sense data can be used to isolate the error condition If the Valid bit is set to 1 the Informa
295. the EXB 8500 reconnects and returns status when the load or unload operation is complete If an error occurs during the writing of the data from the buffer to the tape the EXB 8500 reconnects to the initiator and returns Check Condition status The load or unload operation is not performed The initiator should issue a REQUEST SENSE 03h command to determine the cause of the error Byte 04 Bit 2 EOT This bit is ignored by the EXB 8500 Byte 04 Bit 1 Re Ten This bit is ignored by the EXB 8500 Byte 04 Bit 0 Load The Load bit indicates which operation load or unload is to be performed as follows 0 Perform an unload operation Perform a load operation 10 2 510201 December 1991 10 LOAD UNLOAD 1Bh Table 10 1 indicates what action occurs based on the setting of the Load bit and the status of the data cartridge Table 10 1 Action Occurring Based on Load Bit and Data Cartridge Status If the Load the data bit is set to cartridge is eee e 0 Out The door on the EXB 8500 is opened 1 Out Check Condition status is returned with the sense key set to Illegal Request 5h The data cartridge is unloaded If there is data in the write buffer the data is written to tape Then 0 In the tape is rewound to PBOT and unloaded from the tape path and the data cartridge is ejected from the EXB 8500 The data cartridge is loaded and positioned at LBOT If the data ca
296. these FSCs apply If the read back check criteria are not met for a data or short filemark block that is if the block is not perfect the block is rewritten If rewrite activity is excessive the EXB 8500 moves the tape backward reads the tape to verify that blocks are written and then moves the tape backward again It then performs a write splice operation and rewrites the blocks If the rewrite threshold is exceeded for any block the EXB 8500 returns Check Condition status with the sense key set to Medium Error 3h and the FSC set to 9Eh If the recovery splice operation cannot be completed the FSC is 9Dh E 6 510201 Appendix E Fault Symptom Codes EXB 8500 Error Recovery Procedures December 1991 Table E 2 describes the error recovery procedures ERPs recommended for each fault symptom code listed in Table E 1 Note If two or more ERP codes are listed for the Fault Symptom Code perform the action for the first code then perform the action for the second code and so on Table E 2 Recommended Error Recovery Procedures ERP Recommended Error Recovery Procedure Issue a REWIND command Issue a SPACE command to space backward over a block or a filemark Reissue the failed command or command sequence Correct the errors in the CDB bytes or parameter data Move the write protect switch on the data cartridge to write enable the tape Repeat the operation with a new data cartridge
297. thm 12 24 Field Definitions The Device Configuration Page is used only for page format that is when the PF bit in the CDB is set to 1 Byte 00 Bits 5 through 0 Page Code The Page Code identifies the type of MODE SELECT page being transferred This is the Device Configuration Page The valid value for Page Code is 10h Byte 01 Page Length The Page Length indicates the number of bytes in the Device Configuration Page that follow this byte The valid value for this byte is ODh Byte 02 Bit 6 CAP Change Active Partition The CAP bit is not supported by the EXB 8500 The valid value for this bit is 0 510201 12 MODE SELECT 15h Byte 02 Bit 5 CAF Change Active Format The CAF bit indicates that the active format is to be changed and to use the values in the Active Format field 0 Do not change active format Change active format Byte 02 Bits 4 through 0 Active Format The Active Format field contains data that modify the media format parameters The definition for the active format field is 4 3 2 1 0 Reserved Gap Threshold December 1991 Byte 02 Bits 4 and 3 Reserved These bits are reserved Byte 02 Bits 2 through 0 Gap Threshold The Gap Threshold byte specifies the maximum number of consecutive gap blocks that the EXB 8500 will write on the current track while determining whether an empty buffer exists during a write operation A
