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Resolution T GPS Embedded Board User Guide

1. Resolution T GPS Embedded Board User Guide Trimble Standard Interface Protocol A Command Packet 0x8E 15 Request Current Datum Values This packet contains only the subpacket ID 0x15 The response to this packet is 8F 15 Command Packet 0x8E 26 Write Receiver Configuration to Flash ROM This command packet causes the current configuration settings to be written to the flash ROM This packet contains only a single byte the sub packet ID Note that the unit will reset itself following the execution of this command N WARNING The Resolution T GPS receiver is ready to accept TSIP commands approximately 2 1 seconds after power up If a command is sent to the receiver within this 2 1 second window the receiver will ignore the command The Resolution T GPS receiver will not respond to commands sent within the 2 1 second window and will discard any associated command data Command Packet 0x8E 41 Request Manufacturing Parameters This packet is used to request the manufacturing parameters stored in nonvolatile memory Send this packet with no data bytes dont forget the subcode to request packet Ox8F 41 Command Packet Ox8E 42 Stored Production Parameters This packet is used to request the production parameters stored in nonvolatile memory Send this packet with no data bytes dont forget the subcode to request packet Ox8F 42 Command Packet Ox8E 4A Set PPS Characteristics This packet allows the user to query by sending t
2. Resolution T GPS Embedded Board User Guide Hardware Integration 3 Serial interface The Resolution T GPS receiver provides direct CMOS compatible serial I O The RX and TX signals on the J4 I O connector are driven directly by the UART on the Resolution T GPS receiver Interfacing these signals directly to a UART in your application circuitry provides direct serial communication without the complication of RS 232 or RS 422 line drivers Pulse per second PPS The Resolution T GPS timing receiver provides a one millisecond wide CMOS compatible Pulse Per Second PPS The PPS is a positive pulse available on pin 6 of the power and I O connector The rising edge of the PPS pulse is synchronized with respect to UTC The timing accuracy is within 15 nanoseconds 1 6 to UTC when valid position fixes are being reported in the Overdetermined Mode The rising edge of the pulse is typically less than 20 nanoseconds The distributed impedance of the attached signal line and input circuit can affect the pulse shape and rise time The PPS can drive aload up to 5mA without damaging the receiver Mounting There are four mounting holes at the corners of the PCB that accept 3 16 hex or round standoffs with a g height and 2 2 56 or M2 mounting screws Space constrained environments may require a different standoff GPS antenna Trimble offers the following two antenna options for use with the Resolution T GPS receiver Resolution T GPS Em
3. e Local Clock Bias Rate This field contains the bias rate ofthe local clock Note that this data cannot be used to increase the accuracy of the PPS output e Temperature This field shows the temperature in Celsius as reported by the Resolution T s on board temperature sensor e Latitude This field carries the latitude of the position being shown The units are in radians and vary from pi 2 to pi 2 Negative values represent southern latitudes Positive values represent northern latitudes e Longitude This field carries the longitude ofthe position being shown The units are in radians and vary from pi to pi Negative values represent western longitudes Positive values represent eastern longitudes e Altitude This field carries the altitude of the position being shown The units are in meters WGS 84 e PPS Quantization Error This field carries the PPS quantization error in units of seconds Byte Item Type Value Description 0 Subcode UINT8 OxAC 1 Receiver Mode UINT8 Automatic 2D 3D Single Satellite Time Horizontal 2D Full Position 3D DGPR Reference Clock Hold 2D Overdetermined Clock N Ou BW O 80 Resolution T GPS Embedded Board User Guide Trimble Standard Interface Protocol A Byte Item Type Value Description 2 Reserved UINT8 0 Reserved 1 2 3 4 5 6 3 Self Survey Progress UINT 8 0 100 4 7 Reserved UINT 32 0 Reserved 8 9 Reserved UINT16 0 Reserved 10 11 Minor Alarms UINT16 bit
4. Test Mode 0 Data Fields Field Description Test Mode Set this field to 0 to exit test mode and return the Resolution T to normal operations A reset or power cycle will also cause the Resolution T to exit test mode Test Mode 0 Data Format Byte Item Type Description 0 Subcode UINT8 OxA4 1 Test Mode UINT8 0 Exit test mode Test Mode 1 Data Fields Field Description Test Mode Setting this field to 1 tells the Resolution T to enter the user time test mode The Resolution T will set the time to the week number and TOW sent with this packet The Resolution T will then increment this time once per second The time in packets 8F AB and 8F A7 will show the user test time but all other packets that have time fields will be unaffected Week Number This field contains the week number for the user time test mode Time of Week This field contains the TOW for the user time test mode Test Mode 1 Data Format Byte Item Type Description 0 Subcode UINT8 OxA4 1 Test Mode UINT8 1 Set absolute time ignore GPS time 2 3 Week Number UINT16 Week number 0 1023 4 7 Time of Week UINT32 Seconds 0 604799 Resolution T GPS Embedded Board User Guide 71 A Trimble Standard Interface Protocol Test Mode 3 Data Fields Note For a more detailed description of UTC parameters see the GPS SPS Signal Specification Field Description Test Mode Setting this field to 3 tells the Resolution T that the following fi
5. For example in packet Ox8E 15 15 is the subcode that indicates the superpacket type Therefore the ID code for these packets is 2 bytes long followed by the data Command Packet Ox8E 01 Configure Raw GPS Data Output TSIP super packet Ox8E 01 is used to configure raw GPS data output In the auto send mode a subframe is automatically sent out for each tracked satellite as soon as it is decoded every 6 seconds of continuous tracking Therefore in the auto send mode at most 12 report packets Ox8F 01 will be sent out every 6 seconds for a 12 channel receiver In the request mode a specific subframe can be queried for a particular satellite The returned data reflects the last valid subframe collected for that satellite it may not be current If the satellite is not tracked or the specified subframe has not been collected yet a short report packet is returned with the Status field of the packet indicating the error code The data fields of this command packet following the packet ID Ox8E are as follows Byte Item Type Value Definition 0 Sub code U8 0x01 Packet Ox8E 8F sub code 1 Operation U8 0 Turn off auto send mode 1 Turn on auto send mode 2 Request data for specific SV 2 SV ID U8 1 32 Satellite ID for which to request data This field is ignored when Operation is 0 or 1 3 Subframe ID U8 0 5 Subframe ID for which to send data 0 to request all subframes for that SV This field is ignored when Operation is O or 1
6. If more than one of the formats is masked on for broadcast then the format with the greatest precision of content masked on will be sent and the rest will not For each bit in the mask that is used the coding is as follows 72 Resolution T GPS Embedded Board User Guide Trimble Standard Interface Protocol A 0 Turn off broadcast of this packet 1 Turn on broadcast of this packet Byte Bit Item Type Description 0 Subcode UINT8 0xA5 1 2 Mask 0 bit field 8F AB Primary Timing Information Reserved 8F AC Supplemental Timing Information Reserved Reserved Reserved Automatic Output Packets 3 4 Mask 2 bit field reserved Au BWN O Command Packet 0x8E A6 Self Survey Command Use command packet 8E A6 to issue a self survey command to save the current position in flash or to delete the position saved in flash There is no response to this packet Byte Item Type Value Meaning 0 Subcode UINT8 OxA6 1 Self survey command UINT8 0 Restart self survey 1 Save position to Flash 2 Delete position from Flash Command Packet 0x8E A9 Self Survey Parameters Use command packet 8E A9 to set the self survey parameters or to request the current settings The Resolution T replies to requests with response packet 8F A9 Data fields e Self Survey Enable Use this field to enabled or disabled the self survey mechanism 0 Disable the self survey mechanism 1 Enable the self survey mechanism e Position Save Flag