298. tiator as follows 0 Return the standard Inquiry Data Table 1 Return one of the Vital Product Data pages based on the value specified for the Page Code field byte 02 Byte 02 Page Code The Page Code field contains the page number of the Vital Product Data page to be returned to the initiator for this INQUIRY command The EXB 8500 supports the following values for the Page Code 00h Supported Vital Product Data Page 80h Unit Serial Number Page If the EVPD bit byte 1 bit 0 is set to 0 the Page Code must be 00h 9 INQUIRY 12h Byte 04 Allocation Length The Allocation Length specifies the number of bytes that the initiator has allocated for the return of Inquiry data A value of 0 indicates that no Inquiry data 15 to be transferred and 15 not an error The EXB 8500 terminates the Data In phase when the number of bytes specified in the Allocation Length field has been transferred or when all available Inquiry data has been transferred to the initiator whichever is less The amount of Inquiry data returned by the EXB 8500 depends on the type of data being returned as follows m Up to 6Ah 106 bytes for the Standard Inquiry Data Table or m 06h 6 bytes for the Supported Vital Product Data Page or m OEh 14 bytes for the Unit Serial Number Page Byte 05 Bits 7 and 6 Vendor Unique There are no vendor unique definitions for this command Returning Inquiry Data Table 9 1 summarizes the val
299. tion as follows 0 Do not release the third party reservation 1 Release the third party reservation Byte 01 Bits 3 through 1 Third Party Device ID The Third Party Dev ID field indicates the SCSI ID of the device for which the EXB 8500 is reserved Byte 05 Bits 7 and 6 Vendor Unique There are no vendor unique definitions for this command 20 1 20 RELEASE UNIT 17h Notes 20 2 510201 21 REQUEST SENSE 03h Bit 7 6 5 4 3 2 1 0 Byte 00 0 0 0 0 0 0 1 1 01 Logical Unit Number Reserved 02 Reserved 03 04 Allocation Length 05 CLRCNT VU Reserved 0 0 The REQUEST SENSE command requests that the EXB 8500 transfer sense data to the initiator The EXB 8500 returns a total of 29 1Dh bytes of sense data to the initiator The sense data is valid for the Check Condition status just presented to the initiator This sense data is preserved in the EXB 8500 for the initiator receiving the Check Condition status Sense data is cleared when any subsequent command that is not a REQUEST SENSE or an INQUIRY 12h command is received from the initiator receiving the Check Condition status 21 1 Field Definitions December 1991 Byte 04 Allocation Length The Allocation Length field specifies the number of bytes that the initiator has allocated for returned sense data The EXB 8500 provides a total of 29 1Dh bytes of sense data Byte
300. tion bits are set to either of the following m The requested transfer length if the Fixed bit is set to 0 m The difference between the requested transfer length and the actual number of blocks written to the tape if the Fixed bit is set to 1 If another WRITE command is issued after an unrecoverable error occurs the EXB 8500 returns Check Condition status with the sense key set to Medium or Hardware error and the command is not executed December 1991 28 9 28 WRITE 0Ah 28 10 Illegal Requests The following conditions cause the EXB 8500 to return Check Condition status with the sense key set to Illegal Request 5h The Fixed bit is set to 0 and the requested block length is greater than 240 KBytes or greater than 160 KBytes with the ND bit set to 1 The Fixed bit is set to and the block length in the MODE SELECT command is not 0 The Fixed bit is set to 1 and the block length in the MODE SELECT command is 0 The tape position is invalid A READ 08h LOCATE 2Bh in a forward direction or VERIFY 13h command is issued after the WRITE command is issued 510201 29 WRITE BUFFER 3Bh Bit 7 6 5 4 3 2 1 0 Byte 00 0 0 1 1 1 0 1 1 01 Logical Unit Number Reserved Mode 02 Buffer ID 03 MSB 04 Buffer Offset 05 LSB 06 MSB 07 Parameter List Length 08 LSB 09 WBF VU Reserved 0 0 December 1991 The WRITE BUFFER
301. tioning the tape to the logical beginning of tape LBOT Unloading a data cartridge involves the following 1 If necessary writing any buffered data and filemarks to tape 2 Rewinding the tape to the physical beginning of tape PBOT 3 Unloading the tape from the tape path 4 Ejecting the data cartridge Note If there is data in the buffer because an earlier WRITE OAh command was terminated with Check Condition status that data is discarded before the LOAD UNLOAD command is executed 10 1 Field Definitions December 1991 Byte 01 Bit 1 Immed The Immed bit is used to determine when command status is returned to the initiator as follows 0 Status is reported to the initiator when the load unload operation 15 complete Status is reported to the initiator when the command is initiated by the EXB 8500 10 1 10 LOAD UNLOAD 1Bh If the buffer contains data from a previous WRITE command the EXB 8500 disconnects from the SCSI bus if disconnect was enabled by the Identify message and writes the data in the buffer to the tape m If the Immed bit is set to 1 the EXB 8500 reconnects to the initiator when the write operation has been completed successfully It then returns Good status and performs the load or unload operation Note Completing the write operation includes emptying the buffer and writing the EOD mark EXB 8500 format tapes only This can take up to 12 seconds m If the Immed bit is set to 0