7. Use this field to tell the self survey mechanism to automatically save or to not save the self surveyed position at the end ofthe self survey procedure 0 Dont automatically save the surveyed position when the self survey is complete 1 Automatically save the surveyed position when the self survey is complete Resolution T GPS Embedded Board User Guide 73 A Trimble Standard Interface Protocol 74 e Self Survey Length Use this field to specify the number of position fixes that are to be averaged together to form the self surveyed position used for clock only fixes Limits 1 to 2 1 fixes Byte Item Type Value Description 0 Subcode UINT8 OxA9 1 Self Survey Enable UINT8 0 Disabled 1 Enabled 2 Position Save Flag UINT8 0 Don t save position 1 Save self surveyed position at the end of the survey 3 6 Self Survey Length UINT3 2 see above Number of fixes 7 10 Reserved UINT3 2 0 0 Report Packet 0x8F 01 Report Raw GPS Subframes TSIP super packet 0x8F 01 is used to report raw GPS subframes A report is sent for a specific SV with a specific GPS subframe based on the Operation selected using the command packet Ox8E 01 This packet may have different lengths depending on the value of the Status field If Status is 0 the packet consists of 45 bytes including all 10 subframe data words If Status is not 0 only the first 4 bytes are sent The data fields of this report packet following the packet ID Ox8F are as fol
8. When 0 UTC offset information has been received When 1 UTC offset information is not yet known Bit 4 When 0 time is coming from GPS When 1 the Resolution T is ina test mode and time is being generated by the test mode selected by the user See packet 8E A4 Test Modes Resolution T GPS Embedded Board User Guide 77 A Trimble Standard Interface Protocol Time of Day The time of day is sent in hours minutes seconds format and varies from 00 00 00 to 23 59 59 except when time is in UTC and a leap second insertion occurs In this case the time will transition from 23 59 59 to 23 59 59 to 00 00 00 Use command packet 8E A2 to select either the GPS or UTC time scale e Date The date is sent in day month year format Use command packet 8E A2 to select either the GPS or UTC time scale Broadcast Control Packet 8F AB Mask 0 Bit 0 Byte Bit Item Type Value Description 0 Subcode UINT8 OxAB 1 4 Time of week UINT32 GPS seconds of week 5 6 Week number UINT16 GPS week number see above 7 8 UTC Offset SINT16 UTC Offset seconds 0 Timing flag bit field 0 GPS time 1 UTC time 1 0 GPS PPS 1 UTC PPS 2 0 time is set 1 time is not set 3 0 have UTC info 1 no UTC info 4 0 time from GPS 1 time from user 10 Seconds UINT8 0 59 Seconds 11 Minutes UINT8 0 59 Minutes 12 Hours UINT8 0 23 Hours 13 Day of Month UINT8 1 31 Day of month 14 Month UINT8 1 12 Month of year 15 16 Year UINT16 Four digits of year for example 1998
9. clock etc This packet has variable length equal to 17 nsvs where nsvs is the number of satellites used in the solution If an SV is rejected for use by the T RAIM algoritm then the SV PRN value will be negative The GPS receiver sends this packet in response to packet 0x24 when the selection list is updated If enabled with packet 8E A5 the receiver will send this packet whenever the selection is updated The data format is shown below Byte Bit Item Type Value Meaning 0 0 2 fix dimension bit field 1 1D clock fix 3 2D fix 4 3D fix 5 OD clock fix 3 fix mode bit field 0 auto 1 manual 4 7 number of SVsin fix bit field 0 12 count 1 4 PDOP Single PDOP 5 8 HDOP Single HDOP 9 12 VDOP Single VDOP 13 16 TDOP Single TDOP 17 n SV PRN SINT8 1 32 PRN 64 Resolution T GPS Embedded Board User Guide Trimble Standard Interface Protocol A Report Packet 0x83 Double Precision XYZ This packet provides current GPS position fix in XYZ ECEF coordinates If the I O position option is set to XYZ ECEF and the I O double position option is selected the receiver sends this packet each time a fix is computed The data format is shown below Byte Item Type Units 0 7 X Double meters 8 15 Y Double meters 16 23 Z Double meters 24 31 clock bias Double meters 32 35 time of fix Single seconds Note The time of fix is in GPS time or UTC as selected by the I O timing option Packet 0x42 provides a single precision versio
10. the comma delineators to parse the NMEA message date field The following table specifies the definitions of all field types in the NMEA messages supported by Trimble Type Symbol Definition Status A Single character field A Yes data valid warning flag clear V No data invalid warning flag set Special Format Fields Latitude ILIN Fixed variable length field Degreesminutes decimal 2 fixed digits of degrees 2 fixed digits of minutes and a variable number of digits for decimal fraction of minutes Leading zeros always included for degrees and minutes to maintain fixed length The decimal point and associated decimal fraction are optional if full resolution is not required Resolution T GPS Embedded Board User Guide 85 NMEA 0183 Protocol Type Symbol Definition Longitude yyyyy yyy Fixed Variable length field Degreesminutes decimal 3 fixed digits of degrees 2 fixed digits of minutes and a variable number of digits for decimal fraction of minutes Leading zeros always included for degrees and minutes to maintain fixed length The decimal point and associated decimal fraction are optional if full resolution is not required Time hhmmss ss Fixed Variable length field hoursminutesseconds decimal 2 fixed digits of minutes 2 fixed digits of seconds and a variable number of digits for decimal fraction of seconds Leading zeros always included for hours minutes and seconds to maintain fixed length The decimal point a
11. 0x37 When a position fix is computed 0x56 Velocity ENU single precision 0x35 0x37 When a position fix is computed 0x58 Satellite system data none 0x38 When new system data is received 0x6D Satellite list DOPS mode none 0x24 When the satellite selection list is updated 0x83 Position XYZ ECEF double 0x35 0x37 When a position fix is computed precision 0x84 Position LLA double precision 0x35 0x37 When a position fix is computed Ox8F AB Primary timing packet Ox8E A5 none Once per second Ox8F AC Secondary timing packet Ox8E A5 none Once per second Resolution T GPS Embedded Board User Guide 41 A Trimble Standard Interface Protocol Customizing operations parameters The Resolution T provides a number of user configurable parameters that allow the user to customize the operation of the Resolution T These parameters are stored in flash memory to be retained during loss of power and through resets At reset or power up the Resolution T configures itself based on the parameters stored in the flash The user can change the values of these parameters to achieve the desired operation using a variety of TSIP packets The Resolution T configures itself based upon the new parameters immediately but the new parameter is not automatically saved to flash The user must direct the Resolution T to save the parameters to flash To change the parameter values stored in flash the user sends packet Ox8E 26 to direct the Resolution T to save the curre
12. 408 481 6940 24 hours a day or e mail your request to trimble_support trimble com Please be prepared to provide your name address and telephone numbers proof of purchase acopy of this Trimble warranty adescription of the nonconforming Product including the model number anexplanation of the problem 2 Resolution T GPS Embedded Board User Guide The customer service representative may need additional information from you depending on the nature ofthe problem Warranty Exclusions and Disclaimer This Product limited warranty shall only apply in the event and to the extent that a the Product is properly and correctly installed configured interfaced maintained stored and operated in accordance with Trimble s applicable operator s manual and specifications and b the Product is not modified or misused This Product limited warranty shall not apply to and Trimble shall not be responsible for defects or performance problems resulting from i the combination or utilization of the Product with hardware or software products information data systems interfaces or devices not made supplied or specified by Trimble ii the operation of the Product under any specification other than or in addition to Trimble s standard specifications for its products iii the unauthorized installation modification or use of the Product iv damage caused by accident lightning or other electrical discharge fresh or salt