302. tly active MODE SELECT command bytes 5 through 7 of the Block Descriptor Note The EXB 8500 returns Check Condition status with the sense key set to Illegal Request 5h in the following cases m The Fixed field in the VERIFY command is 0 variable length logical block and the Block Length field in the current MODE SELECT data is greater than 0 fixed length logical blocks m The Fixed field in the VERIFY command is 1 fixed length logical blocks and the Block Length field in the current MODE SELECT data is 0 variable length logical block The ASC and ASCQ bits are set to 81h and OOh fixed variable mismatch Bytes 02 through 04 Verification Length The Verification Length field defines the amount of data to be verified as follows m When the Fixed bit is set to 0 the Verification Length field contains the length of the logical block in bytes The logical block can be any size from 0 to 240 Kbytes Note Ifthe No Disconnect During Data Transfer ND bit is set the logical block can be any size from 0 to 160 KBytes See Chapter 12 for more information m When the Fixed bit is set to 1 the Verification Length field contains the number of logical blocks to be verified The block length is the length specified with the MODE SELECT command Note When the value for the Verification Length field is 0 no data is verified and the current position of the EXB 8500 is not changed Byte 05 Bits 7 and 6 Vendor Unique There are
303. to No Sense The Information bytes indicate the number of blocks not verified including the block with the incorrect length When the VERIFY command terminates in either fixed or variable mode the tape 15 positioned after the block with the incorrect length December 1991 27 5 27 VERIFY 13h Illegal Requests The following conditions cause the EXB 8500 to return Check Condition status with the sense key set to Illegal Request 5h m The Fixed bit is set to 0 and the requested block length is greater than 240 KBytes or 160 KBytes if the ND bit is set m The Fixed bit is set to 0 and the block length in the MODE SELECT command is not 0 m The Fixed bit is set to 1 and the block length in the MODE SELECT command is 0 m A VERIFY command is issued immediately after a WRITE or WRITE FILEMARKS command has been executed 27 6 510201 28 WRITE 0Ah Bit 7 6 5 4 3 2 1 0 Byte 00 0 0 0 0 1 0 1 0 01 Logical Unit Number Reserved Fixed 02 MSB 03 Transfer Length 04 LSB 05 Vendor Unique Reserved 0 0 The WRITE command transfers one or more bytes or blocks of data from the initiator to the EXB 8500 As described in Section 3 1 the EXB 8500 can write data in EXB 8500 format or in EXB 8200 format The data format is set with the MODE SELECT 15h command Only one data format can be written on a data cartridge Note If the disconnect option is enabled th
304. to meet the demands of super mini and mainframe computer systems The EXB 8500 shown in Figure 1 1 is packaged in the industry standard 5 25 inch form factor and provides up to 5 000 megabytes S gigabytes of data storage capacity on a single standard 8mm data cartridge By using dual read and write head pairs with helical scan recording technology the EXB 8500 can achieve a transfer rate of up to 500 KBytes per second with peak transfer rates of up to 4 MBytes per second The EXB 8500 uses sophisticated error correction code ECC and error recovery procedures along with full read after write verification to ensure data integrity Data interchange is maintained through read and write compatibility with other EXABYTE 8mm Cartridge Tape Subsystems including the EXB 8200 82005 EXB 8205 and EXB 8500c The EXB 8500 includes a Small Computer System Interface SCST controller and is available in single ended and differential SCSI configurations For detailed information about EXB 8500 specifications refer to the 8500 6mm Cartridge Tape Subsystem Product Specification December 1991 1 3 1 General Information Figure 1 1 EXABYTE EXB 8500 8mm Cartridge Tape Subsystem 1 2 About This Manual This manual includes the following information Part 1 includes this chapter and Chapters 2 through 5 Read Part 1 to learn about installing operating cleaning and shipping the EXB 8500 and downloading microco
305. to page format for the MODE SELECT parameters that is SCSI 2 format In page format the MODE SENSE parameters are returned in the following order 1 Parameter List Header 4 bytes 2 Block Descriptor 8 bytes optional 3 Oneorsix pages of related parameters page format 13 1 Field Definitions 13 2 Byte 01 Bit 4 RSVD This bit is reserved Byte 01 Bit 3 DBD Disable Block Descriptor The Disable Block Descriptor bit indicates whether the initiator wants the 8 byte Block Descriptor returned as part of the MODE SENSE parameter data This bit is defined as follows 0 Send the Block Descriptor 1 Do not send the Block Descriptor Note The DBD bit must be 0 if the Page Code is 0 non page format Otherwise the EXB 8500 will return Check Condition status with the sense key set to Illegal Request Sh When the Page Code is 0 use the Allocation Length byte to specify whether the Block Descriptor is returned see Table 13 2 Byte 02 Bits 7 and 6 PC Page Control The Page Control field indicates the type of MODE SENSE parameter data to be returned The EXB 8500 supports only current values 00h indicating that the values returned are one of the following m The parameters set by the last successful MODE SELECT command m The power on default values if a MODE SELECT command has not been executed since the last power on reset SCSI bus reset or Bus Device Reset message Note that this field is used o
306. tor Figure 2 3 shows the location of the pins on the remote connector y Remote Connector J tC REOS VA NA ND a 4 e hak RM P3 SR T v mS X p di Uis Bw rs N 3 ES S c SS fa N fe 1 5 S J NI F M b Ao 25h V J L CN D IS Eb CQ N VE KU p y A N 227 cC Pin Locotions These lab jo not appeor on the SIF DIF card Figure 2 3 Location of the Pins on the Remote Connector 5 Change the settings on the remote switch to the correct address for your configuration Table 2 1 shows the pin assignments for the remote connector Note that the switch settings for the remote connector should emulate the jumper positions shown in Figure 2 4 Table 2 1 Pin Assignments on the Remote Connector Pin Assignment 1 SCSI ID Bit 2 MSb 2 Ground 3 SCSI ID Bit 1 4 Ground 5 SCSI ID Bit 0 LSb 6 Ground 2 6 510201 2 Installing the EXB 8500 Setting the SCSI ID with Jumpers To set the SCSI ID using jumpers provided with the EXB 8500 follow these steps 1 Locate the DIP switches labeled U2 on the back of the EXB 8500 as shown in Figure 2 1 2 Setall three DIP switches to off address 3 Locate the remote connector labeled P3 on the back of the EXB 8500 as shown in Figure 2 1 4 Connect jumpers to the pins on the remote connector to obtain the correct address for you
307. transferred from the EXB 8500 to the initiator When the value for this byte is 0 no data is transferred from the initiator A value of 0 for this byte is not an error m For any data transfer greater than O bytes the entire 4 byte Parameter List Header must be transferred That is the entire 4 byte Parameter List Header must be transferred before the Block Descriptor or any parameter page can be transferred m The Block Descriptor and any parameter pages must be transferred in their entirety partial transfers of these data segments are not allowed Note Any value for the Allocation Length that causes the Parameter List Header Block Descriptor or one of the parameter pages to be truncated will terminate the command with Check Condition status The sense key will be set to Illegal Request and the Additional Sense Code will be set to Parameter List Length Error The partial page will be transferred Byte 05 Bits 7 and 6 Vendor Unique There are no vendor unique definitions for these bits December 1991 13 7 13 MODE SENSE 13 2 Parameter List Header Non Page and Page Formats Bit 7 5 4 3 2 1 0 Byte 00 Mode Data Length 01 Medium Type 02 WP Buffered Mode Speed 03 Block Descriptor Length 13 8 Field Definitions The Parameter List Header is the same for both non page and page formats Byte 00 Mode Data Length The Mode Data Length byte represent