13. 5 aos ee we wk oe A 9 CR RR 27 Neu PDT 28 Communicating with the receiver eee es 28 Software to0l8 Lac cala a hele POUR ie e asp edt Xd a we A 28 Port configuration 2 2 a 3325 hg enun Ba A o PR GR ake Ie qi ases in UR 28 Port protocol and data output options saae 29 Protocol configuration and interface 2 ee ee 29 NMEA 0183 Protocol and Data Output Options llle 30 System Operation 6 264 civ ee eet bene see RR Reo 31 Operation su soe imu ep ney We a a Bae AA oe Eee ed y 32 StartUp n on eth e ia ew o aes Wald eed a ale alae adhe ae ada ae 32 Automatic operatio sr oce ORE ERG hU aca RU de ON 32 Tracking modes 4e cre per eS R REA b ve Xu Gd e tas ees eed 33 PPS quantization ertor sios o vow coe nde Oed S BTA A e ee ed dU eod 34 Data COMMUNICATION umi sm Me RR RR on aA d RU d ee d Rh ea da eds 36 AAA sak a oak a ea R aAa a ia i aa ga aa aa ai A SE a aa aA 36 Tunng oprao eea Ga eoe oae E COR E EEE E 37 Using Resolution T in mobileapplications lees 37 Customizing Operations sa ssa sa ani aek e ACER OR ene e he aes Ah EAS ETUR TR d td 38 Configuration parameters x ces pasate ane oe PRED a e EE Ra RUE E RE s 38 System architeet re 2 uoa aise thle e e ace Ra Vote aee ea E EUR e LAMA Gece Rcs 39 Trimble Standard Interface Protocol 40 O 41 Interfaceseope 4s wacekWo a A hu eee eee See 41 Automatic output packets aaau aa 41 Customizing operations parameters eer
14. 84 NMEA 0183 message structure leen 85 Held Mentions eoa AAA vede eos eu i petes test s oa 85 NMEA 0183 message options s sas aer eee hn 86 NMEA 0183 message formats eee hrs 87 GGA GDPS Fix Data hi Sac ero Ex e de SO Up OY y rec wR wae 87 GLL Geographic Position Latitude Longitude lle 88 GSA GPS DOP and Active Satellites ee ee 88 GSV GPS Satellites in View o o o oooooooo ee ee 89 RMC Recommended Minimum Specific GPS Transit Data 04 89 VTG Track Made Good and Ground Speed 0 000 eee eee eee 90 ZDA Dime Date oue ces Hala ene o Ss eme ee ee a en o 90 Exception behaviors 2g ue pa Sad WEEE Ee Ge Pe dc eae ww pw mdp 91 Interruption of GPS signal lees 91 cU lcg bcc bce he ee we OS RS ee ha Mew Hem eae 92 Mechanical specification celer 93 Resolution T GPS Embedded Board User Guide Introduction In this chapter Operation Timing features Starter kit Use and care Technical assistance Your comments CHAPTER The Resolution T GPS Embedded Board User Guide describes how to integrate and operate the Resolution T GPS timing receiver The instructions in this manual assume that you know how to use the primary functions of a Microsoft Windows operating system The Trimble Resolution T embedded timing board is a full featured 12 channel parallel tracking GPS receiver The receiver is designed to operate on the L1 1575
15. Configuration TSIP packet OxBC is used to set and query the port characteristics In query mode packet OxBC is sent with a single data byte and returns report packet OxBC Note The input and output baud rates must be the same Byte Item Type Value Meaning 0 Port Number UINT8 0 Port 1 standard 1 Port 2 not available FF Current port Field data format The table below lists the individual fields within the packet OxBC when used in the set mode and when read in the query mode Byte Item Type Value Meaning 0 Port to Change UINT8 0 Port 1 standard 1 Port 2 factory only OxFF Current port 1 Input Baud Rate UINT8 0 None 1 None 2 300 baud 3 600 baud 4 1200 baud 5 2400 baud 6 4800 baud 7 9600 baud 8 19200 baud 9 38400 baud 10 57600 baud 11 115200 baud 2 Output Baud Rate UINT8 As above As above 3 Data Bits UINT8 2 7 bits 3 8 bits 4 Parity UINT8 0 None 1 Odd 2 Even Resolution T GPS Embedded Board User Guide 67 A Trimble Standard Interface Protocol Byte Item Type Value Meaning 5 Stop Bits UINT8 0 1 bit 1 2 bits Flow Control UINT8 0 none Input Protocols UINT8 0 none 2 TSIP 8 Output Protocols UINT8 0 none 2 TSIP 4 NMEA 9 Reserved UINT8 0 TSIP Superpackets 68 Several packets have been added to the core TSIP protocol to provide additional capability for the receivers In packets Ox8E and their 0x8F responses the first data byte is a subcode which indicates the superpacket type
16. Description 1 3 14 15 16 17 hh Mode M Manual A Automatic In manual mode the receiver is forced to operate in either 2D or 3D mode In automatic mode the receiver is allowed to switch between 2D and 3D modes subject to the PDOP and satellite masks Current Mode 1 fix not available 2 2D 3 3D PRN numbers of the satellites used in the position solution When less than 12 satellites are used the unused fields are null Position dilution of precision PDOP Horizontal dilution of precision HDOP Vertical dilution of precision VDOP Checksum Resolution T GPS Embedded Board User Guide NMEA 0183 Protocol B GSV GPS Satellites in View The GSV message identifies the GPS satellites in view including their PRN number elevation azimuth and SNR value Each message contains data for four satellites Second and third messages are sent when more than 4 satellites are in view Fields 1 and 2 indicate the total number of messages being sent and the number of each message respectively SGPGSV X X XX XX XX XXX XX XX XX XXX XX XX XX XXX XX XX XX XXX xx hh lt CR gt lt LF gt Field number Description 14 Total number of GSV messages s s Message number 1 to 3 Total number of satellites in view Satellite PRN number Satellite elevation in degrees 90 Maximum Satellite azimuth in degrees true 000 to 359 7 Satellite SNR C No null when not tracking 8 9 10 11 P
17. Ox8F 01 Report Raw GPS Subframes 0 000000 74 Report Packet 0x8F 15 Current Datum Values 1 0 0 0 eee eee eee ee 75 Report Packet 0x8F 41 Stored Manufacturing Operating Parameters 75 Report Packet Ox8F 42 Stored Production Parameters o o oooooo oo 76 Report Packet 0x8F 4A Set PPS Characteristics o o o oooooooo ee ee 76 Report Packet Ox8F 4E PPS Output llle 76 Report Packet 0x8F A2 UTC GPS Timing lee 76 Report Packet 0x8F A5 Packet Broadcast Mask 00 000 ee eee 76 Report Packet Ox8F A9 Self Survey Parameters 0 00 eee eee eee 77 Report Packet Ox8F AB Primary Timing Packet 0 0 00 00 ooo 77 Broadcast Control Packet 8F AB Mask 0 BitO 2 2 eee eee 78 Report Packet Ox8F AC Supplemental Timing Packet lere 78 Unused or miscellaneous packets 2 2 2 ee ee eee 82 Report Packet 0x13 Unparsable Packet 1 2 0 llle 82 Report Packet 0x13 Data Format eee 82 Legacy packets unused 0 0 0 ee et res 82 Report Packet Ox54 Bias and Bias Rate 1 2 lees 82 Report Packet Ox46 Health of Receiver llle 82 Report Packet Ox41 GPS Time llle 82 Report Packet 0x4B Machine Code ID and Additional Status 82 NMEA 0183 Protocol caso oh n ohm RA Cx RR Rn 83 Introduction cats exer Eee QE EUER ket dr pe De d P dou d gd oe ee ie A 84 NMEA 0183 communication interface oaaae
18. The Resolution T GPS receiver is ready to accept TSIP commands approximately 2 1 seconds after power up If a command is sent to the receiver within this 2 1 second window the receiver will ignore the command The Resolution T GPS receiver will not respond to commands sent within the 2 1 second window and will discard any associated command data WARNING Operating or storing the Resolution T GPS timing receiver outside the specified temperature range can damage it For more information see the product specifications on the data sheet Routing any cable A CAUTION Be careful not to damage the cable Take care to avoid sharp bends or kinks in the cable hot surfaces for example exhaust manifolds or stacks rotating or reciprocating equipment sharp or abrasive surfaces door and window jambs and corrosive fluids or gases Resolution T GPS Embedded Board User Guide 3 Safety Information AC adaptor safety 4 A An international adaptor kit is provided with the Resolution T Starter Kit WARNING Using an incorrect AC adaptor can damage your product and may void your warranty To use AC adaptors safely Use only the AC adaptor intended for the Resolution T GPS timing receiver Using any other AC adaptor can damage your product and may void your warranty Do not use the AC adaptor with any other product Make certain that the input voltage on the adaptor matches the voltage and frequency in your location Make cert
19. about Last Computed Fix This packet provides information concerning the time and origin of the previous position fix The receiver sends this packet among others in response to packet 0x37 The data format is shown below Byte Item Type Value Meaning 0 source of info UINT8 none regular fix initialization diagnostic initialization diagnostic entered by 0x23 or 0x2B entered by 0x31 or 0x32 0 1 2 4 5 6 8 default after BBRAM fail 0 1 2 3 4 5 6 1 Tracking mode UINT8 No previous fix Time only SV 2D clock hold 2D 3D overdetermined clock DGPS reference 2 5 time of last fix Single seconds GPS time 6 7 week of last fix UINT16 weeks Report Packet 0x58 GPS System Data Acknowledge from Receiver This packet provides GPS data almanac ephemeris etc The receiver sends this packet in response to packet 0x38 The data format is shown below The table and section numbers referred to in the Meaning column reference the Global Positioning System Standard Positioning Service Signal Specification document Data Format Byte Item Type Value Meaning 0 operation UINT8 2 data out 3 no data on SV 1 Type of data UINT8 2 Almanac 3 Health page T_oa WN_oa 4 lonosphere 5 UTC 6 Ephemeris 2 Sat PRN UINT8 0 Data that is not satellite ID specific 1 to 32 Satellite PRN number 3 Length n UINT8 Byte count 4ton 3 Data UINT8 Table 2 8 Note If data is not available byte 3 is set to 0 and no data