308. ues a RECEIVE DIAGNOSTIC RESULTS command with the TD bit set to 0 the EXB 8500 returns a diagnostic page This page reports the results of the previous SEND DIAGNOSTIC command Three types of diagnostic pages can be returned the type of page depends on which diagnostic test was performed by the SEND DIAGNOSTIC command As described in Section 19 3 no diagnostic page is returned if the TD Trace Dump bit is set to 1 rather a trace dump is returned Note ensure that data in the diagnostic page is valid be sure that the RECEIVE DIAGNOSTIC RESULTS command immediately follows the SEND DIAGNOSTIC command and that the EXB 8500 is reserved for the initiator s exclusive use Block Diagram for the Diagnostic Page Bit T 6 5 4 3 2 1 0 Byte 00 Page Code 01 Reserved 02 MSB Page Length 03 LSB 04 Diagnostic Parameters nn Field Definitions for the Diagnostic Page Byte 00 Page Code The Page Code field identifies which of the three types of diagnostic pages is being returned The EXB 8500 supports the Page Codes listed in Table 19 1 Table 19 1 Page Codes for RECEIVE DIAGNOSTIC RESULTS Command Returned for Page Code 90h Test 100 or Test 110 Power on test 91h 94h December 1991 Test 101 or Test 111 Power on write read and load tests Memory Dump 19 3 19 RECEIVE DIAGNOSTIC RESULTS 1Ch Bytes 02 and 03 Page Length The Page Length field indica
309. ues you should specify to return the different types of Inquiry data Table 9 1 Values to Specify for the Return of Different Types of Inquiry Data To return this Inaulr Set these fields to And specify this Number of data quiry value for the Bytes Returned E EVPD Page Code Allocation Length hex Standard Inquiry Data 0 00h any value 0 to 106 bytes Table from 0 to FFh Oh to 6Ah Supported Vital Product 6 bytes Data Page pon uon 06h 14 bytes Unit Serial Number Page 1 80h OEh OEh 9 2 510201 9 INQUIRY 12h 9 2 Standard Inquiry Data Bit 7 6 5 4 3 2 1 0 Byte 00 Peripheral Qualifier Peripheral Device Type 01 RMB Device Type Modifier 02 ISO Version ECMA Version ANSI Version 03 AENC TrmlOP Reserved Response Data Format 04 Additional Length Reserved 06 07 RelAdr 532 WBus16 Sync Linked RSVD CmdQue SftRe 08 Vendor Identification 15 16 Product Identification 31 32 Product Revision Level 35 36 l Vendor Specific 55 56 Reserved 95 96 Unit Serial Number 105 December 1991 9 3 9 INQUIRY 12h 9 4 Field Definitions The Standard Inquiry Data is returned to the initiator when EVPD Byte 01 Bit 0 of the CDB is set to 0 The 106 bytes of Standard Inquiry Data are defined as follows Byte 00 Bit
310. uffer Full Ratio Note The Write Buffer Full Ratio and the Read Buffer Empty Ratio in the Device Configuration Page have the same function as the Motion Threshold in the Vendor Unique Parameters Page 1 Bytes 06 and 07 Write Delay Time If a WRITE command completes without transferring enough data to exceed the Write Buffer Full Ratio the value specified by the Write Delay Time field 15 used to determine the maximum amount of time in units of 100 msec that the data will remain in the buffer When the time specified by Write Delay Time expires the data in the buffer is automatically written to tape A value of 0 for this field indicates that a partially full buffer will not be flushed to tape The default value for this byte is 0 Values returned for this field range from 0000h to 3FFFh Byte 08 Bit 7 DBR Data Buffer Recovery The DBR bit is not supported by the EXB 8500 The value returned for this bit is 0 Byte 08 Bit 6 BIS Block Identifier Supported The BIS bit indicates that block IDs are written on the tape relative to the single partition This bit is set to 1 in the MODE SENSE data and is ignored by the MODE SELECT command Byte 08 Bit 5 RSmk Report Setmarks The RSmk bit is not supported by the EXB 8500 The value returned for this bit is 0 Byte 08 Bit 4 AVC Automatic Velocity Control The AVC bit is not supported by the EXB 8500 The value returned for this bit is 0 Byte 08 Bits 3 and 2 SOCF St
311. utton setting the EXB 8500 will unload the tape even if errors are present during the unload procedure unless the error is a serious hardware error 3 21 3 Operating the 8500 Notes 3 22 510201 4 Cleaning and Packing the EXB 8500 This chapter describes how to clean the EXB 8500 s tape heads and tape path and provides procedures for packing the EXB 8500 for shipment Note Except for cleaning the EXB 8500 has no user serviceable adjustments or maintenance procedures All service or repairs to the EXB 8500 must be performed by EXABYTE Corporation or by authorized service personnel 4 1 Cleaning the EXB 8500 The EXB 8500 s heads and tape path should be cleaned on a regular basis The only cleaning material authorized for use with the EXB 8500 is an EXABYTE or EXABYTE approved 8mm Cleaning Cartridge Important Using cloth swabs cotton swabs cleaning agents or cleaning cartridges not approved by EXABYTE Corporation will void the warranty on the EXB 8500 Use the following guidelines to determine how often to clean the EXB 8500 m Whenusing the EXB 8500 to read and write data in EXB 8500 format clean the tape heads and tape path once a month or after 60 GBytes of data transfer whichever occurs first For planning purposes approximately 2 GBytes of data are transferred per hour of operation in EXB 8500 mode m Whenusing the EXB 8500 to read and write data in EXB 8200 format clean the tape heads and tape