20. field Bit 0 not used Bit 1 Antenna open Bit 2 Antenna shorted Bit 3 Not tracking satellites Bit 4 not used Bit 5 Survey in progress Bit 6 no stored position Bit 7 Leap second pending Bit 8 In test mode Bit 9 Position is questionable Bit 10 not used Bit 11 Almanac not complete Bit 12 PPS was generated 12 GPS Decoding UINT8 0 Doing fixes Status 1 Don t have GPS time 3 PDOP is too high 8 No usable sats 9 Only 1 usable sat 0x0A Only 2 usable sats 0x0B Only 3 usable sats 0x0C The chosen sat is unusable 0x10 TRAIM rejected the fix 13 Reserved UINT8 0 Reserved 14 Spare Status 1 UINT8 0 15 Spare Status 2 UINT8 0 16 19 Local clock bias Single ns 20 23 Local clock bias rate Single ppb 24 27 Reserved UINT32 Reserved 28 31 Reserved Single Reserved 32 35 Temperature Single degrees C 36 43 Latitude Double radians 44 51 Longitude Double radians 52 59 Altitude Double meters 60 63 PPS Quantization Single seconds Error 64 67 Spare Future expansion Resolution T GPS Embedded Board User Guide 81 A Trimble Standard Interface Protocol Unused or miscellaneous packets Report Packet 0x13 Unparsable Packet This packet is sent in response to a received packet that was unparsable A packet is unparsable if the packet ID is not recognized or if the length or content of the packet is not correct for the packet ID Report Packet 0x13 Data Format Byte Type Item 0 UINT8 Packet ID of unparsable packet 1 N UINT8 Packet data by
21. hour UINT8 0 23 Hour of the board s build date 11 12 Hardware code INT16 Any Hardware code associated with Hardware ID 13 Length of UINT8 Any The length of the Hardware ID L Hardware ID 14 13 L Hardware ID UINT8 String Hardware ID string in ASCII Command Packet 0x1E Clear RAM then Reset This packet commands the Resolution T to perform either a cold reset warm reset or a factory reset A cold reset will clear the GPS data almanac ephemeris etc stored in RAM and is equivalent to a power cycle A factory reset will additionally restore the factory defaults of all configuration parameters stored in flash memory 48 Resolution T GPS Embedded Board User Guide Trimble Standard Interface Protocol A Awarm reset clears ephemeris and oscillator uncertainty but retains the last position time and almanac This packet contains one data byte The data format is shown below Byte Item Type Value Meaning 0 Reset UINT8 Ox4B Cold reset OxOE Warm reset 0x46 Factory reset Note The factory reset command will delete the stored position and cause self survey to restart Command Packet 0x1F Request Software Version This packet requests information about the version of software in the Resolution T This packet contains no data The GPS receiver returns packet 0x45 Command Packet 0x24 Request GPS Satellite Selection This packet requests a list of satellites used for the current position time fix This
22. is sent Resolution T GPS Embedded Board User Guide 59 A Trimble Standard Interface Protocol Almanac data type 2 Byte Item Type Value Meaning 4 Toa raw UINT8 Table 2 8 5 SV_HEALTH Single 6 9 e Single 10 13 toa Single 14 17 ig Single 18 21 OMEGADOT Single 22 25 sqrt A Single 26 29 OMEGA O Single 30 33 OMEGA Single 34 37 Mo Single 38 41 afo Single 42 45 af Single 46 49 Axis Single 50 53 n Single 54 57 OMEGA_n Single Derived 58 61 ODOT_n Single Derived 62 65 toc UINT16 time of collection set to 1 0 if there is no data available 66 67 week number UINT16 GPS week number 68 69 WNa UINT16 Sec 2 4 5 2 3 Note All angles are in radians Almanac health data type 3 Byte Item Type Meaning 4 week number for health UINT8 Sec 2 4 5 3 5 36 SV health UINT8 Sec 2 4 5 3 37 toa for health UINT8 Sec 2 4 5 2 3 38 current toa UINT8 time of collection 39 40 current week number UINT16 time of collection lonosphere data type 4 Byte Item Type Meaning 4 11 not used 12 15 Oo Single Sec 2 4 5 6 16 19 04 Single 20 23 0 Single 24 27 Q3 Single 28 31 Bo Single 60 Resolution T GPS Embedded Board User Guide Trimble Standard Interface Protocol A Byte Item Type Meaning 32 35 B Single 36 39 B2 Single 40 43 B3 Single UTC data type 5 Byte Item Type Meaning 4 16 not used 17 24 Ao Double Sec 2 4 5 5 25 28 A4 Single 29 30 AtLS SINT16 31 34 tot Single 35 36 WN UINT16 37 38 WN s
23. least three satellites are tracking PPS is generated every second 130 PPS is always on PPS is generated every even second 131 PPS is output when at least one satellite is tracking PPS is generated every even second 132 PPS is output when at least three satellites are tracking PPS is generated every even second Command Packet 0x8E A2 UTC GPS Timing Command packet 8E A2 sets the UTC GPS timing mode time and date fields in packet 0x8F AB and the temporal location of the Resolution T output PPS Send packet 8E A2 with no data to request the current settings The Resolution T replies with response packet 8F A2 Byte Bit Item Type Value Meaning 0 Subcode UINT8 0xA2 1 01 UTC GPStime bitfield bit field 0 GPS time date in packet Ox8F AB UTC time date in packet Ox8F AB PPS referenced to GPS time PPS referenced to UTC time O Resolution T GPS Embedded Board User Guide Trimble Standard Interface Protocol A Command Packet 0x8E A4 Test Modes The Resolution T provides a test mode of operation that allows the user to set the time and UTC parameters Packet 0x8F AC provides a status bit minor alarm bit 8 to warn the user that the Resolution T is operating in a test mode There is no response to this packet Note that test mode 3 does not actually cause the Resolution T to enter a test mode but instead provides a means for the user to send UTC parameters to the Resolution T that will be used in test mode 1
24. mask to 4 or higher minimizes the impact of multi reflected signals PDOP mask Position Dilution of Position PDOP is a measure of the error caused by the geometric relationship of the satellites used in the position solution Satellite sets that are tightly clustered or aligned in the sky have a high PDOP and contribute to lower position accuracy For timing applications a PDOP mask of 12 offers a satisfactory trade off between accuracy and GPS coverage With worldwide GPS coverage the PDOP mask can be lowered even more for many applications without sacrificing coverage Note PDOP is only applicable during self survey or whenever the receiver is performing position fixes Tracking modes The Resolution T operates in one of two main fix modes Self Survey Position fix mode e Overdetermined Clock mode After establishing a reference position in Self Survey mode the Resolution T automatically switches to Overdetermined OD Clock mode Self Survey mode At power on the Resolution T performs a self survey by averaging 2000 position fixes The number of position fixes until survey completion is configurable using the 8E A9 command The default mode during self survey is 3 D manual where the receiver must obtain a 3 D solution with a PDOP below the PDOP mask The PDOP mask criteria can be set and queried using a TSIP packet If fewer than four conforming satellites are visible the Resolution T suspends the self survey The hig
25. per second PPS The receiver provides a 1 0 millisecond wide CMOS compatible Pulse Per Second PPS The PPS is a positive pulse available on the connector ofthe interface unit The rising edge of the pulse is synchronized to GPS The timing accuracy is 15 nanoseconds 1 6 when operating in the Overdetermined Timing Mode The rising edge ofthe pulse is less than 20 nanoseconds The PPS is capable of driving aload up to 5mA without damaging the receiver The PPS signal is defaulted to always output This is a customer selectable feature under TSIP packet 8F 4E Other options include PPS output when one or more satellites are usable or when three or more satellites are usable Additionally the PPS output can be programmed to provide an Even Second output using TSIP packet 8F 4E The Resolution T GPS receiver is designed for embedded applications and requires a regulated 3 3 VDC input 43 0 to 43 6 VDC The receiver provided in the Starter Kit is installed on a motherboard which provides a DC power regulator which converts a 9 VDC to 32 VDC input to the regulated 3 3 VDC required by the receiver and the regulated 5 VDC required by the antenna Power can be applied to the interface unit using the AC DC power converter AC DC power converter The AC DC power converter may be used as an alternate power source for the interface unit The AC DC power converter converts 110 or 220 VAC to a regulated 24 VDC compatible with the interface unit T