312. uus doe rax eoe ue Sk 4 or a 27 4 Unr coyerable POO 4 udo eS pe 4S SHES A S eps 27 4 Verification Length Incorrect 4 4 doe om x RD ow 3 da oe 27 5 Ill sal Reguesis E sie OSG Dee Ged ges ck X sa X XD oa 27 6 2B WRITE GAN wee eS oe ec eee 28 1 28 1 Field Definitions 1233 4 999 SERS SEES SESS RE 28 1 28 2 Tape POSIUONHIHE eu oue xe wn o mk He ee ed ee ed ee dos 28 3 28 3 Data Buffering x be ee eR ERED 3 Sox 3 amp 9 9 3 309 EE ESS 28 4 28 4 Exceptions and Error Conditions iux o9 o 6 ox XU os 28 5 LEOT Bacoubtered ssa i vx 6 ea ek eee ole dx os xs 28 5 PEOT Encountered s s se acou da podon d mo 3 99 2545 5 SS m bos 28 0 Wn ie Protected Data Cartridge 45406 44 28 0 Unrecoverable Error ous ow Ve eae IRE E RAE Y v x e 28 0 Ilegal C CC 28 10 December 1991 xiii 29 WRITE BUFFER SBR us nO a In Rm n 29 1 Cautions for Using the WRITE BUFFER Command 20 2 Time Required to Load Code with WRITE BUFFER 29 3 29 1 Field Definitions eewe Gee 3o Sob Eo 29 3 20 2 Exceptions and Error Conditions 42212639 ndn de dox 25 29 5 Aborting a WRITE BUFFER Command or Command Sequence 29 5 Microcode Not Valid 4 uu sce ovo om bee bee 20 5 Fatal Load Error 1 us s
313. where various data sets are located on the tape and can include the following types of information m The names of the data sets on the tape You can use this information to determine quickly what data is on the tape For example if you want to know which of several tapes contain a particular data set you can simply read the directory at the beginning of each tape m The locations of the data sets on the tape You can use this information to take advantage of the EXB 8500 s high speed search capability Once you know a data set s location you can issue a LOCATE 2Bh or SPACE 11h command to move to that data set at 75 times the normal tape speed that is at a rate of up to 37 5 MBytes per second When the EXB 8500 includes the EEPROM image for directory support the EXB 8500 allows the tape to have two end of data EOD marks one at the end of the directory and the other at the actual end of data on the tape As long as the first EOD mark is located before the first filemark the EXB 8500 can space over it As described in the sample application in Appendix B you perform the following types of steps to create a directory at the beginning of the tape 1 Reserve an area of the tape after LBOT for the directory this is called the directory pad 2 Write a long filemark to separate the directory pad from the data area of the tape 3 Issue a READ POSITION 34h command to determine the starting location for the first data set Save
314. write protected December 1991 13 9 13 MODE SENSE 1Ah 13 10 Byte 02 Bits 6 through 4 Buffered Mode The EXB 8500 supports two data transfer modes as follows 000 Unbuffered mode 001 Buffered mode In buffered mode data from a WRITE command and filemarks from a WRITE FILEMARKS command EXB 8500 format only are held in the EXB 8500 s buffer until one of the following events causes the data and filemarks to be written to the tape m The motion threshold is reached m The EXB 8500 receives one of the following commands REWIND 01h WRITE 5 10h non immediate SPACE 11h in either direction ERASE 19h LOAD UNLOAD 1Bh LOCATE 2Bh in the reverse direction LD oDODOCLDZLU m The operator presses the unload button m The time specified for the Write Delay Time field elapses note however if the Write Delay Time field is 0 a partially full buffer is not flushed to tape Note The Write Delay Time field can be set using page format only see Section 12 8 for more information In buffered mode status is returned when the last block of data has been transferred to the EXB 8500 s buffer In unbuffered mode status is returned only after the data has actually been written to the tape The power on default value for the Buffered Mode field is 001 Byte 02 Bits 3 through 0 Speed The EXB 8500 does not support any operations at different speeds AII operations have a defined spee