26. process and limited warranty Receipt of software Fixes or other enhancements shall not serve to extend the limited warranty period For purposes of this warranty the following definitions shall apply 1 Fix es means an error correction or other update created to fix a previous software version that does not substantially conform to its Trimble specifications 2 Minor Update occurs when enhancements are made to current features in a software program and 3 Major Upgrade occurs when significant new features are added to software or when a new product containing new features replaces the further development of a current product line Trimble reserves the right to determine in its sole discretion what constitutes a Fix Minor Update or Major Upgrade Warranty Remedies Ifthe Trimble Product fails during the warranty period for reasons covered by this limited warranty and you notify Trimble of such failure during the warranty period Trimble will repair OR replace the nonconforming Product with new equivalent to new or reconditioned parts or Product OR refund the Product purchase price paid by you at Trimbles option upon your return of the Product in accordance with Trimble s product return procedures then in effect How to Obtain Warranty Service To obtain warranty service for the Product please contact your local Trimble authorized dealer Alternatively you may contact Trimble to request warranty service at 1
27. provides current GPS velocity fix in XYZ ECEF coordinates If the I O velocity option packet 0x35 is set to XYZ ECEF then the GPS receiver sends this packet each time a fix is computed or in response to packet 0x37 The data format is shown below The time of fix is in GPS or UTC as selected by the I O timing option Byte Item Type Units 0 3 X velocity Single meters second 4 7 Y velocity Single meters second 8 11 Z velocity Single meters second 12 15 bias rate Single meters second 16 19 time of fix Single seconds Resolution T GPS Embedded Board User Guide 55 A Trimble Standard Interface Protocol Report Packet 0x45 Software Version Information This packet provides information about the version of software in the Resolution T The GPS receiver sends this packet after power on and in response to packet Ox1F Byte Item Type 0 Major version number of application UINT8 1 Minor version number UINT8 2 Month UINT8 3 Day UINT8 4 Year number minus 1900 UINT8 5 Major revision number of GPS core UINT8 6 Minor revision number UINT8 7 Month UINT8 8 Day UINT8 9 Year number minus 1900 UINT8 Note Bytes 0 though 4 are part of the application layer of the firmware while bytes 5 through 9 are part of the GPS core layer of the firmware Report Packet 0x47 Signal Level for All Satellites Tracked This packet provides received signal levels for all satellites currently being tracked or on which tracking is being atte
28. signal If the GPS signal is interrupted temporarily the NMEA will continue to be output according to the user specified message list and output rate Position and velocity fields will be blank until the next fix but most other fields will be filled Resolution T GPS Embedded Board User Guide 91 APPENDIX Specifications In this chapter The Resolution T is designed for a variety of embedded timing applications This appendix includes the system specifications and mechanical drawings for the Resolution T and the available GPS antenna W Mechanical specification Resolution T GPS Embedded Board User Guide 92 C Specifications Mechanical specification 0 811 0 2 20 60 KEEP OUT AREA al Q25 6 35 SO TOP amp BOTTOM NOTES 1 RF CONNECTOR SMB J4 8 PIN 1 0 CONNECTOR 2X4 2mm Samtec TMM 104 01 T D SM ou ovi HS vaa 93 Resolution T GPS Embedded Board User Guide C Specifications 94 Resolution T GPS Embedded Board User Guide NORTH AMERICA Trimble Navigation Limited Corporate Headquarters 935 Stewart Drive Sunnyvale CA 94085 1 800 787 4225 1 408 481 7741 NZ The right one EUROPE Trimble Navigation Europe Phone 49 6142 2100 161 KOREA Trimble Export Ltd Korea Phone 82 2 555 5361 CHINA Trimble Navigation Ltd China Phone 86 21 6391 7814 TAIWAN Trimble Navigation Taiwan Phone 886 02 85096574 Trimble www trimble co
29. softwares usus cdo bli a E a oe we cd 13 Removing the Resolution T module from the motherboard 0 13 Timing receiver performance leer 14 Interface protocols se re een Ed a EX UR Go Pea Pe a aa 15 Resolution T starter Ki 4s uode IR as e do RUNE ese UR d 15 Starter kitinterface Unit sss 2d e e Ge bee Dux LARA OA ek i 16 POWER gauge a Ru ROREM MUR Ra er HE RON EDS EG ERREUR UE PUR pope o qua 18 AC DC power converter esee hr 18 Setting lip the Starter Kit us Ed ee ee Ye a Y ede Yd 19 Setting up the software toolkit llle 20 3 Hardware Integrati0M lt lt lt lt lt 22 Resolution T board i ae taa ate e Mea Aad ee aA ee eA aoe eo de 23 ConDnBeclOIS sm A ee Pe REPS Reed Rp dc p d OUR bk pe m ee ee 23 Digital IO Power connector lesen 23 Mating connectors se e m oem moror eR I E US Oh RUNE E Re Dente Pn 23 RE conHector 222g ka A Cao Ru Wo ea xU OO oy Wo d Ue XO ER RARE 23 Antenna opos ce a OR ch e deg d dcs y OR hom Bee Rok RC dod 24 Digital IO Power connector pin out ia acea esce ran A EES ERD 24 Powerrequireimehts ege o eee RU p hot gm o A PR RR CR PCR wl Rn 24 Serial IHLePIaee eoru ocu dod gabe x E e vg qe S Ple deed WT quee E aha d 25 Pulse per second PPS cesse ee ee rs 25 ning C 25 Resolution T GPS Embedded Board User Guide 5 Contents 6 GPS antennia ando eps preto pei here oi ad yo dette Sb redd 25 Software Interface
30. starter kit and how to set it up The hardware integration is described in Chapter 3 Hardware Integration Resolution T GPS Embedded Board User Guide 12 Setting up the Resolution T Starter Kit 2 System requirements Hardware The Trimble Resolution T Starter Kit see page 15 e User provided connectors and extension cords to connect the Resolution T to the computer antenna interface and other devices as required e 24 VDC power supply e User provided equipment to analyze the 10 MHz output frequency and the 1 PPS accuracy and a BNC connector to connect them to the Resolution T module e User provided connectors and extension cords to connect the Resolution T to the computer antenna interface and other devices as required Computer Anoffice computer running a version of the Windows operating system Windows 2000 or later The computer must have one of the following service packs installed Service Pack 2 for Windows Vista or Windows XP Service Pack 4 for Windows 2000 System software e Monitor software The software is used to monitor the GPS performance of the Resolution T and to change its settings The software is compatible with the Windows 95 98 2000 and XP operating systems and with the Windows Vista operating system e Trimble Standard Interface Protocol TSIP This consists of command packets and report packets See Appendix A Trimble Standard Interface Protocol Removing the Re
31. the ability to communicate with the receiver e g selecting the PC COM port settings that do not match the receiver s or changing the output protocol to TSIP while not using TSIPCHAT Port protocol and data output options Protocol configuration and interface The factory default protocol for the Resolution T GPS receiver is the Trimble Standard Interface Protocol TSIP for both input and output The serial port setting is 9600 baud 8 odd 1 The receiver protocol can be re configured using TSIP command packet OxBC DSP Monitor or a user written serial interface program DSP Monitor DSPMon exe a Windows based GUI provides a versatile graphical interface for monitoring TSIP data This application allows the user to view complete receiver operations including data output status and configuration In this application the entry of command packets is replaced by traditional point and click pull down menus C source code examples for TSIP commands are also provided in Appendix A Trimble Standard Interface Protocol When used as software design templates this source code can significantly speed up code development The protocol settings and options are stored in Random Access Memory RAM They can be saved into the non volatile memory flash if required using command Ox8E 26 Resolution T GPS Embedded Board User Guide 29 4 30 Software Interface NMEA 0183 Protocol and Data Output Options The National Marine Electronic
32. the survey as a percentage of fixes collected so far The self survey will be complete when the self survey progress reaches 100 percent Minor Alarms This field is bitwise encoded with several minor alarm indicators A minor alarm indicates a condition that the user should be alerted to but does not indicate an immediate or necessarily any impairment of functionality For each bit a value of 0 means that the condition is not indicated Bits not described below should be ignored Bit 1 When 1 indicates that the antenna input connection is open More precisely this bit indicates that the antenna input is not drawing sufficient current Normally the Resolution T provides power to the antennas LNA Low Noise Amplifier through the center conductor of the antenna cable On board circuitry senses this current draw and if low this condition will be indicated However when the antenna is powered elsewhere e g when using a splitter then an antenna open condition is expected and does not imply a fault nor does it impair the operation of the Resolution T Bit2 When I indicates that the antenna input is shorted More precisely this bit indicates that the antenna input is drawing too much current Onboard protection circuitry prevents any damage to the Resolution T when its antenna input is shorted to ground This condition tends to indicates a fault in either the antenna cable or the antenna itself Bit 3 When 1 indicates that no s
33. to save the position Note When converting from degrees to radians use the following value for PI 3 1415926535898 Single precision data format Byte item Type Units 0 3 Latitude Single Radians north 4 7 Longitude Single Radians east 8 11 Altitude Single Meters Double precision data format Byte Item Type Units 0 7 Latitude Double Radians north 8 15 Longitude Double Radians east 16 23 Altitude Double Meters Command Packet 0x34 Satellite Select For One Satellite Mode This packet allows the user to control the choice of the satellite to be used for the one satellite time only fix mode This packet contains one byte If the byte value is 0 the GPS receiver automatically chooses the best This automatic selection of the best satellite is the default action and the GPS receiver does this unless it receives this packet Ifthe byte value is from 1 to 32 the packet specifies the PRN number of the satellite to be used Command Packet 0x35 Set or Request I O Options This packet requests the current I O option states and allows the I O option states to be set as desired Resolution T GPS Embedded Board User Guide 51 A Trimble Standard Interface Protocol To request the option states without changing them the user sends this packet with no data bytes To change any option states the user includes 4 data bytes with the values The I O options their default states and the byte values for all possible state
34. to the overdetermined timing mode Note that this position is not automatically saved to flash memory If you want to save this position first set the position wait at least 2 seconds and then use packet 8E A6 to save the position Single precision data format Byte Item Type Units 0 3 X axis Single Meters 4 7 Y axis Single Meters 8 11 Z axis Single Meters Double precision data format Byte Item Type Units 0 7 X axis Double Meters 8 15 Y axis Double Meters 16 23 Z axis Double Meters 50 Resolution T GPS Embedded Board User Guide Trimble Standard Interface Protocol A Command Packet 0x32 Accurate Initial Position Latitude Longitude Altitude This packet provides an accurate initial position to the GPS receiver in latitude longitude and altitude coordinates Either the single precision or the double precision version of this packet may be used however we recommend using the double precision version for greatest accuracy The GPS receiver uses this position for performing time only fixes Ifa survey is in progress when this command is issued the survey is aborted and this position data is used immediately The coordinates entered must be in the WGS 84 datum The Resolution T will automatically switch to the overdetermined timing mode Note that this position is not automatically saved to flash memory If you want to save this position first set the position wait at least 2 seconds and then use packet 8E A6
35. water immersion or spray outside of Product specifications or exposure to environmental conditions for which the Product is not intended v normal wear and tear on consumable parts e g batteries or vi cosmetic damage Trimble does not warrant or guarantee the results obtained through the use of the Product or that software components will operate error free NOTICE REGARDING PRODUCTS EQUIPPED WITH TECHNOLOGY CAPABLE OF TRACKING SATELLITE SIGNALS FROM SATELLITE BASED AUGMENTATION SYSTEMS SBAS WAAS EGNOS AND MSAS OMNISTAR GPS MODERNIZED GPS OR GLONASS SATELLITES OR FROM IALA BEACON SOURCES TRIMBLE IS NOT RESPONSIBLE FOR THE OPERATION OR FAILURE OF OPERATION OF ANY SATELLITE BASED POSITIONING SYSTEM OR THE AVAILABILITY OF ANY SATELLITE BASED POSITIONING SIGNALS THE FOREGOING LIMITED WARRANTY TERMS STATE TRIMBLES ENTIRE LIABILITY AND YOUR EXCLUSIVE REMEDIES RELATING TO THE TRIMBLE PRODUCT EXCEPT AS OTHERWISE EXPRESSLY PROVIDED HEREIN THE ODUCT AND ACCOMPANYING DOCUMENTATION AND MATERIALS ARE OVIDED AS IS AND WITHOUT EXPRESS OR IMPLIED WARRANTY OF ANY KIND BY EITHER TRIMBLE OR ANYONE WHO HAS BEEN INVOLVED IN ITS CREATION PRODUCTION INSTALLATION OR DISTRIBUTION INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE TITLE AND NONINFRINGEMENT THE STATED EXPRESS WARRANTIES ARE IN LIEU OF ALL OBLIGATIONS OR LIABILITIES ON THE PART OF TRIMBLE ARISING OUT OF OR
36. 42 Factory default settings creara artera aeee eee 42 Packet 1 0 CONO 4 acu ac Pine ade ee RI AAA e ER 43 Serial port configuration lees 43 Tonm onu a PORCINO E E weet ERR Ai make EE E aay E e Bore 43 Accurate positione cis Re Wr aces ed WO Oe ee De be Sead x EX 43 A s beth d scena o red dx n o acid s bah erate hE gia e nob tad 44 Packets outputatstartup seem rs 44 Report packets Resolution T to User 1 2 llle 44 Command Packets User to Resolution TT onau anaua 45 Packet structure suae Gaede eem ba BASES GR ee ea eee Oe Ea be Pha E E Ee 46 Packet d scripBionss auss y reo ERR hx e ce AS A ea gs oe D dec 47 Command Packet Ox1C Firmware Version01 llle 47 Report Packet 0x1C 81 a soka odes boe cce donde ae a ace e eC e AR e aldo 47 Command Packet 0x1C 03 hardware component version information 48 Report Packet 0x1C 83 hardware component version information 48 Resolution T GPS Embedded Board User Guide Contents Command Packet OxlE Clear RAM then Reset 0000 e ooo 48 Command Packet Ox1F Request Software Version 0 00 e eee eee 49 Command Packet 0x24 Request GPS Satellite Selection 49 Command Packet 0x25 Initiate Hot Reset amp Self Test o o o oooo o 50 Command Packet 0x27 Request Signal Levels o o o o ooooooo o oo 50 Command Packet 0x31 Accurate Initial Position XYZ Cartesian ECEF 50 Command
37. 42 MHz frequency providing standard position service SPS using Coarse Acquisition C A code The Trimble Resolution T is designed for 3 3 V prime power and provides a separate pin on the I O connector for powering the antenna with a user supplied voltage from 3 0 V to 5 5 V antenna dependent For more information on GPS go to http www trimble com gps index shtml Resolution T GPS Embedded Board User Guide 9 1 Introduction Operation The Resolution T automatically initiates a self survey upon acquisition of GPS satellites When the survey is completed the receiver switches into the Overdetermined Timing Mode In this mode the reference position from the self survey is maintained in memory and the receiver solves only for clock error and clock bias The receiver provides for both Position and Time Receiver Autonomous Integrity Monitoring which allows the receiver to self determine a position change or to remove a satellite providing incorrect information from the timing solution Note To offset the delay inherent in the RF cable from the antenna to the receiver and further improve the accuracy determine the length of the cable and enter the offset based on the specific cable type Timing features The timing features of the Resolution T GPS timing receiver include the following e Automatic self survey Overdetermined timing mode e Single satellite timing mode e Timing Superpackets e TRAIM Timing Receiver Autonomous