315. written on the tape in step 5 December 1991 2 13 2 Installing the EXB 8500 8 Repeat steps 5 through 7 at least two times or for two hours whichever is greater Note Ifthe EXB 8500 has been stored for long period errors may occur during the break in period If an error occurs reset the EXB 8500 and repeat steps 4 though 8 as appropriate When you have completed step 8 the EXB 8500 is ready for normal operation 2 14 510201 3 Operating the EXB 8500 This chapter discusses EXB 8500 operation It includes information about the following December 1991 The read and write compatibility of the EXB 8500 with other EXABYTE 8mm Cartridge Tape Subsystems The differences between EXB 8500 format and EXB 8200 format The EXB 8500 s ability to operate in streaming and start stop modes The EXB 8500 s optional directory support feature available from EXABYTE as a special EEPROM image The configuration options that can be set with the CTS Monitor program to control EXB 8500 operation EXB 8500 operator controls and indicators including a description of the unload button options and a table showing the EXB 8500 states depicted by the LEDs How to set the write protect switch on the data cartridge How to load and unload data cartridges Note Refer to the 8500 8mm Cartridge Tape Subsystem Product Specification for operating specifications for the EXB 8500 3 Operating the 8500 3 1 Read Write Compatibi
316. xceeded 97h 3h 6 Write EOD failure after internal retry limit exceeded 98h 4h 8 12 Hardware failure Invalid BRT December 1991 E 3 Appendix E Fault Symptom Codes FSC SK ERP Description 99h 4h 8 12 Hardware failure Buffer empty 9Ah 4h 8 12 Hardware failure Deformatter Intrp timeout on search 9Ch 4h 8 12 Hardware failure Formatter Intrp timeout on write 9Dh 3h 6 Permanent write error Write recovery failure 9Eh 3h 6 Permanent write error Rewrite threshold exceeded 9Fh 3h 6 Servo zone read back check failure Aih 4h 8 12 Hardware failure Head sync error during write A2h 4h 8 12 Underrun error during write A3h 4h 8 12 IPORT write buffer parity error A4h 4h 8 12 DPORT write buffer parity error A5h 4h 8 12 PPORT write buffer parity error A6h 4h 8 12 IPORT read buffer parity error A7h 4h 8 12 DPORT read buffer parity error A8h 4h 8 12 PPORT read buffer parity error ABh 4h 12 Servo timed out ACh 4h 8 12 Servo software error ADh 4h 8 12 Servo hardware failure AEh 3h 6 9 Unable to achieve or maintain tracking AFh Dh 11 EOT encountered during a tape motion command B3h 3h 6 pe 2n failure read back check criteria not met after retry limit B4h 3h 6 9 LBOT failure unable to write tape mark tracks in EXB 8200 mode B5h 3h 9 Physical Read Manag
317. xt command other than INQUIRY or REQUEST SENSE is received by the EXB 8500 7h Data Protect Indicates that a command that writes to tape was attempted on a write protected data cartridge The write operation is not performed 8h Blank Check Indicates that EOD blank tape was encountered during a read space or locate operation 9h EXABYTE This is a vendor unique sense key used by EXABYTE to indicate that a positioning error has occurred The actual position of the EXB 8500 is undetermined and is not the expected position Ah Copy Aborted This sense condition is not supported by the EXB 8500 21 4 510201 21 REQUEST SENSE 03h Sense Key Meaning Explanation Indicates that the EXB 8500 aborted the command This condition occurs when an Initiator Detected Error 05h message is received during command execution or when a Message Reject 07h or SCSI bus parity error is detected by Bn Rbonad Command the EXB 8500 during Command or Data Out phase The initiator may be able to recover by trying the command again Ch Equal This sense condition is not supported by the EXB 8500 Dh Volume Cy ertiow Indicates that the last WRITE or WRITE FILEMARKS command reached PEOT and that data may remain in the buffer Eh Miscompare This sense condition is not supported by the EXB 8500 Fh Reserved Reserved for future implementation in the ANSI SCSI standard
318. xtended Message Processing message bytes out Receive message byte 00 Is it O1h and is the Attention signal asserted Receive message byte 01 Is it O3h and is the Attention signal asserted Receive message byte 02 Is it O1h and is the Attention signal asserted Receive message byte 03 Is the Attention signal asserted Receive message byte 04 Is the Attention signal asserted Go to Message IN Send Message Reject Go to Message IN EE Send Synchronous Data Transfer Request Figure 6 5 Message Processing of Extended Message Out Bytes December 1991 6 21 6 SCSI Physical Path Communications 6 22 Processing of Extended Message In Figure 6 6 shows how the Extended Message In messages are processed The EXB 8500 executes this message sequence in response to an initiator s Synchronous Data Transfer Request Parity Error in Extended Message In If the initiator detects a parity error in the Synchronous Data Transfer Request byte being sent by the EXB 8500 it responds by sending a Message Parity Error message to the EXB 8500 The EXB 8500 responds by re sending the Synchronous Data Transfer Request byte If the EXB 8500 receives 16 consecutive Message Parity Error messages or one Message Reject message it cancels the Synchronous Data Transfer Request and resumes asynchronous da
319. y The EXB 8500 operates from standard 5 VDC and 12 VDC supply voltages it does not use external AC power Refer to the EXB 8500 8mm Cartridge Tape Subsystem Product Specification for detailed information about power specifications refer to Appendix A for information about the power cable CAUTION The EXB 8500 does not provide any overvoltage or overcurrent protection For this reason be sure that the power is off before connecting the EXB 8500 to a power supply To connect power to the EXB 8500 follow these steps 1 If additional chassis grounding is desired connect a 4 inch female spade connector to the ground tab or an M3 0 5 x 6 mm self tapping screw to the grounding hole on the rear of the EXB 8500 shown in Figure 2 1 2 Locate the power connector labeled P1 on the back of the EXB 8500 as shown in Figure 2 1 3 Connect the power cable to the power connector CAUTION The power cable plug and the power connector are keyed so they can fit together in only one way Before attempting to connect the plug to the EXB 8500 be sure that the beveled edges of the plug are oriented in the same way as the beveled edges on the power connector Do not force the plug into the connector or you may damage the EXB 8500 2 12 510201 2 Installing the EXB 8500 2 7 Performing the Initial Power On After you have connected the EXB 8500 to the power supply you can perform the initial power on As described in this s
320. y the number of bytes to be returned in the Allocation Length field December 1991 24 3 24 SEND DIAGNOSTIC 1 Note Ifthe starting address specified in the Parameter List Length field combined with the number of bytes specified in the Allocation Length field results in a reference to an address greater than 97FFh the EXB 8500 resets wraps the address to 0000h Table 24 2 indicates the values to specify for the Parameter List Length field to reference the three types of EXB 8500 memory Table 24 2 Values for SEND DIAGNOSTIC Command Parameter List Memory Address Type of Memory 0 to FFh Processor on chip memory 100h to 7FFFh External RAM 8000h to 97FFh LSI hardware registers Note Ifthe initiator requests more bytes than are available that is more than 9064h bytes the EXB 8500 will send all available bytes and then terminate This is not an error Test 100 Power on Tests without Tape During this test the EXB 8500 performs its power on RAM and servo diagnostic tests The EXB 8500 returns Good status if it finds no errors Incorrect test setup causes the EXB 8500 to return Check Condition status with the sense key set to Illegal Request The EXB 8500 disconnects during this test Note Test 100 cancels all synchronous negotiations and erases the trace tables In addition the unload button is disabled during this test Setup for Test 100 Before starting this test power the EXB
321. ysical tracks The single servo head SVO reads the servo data that was written on the tape by the second write head W2 The servo data is used to ensure accurate positioning of the read heads over the tracks Of the two tracks in the pair track 1 has a 20 degree azimuth This track is written by head W1 and read by head R1 Track 2 has a 10 degree azimuth This track is written by head W2 and read by heads R2 and SVO Track Structure EXB 8200 Format When writing and reading data in EXB 8200 format the EXB 8500 uses the W2 R2 and SVO heads to write and read a single track with a 10 degree azimuth Physical Blocks In both EXB 8500 format and EXB 8200 format each physical track contains eight physical blocks A physical block can contain user data and other information In both formats a physical block containing user data includes the following information 14 bytes of header information 1 024 bytes of user data 2 bytes of cyclic redundancy check CRC data 400 bytes of error correction code ECC data Note This information is arranged somewhat differently in EXB 8500 format than in EXB 8200 format Since each physical track contains eight physical blocks each track can contain a maximum of 8 192 bytes of user data The header ECC data and CRC data do not affect the data capacity of the tape Logical Blocks A logical block is a block of data transferred from the initiator to the EXB 8500 In both EXB 8500 form

EXB-8500 User`s Manual

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