38. A on Resolution T GPS Embedded Board User Guide 57 A Trimble Standard Interface Protocol Byte Data Type Bit Default Value Meaning Associated Packet 2 0 0 HAE datum Ox4A or 0x84 1 MSL geoid 3 0 0 reserved 4 0 single precision position 0x42 4A 1 double precision position 0x83 84 5 7 reserved 1 UINTS velocity 0 0 ECEF off 0x43 1 ECEF on 1 1 0 ENU off 0x56 1 ENU on 2 7 reserved 2 UINT8 timing 0 0 GPS time reference 0x42 0x43 0x4A 0x83 1 UTC time reference 0x84 0x56 3 UINT8 auxiliary 0 0 0 packet 5A off Ox5A 1 packet 5A on 1 0 0 raw PR s in 5A 0x5A 1 filtered PR s in 5A reserved 0 0 output AMU 0x5A 0x5C 0x47 1 output dB Hz 4 7 reserved 0 0 Report Packet 0x56 Velocity Fix East North Up ENU If East North Up ENU coordinates have been selected for the I O velocity option the receiver sends this packet under the following conditions Each time that a fix is computed In response to packet 0x37 last known fix The data format is shown below Byte Item Type Units 0 3 East Velocity Single m s for east for west 4 7 North Velocity Single m s for north for south 8 11 up velocity Single m s for up for down 12 15 clock bias rate Single m s 16 19 time of fix Single seconds Note The time of fix is in GPS or UTC time as selected by the I O timing option 58 Resolution T GPS Embedded Board User Guide Trimble Standard Interface Protocol A Report Packet 0x57 Information
39. IN CONNECTION WITH ANY PRODUCT BECAUSE SOME STATES AND JURISDICTIONS DO NOT ALLOW LIMITATIONS ON DURATION OR THE EXCLUSION OF AN IMPLIED WARRANTY THE ABOVE LIMITATION MAY NOT APPLY OR FULLY APPLY TO YOU Limitation of Liability TRIMBLE ENTIRE LIABILITY UNDER ANY PROVISION HEREIN SHALL BE LIMITED TO THE AMOUNT PAID BY YOU FOR THE PRODUCT TO THE MAXIMUM EXTENT PERMITTED BY APPLICABLE LAW IN NO EVENT SHALL TRIMBLE OR ITS SUPPLIERS BE LIABLE FOR ANY INDIRECT SPECIAL INCIDENTAL OR CONSEQUENTIAL DAMAGE WHATSOEVER UNDER ANY CIRCUMSTANCE OR LEGAL THEORY RELATING IN ANYWAY TO THE ODUCTS SOFTWARE AND ACCOMPANYING DOCUMENTATION AND MATERIALS INCLUDING WITHOUT LIMITATION DAMAGES FOR LOSS OF BUSINESS PROFITS BUSINESS INTERRUPTION LOSS OF DATA OR ANY OTHER ECUNIARY LOSS REGARDLESS OF WHETHER TRIMBLE HAS BEEN ADVISED OF THE POSSIBILITY OF ANY SUCH LOSS AND REGARDLESS OF THE COURSE OF DEALING WHICH DEVELOPS OR HAS DEVELOPED BETWEEN YOU AND TRIMBLE BECAUSE SOME STATES AND JURISDICTIONS DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES THE ABOVE LIMITATION MAY NOT APPLY OR FULLY APPLY TO YOU PLEASE NOTE THE ABOVE TRIMBLE LIMITED WARRANTY PROVISIONS WILL NOT APPLY TO PRODUCTS PURCHASED IN THOSE JURISDICTIONS E G MEMBER STATES OF THE EUROPEAN ECONOMIC AREA IN WHICH PRODUCT WARRANTIES ARE THE RESPONSIBILITY OF THE LOCAL TRIMBLE AUTHORIZED DEALER FROM WHOM THE PRODUC
40. Integrity Monitoring e Position integrity e Cable delay compensation e Accuracy 15 ns 10 Starter kit The starter kit makes it simple to evaluate the Resolution T receivers performance It can be used as a platform for configuring the receiver software or as a platform for troubleshooting your design For a complete description of the starter kit see Resolution T starter kit page 15 Use and care The Resolution T GPS timing receiver is a high precision electronic instrument and should be treated with reasonable care AN CAUTION There are no user serviceable parts inside the Resolution T and any modification to the unit by the user voids the warranty 10 Resolution T GPS Embedded Board User Guide Introduction 1 Technical assistance If you have a problem and cannot find the information you need in the product documentation contact the Trimble Technical Assistance Center at 800 767 4822 or email trimble_support trimble com Your comments Your feedback about the supporting documentation helps us to improve it with each revision Email your comment to techpubs trimble co nz Resolution T GPS Embedded Board User Guide 11 CHAPTER Setting up the Resolution T Starter Kit In this chapter System requirements Timing receiver performance Interface protocols Resolution T starter kit Power Setting up the starter kit Setting up the software toolkit This chapter describes the elements of the Resolution T
41. L l l l po 3L r L su 38540 80 90 100 50 60 70 40 Time seconds 20 30 10 35 Resolution T GPS Embedded Board User Guide 5 System Operation Data communication 36 The Resolution T outputs TSIP super packets or NMEA messages Immediately following power on the Resolution T outputs packets 8F AB 8F AC and PPS Use packet 8E A5 to enable or disable timing packets and automatic output packets These packets are described in Appendix A Trimble Standard Interface Protocol The factory default port setting is 9600 baud in out 8 data bits odd parity 1 stop bit The serial port setting can be changed and stored in flash memory using a TSIP command This port can be configured to transmit timing packets using packet 8E A5 GPS timing For many timing applications such as time frequency standards site synchronization systems and wireless voice and data networks the Resolution T can be used to steer a local reference oscillator The steering algorithm combines the short term stability of the oscillator with the long term stability of the GPS PPS An accurate GPS PPS allows the use of cost effective crystal oscillators which have less stability than expensive high quality oscillators such as OCXOs Oven Controlled Crystal Oscillators The GPS constellation consists of at least 24 orbiting satellites Unlike most telecommunications satellites GPS s
42. OG SGPVTG x x T x x M x x N x x K i hh CR LF Field number Description 1 2 3 4 5 6 7 hh Track made good in degrees true Track made good in degrees magnetic Speed over the ground SOG in knots Speed over the ground SOG in kilometer per hour Mode Indicator A Autonomous Mode D Differential Mode E Estimated dead reckoning Mode M Manual Input Mode S Simulated Mode N Data Not Valid Checksum ZDA Time amp Date The ZDA message contains UTC time the day the month the year and the local time zone SGPZDA hhmmss ss xx xx xxxx hh CR LF Field number Description Anu PWN UTC Day 01 to 31 Month 01 to 12 Year Unused Unused Checksum 90 Resolution T GPS Embedded Board User Guide NMEA 0183 Protocol B Note Fields 5 and 6 are null fields in the Resolution T output A GPS receiver cannot independently identify the local time zone offsets N CAUTION If UTC offset is not available time output will be in GPS time until the UTC offset value is collected from the GPS satellites When the offset becomes available the time will jump to UTC time Note GPS time can be used as a timetag for the 1PPS The ZDA message comes out 100 500 msec after the PPS Exception behavior When no position fix is available some ofthe data fields in the NMEA messages will be blank A blank field has no characters between the commas Interruption of GPS
43. Packet 0x32 Accurate Initial Position Latitude Longitude Altitude 51 Command Packet 0x34 Satellite Select For One Satellite Mode 51 Command Packet 0x35 Set or Request I O Options lees 51 Command Packet 0x37 Request Status and Values of Last Position 53 Command Packet 0x38 Request Satellite System Data llle 53 Command Packet 0x39 Set or Request SV Disable and Health Use 53 Command Packet 0x3A Request last raw Measurement llle 54 Command Packet 0x3C Request Current Satellite Tracking Status 54 Command Packet 0x7A Set or Request NMEA Interval and Message Mask 54 Report Packet 0x7B Set NMEA Message Output eee 55 Report Packet 0x42 Single precision Position Fix o o o oooooooo oo 55 Report Packet 0x43 Velocity Fix XYZ ECEF lees 55 Report Packet 0x45 Software Version Information llle 56 Report Packet 0x47 Signal Level for All Satellites Tracked 56 Report Packet 0x4A Single Precision LLA Position Fix llle 57 Report Packet 0x55 I O Options leen 57 Report Packet 0x56 Velocity Fix East North Up ENU 2 0 2 00 ooo oo 58 Report Packet 0x57 Information about Last Computed Fix 59 Report Packet 0x58 GPS System Data Acknowledge from Receiver 59 Report Packet 0x59 Status of Satellite Disable or Ignore Health 62 R
44. RN elevation azimuth and SNR for second satellite 12 13 14 15 PRN elevation azimuth and SNR for third satellite 16 17 18 19 PRN elevation azimuth and SNR for fourth satellite hh Checksum Anu A WU N RMC Recommended Minimum Specific GPS Transit Data The RMC message contains the time date position course and speed data provided by the GPS navigation receiver A checksum is mandatory for this message and the transmission interval may not exceed 2 seconds All data fields must be provided unless the data is temporarily unavailable Null fields may be used when data is temporarily unavailable GPRMC hhmmss ss A 1111 11 a yyyyy yy a X X X X XXXXXX X X a i hh CR LF Field number Description 1 UTC of Position Fix 2 Status A Valid V 2 navigation receiver warning 3 4 Latitude N North or S South 5 6 Longitude E East or W West 7 Speed over the ground SOG in knots Track made good in degrees true Date dd mm yy Magnetic variation in degrees E East W West Resolution T GPS Embedded Board User Guide 89 B NMEA 0183 Protocol Field number Description hh Position System Mode Indicator A Autonomous D Differential E Estimated Dead Reckoning M Manual Input S Simulation Mode N Data Not Valid Checksum Mandatory for RMC VTG Track Made Good and Ground Speed The VTG message conveys the actual track made good COG and the speed relative to the ground S
45. Report Packet 0x8F AC Supplemental Timing Packet This broadcast packet provides supplemental timing information once per second Information regarding position unit status and health and the operational state of the unit is provided This packet cannot be requested When enabled this packet is transmitted once per second shortly after packet 8F AB The position sent in packet 8F AC depends on the Receiver Operating Mode and on self survey activity When a self survey is in progress the position sent is the running average of all of the position fixes collected so far When the self survey ends or whenever the receiver is using a time only operating mode then the position sent is 78 Resolution T GPS Embedded Board User Guide Trimble Standard Interface Protocol A the accurate position the receiver is using to perform time only fixes When the self survey is disabled or otherwise inactive and the receiver is using a position fix operating mode then the position sent is the position fix computed on the last second Data fields Receiver Mode This field shows the fix mode that the GPS receiver is currently configured for The Resolution T spends most of its time in the Overdetermined Clock mode where it uses all available satellites to perform the best time only fix possible See packet BB for a description of all available receiver modes Self Survey Progress When a self survey procedure is in progress this field shows the progress of
46. S accuracy The Resolution T has a clocking rate of 12 504 MHz which enables a steering resolution of 40 ns 20 ns Utilizing both the rising edge and falling edge ofthe pulse will enable a steering resolution of 20ns Using software algorithms like an overdetermined clock solution the Resolution T mitigates the effects of clock error to achieve a PPS accuracy within 15 ns 1 to GPS UTC after survey is complete Resolution T GPS Embedded Board User Guide System Operation 5 Timing operation The Resolution T automatically outputs a PPS and time tag With an accurate reference position the receiver automatically switches to an overdetermined clock mode activates its TRAIM algorithm and outputs a precise PPS Using a simple voting scheme based on pseudo range residuals the Resolution T integrity algorithm automatically removes the worst satellite with the highest residual from the solution set if that satellite s residual is above a certain threshold The Resolution T s default configuration provides optimal timing accuracy The only item under user or host control that can affect the receiver s absolute PPS accuracy is the delay introduced by the antenna cable For long cable runs this delay can be significant 1 25 ns per foot TSIP packet 8Ex4A sets the cable delay parameter which is stored in non volatile memory For the best absolute PPS accuracy adjust the cable delay to match the installed cable length check with your cable m
47. SIP may be characterized as a set of data packets used to transmit information to and receive information from a Trimble GPS receiver Trimble products commonly support a version of TSIP which is customized to the attributes of the product This appendix describes the Resolution T customization MN WARNING The Resolution T GPS receiver is ready to accept TSIP commands approximately 2 1 seconds after power up If a command is sent to the receiver within this 2 1 second window the receiver will ignore the command The Resolution T GPS receiver will not respond to commands sent within the 2 1 second window and will discard any associated command data Note This appendix has been generated and reviewed with care however history has shown that it is surprisingly difficult to generate a TSIP appendix which is entirely free of errors There is no reason to believe that this appendix will be an exception Trimble is always grateful to receive reports of any errors in either products or documentation Resolution T GPS Embedded Board User Guide 40 Trimble Standard Interface Protocol A Introduction TSIP is a powerful and compact interface protocol which has been designed to allow the system developer a great deal of flexibility in interfacing to a Trimble product Many TSIP data packets are common to all products which use TSIP An example would be a single precision position output packet Other packets may be unique to a product Cu
48. Single meters 12 15 clock Bias Single meters always relative to GPS 16 19 time of fix Single seconds The LLA conversion is done according to the datum selected using packet 8E 15 The default is WGS 84 Altitude is referred to the datum or the MSL Geoid depending on which I O LLA altitude option is selected with packet 0x35 The time of fix is in GPS time or UTC depending on which I O timing option is selected CAUTION When converting from radians to degrees significant and readily visible errors will be introduced by use of an insufficiently precise approximation for the constant T pi The value of a constant T as specified in ICDGPS 200 is 3 1415926535898 CAUTION The MSL option is only valid with the WGS 84 datum When using other datums only the HAE option is valid Report Packet 0x55 I O Options This packet provides the current I O option states in response to packet 0x35 request The data format is the same as for packet 0x35 and is repeated below for convenience These abbreviations apply to the following table ALT Altitude ECEF Earth centered Earth fixed XYZ Cartesian coordinates LLA latitude longitude altitude HAE height above ellipsoid WGS 84 Earth model ellipsoid MSL geoid Earth mean sea level mode UTC coordinated universal time Byte Data Type Bit Default Value Meaning Associated Packet 0 UINTS Position 0 0 0 ECEF on 0x42 or 0x83 1 ECEF off 1 1 0 LLA off 0x4A or 0x84 1 LL
49. TS ARE ACQUIRED IN SUCH A CASE PLEASE CONTACT YOUR LOCAL TRIMBLE AUTHORIZED DEALER FOR APPLICABLE WARRANTY INFORMATION Official Language THE OFFICIAL LANGUAGE OF THESE TERMS AND CONDITIONS IS ENGLISH IN THE EVENT OF A CONFLICT BETWEEN ENGLISH AND OTHER LANGUAGE VERSIONS THE ENGLISH LANGUAGE SHALL CONTROL Notice to Our European Union Customers For product recycling instructions and more information please go to www trimble com ev shtml Recycling in Europe To recycle Trimble WEEE Waste Electrical and Electronic Equipment products that run on electrical power Call 31 497 53 24 30 and ask for the WEEE Associate Or mail a request for recycling instructions to Trimble Europe BV c o Menlo Worldwide Logistics Meerheide 45 5521 DZ Eersel NL Safety Information Warnings and Cautions A A An absence of specific alerts does not mean that there are no safety risks involved Always follow the instructions that accompany a Warning or Caution The information they provide is intended to minimize the risk of personal injury and or damage to the equipment In particular observe safety instructions that are presented in the following formats WARNING A Warning alerts you to a likely risk of serious injury to your person and or damage to the equipment CAUTION A Caution alerts you to a possible risk of damage to the equipment and or loss of data Operation and storage A A WARNING
50. UINT8 An 8 bit unsigned number 0 to 255 SINT8 An 8 bit signed number 128 to 127 INT16 A 16 bit unsigned number 0 to 65 535 Resolution T GPS Embedded Board User Guide Trimble Standard Interface Protocol A Data type Description SINT16 A 16 bit signed number 32 768 to 32 767 UINT32 A 32 bit unsigned number 0 to 4 294 967 295 SINT32 A 32 bit signed number 2 147 483 648 to 2 147 483 647 e Single Float 4 bytes 3 4x10 38 to 1 7x1038 24 bit precision e Double Float 8 bytes 1 7x10 308 to 3 4x10308 53 bit precision Note Default settings are 9600 8 odd 1 Packet descriptions Command Packet 0x1C Firmware Version 01 The command packet 0x1C 01 may be issued to obtain the firmware version The product name is Resolution T GPS Timing Receiver The packet format is defined in the following table Byte Item Type Value Meaning 0 Packet ID UINT8 0x1C Packet ID Ox1C 1 Sub code UINT8 0x01 Sub code 0x01 for software component version information request Report Packet 0x1C 81 Byte Item Type Value Meaning 0 Packet ID UINT8 0x1C Packet ID 0x1C 1 Sub code UINT8 0x81 Sub code 0x81 for software component version information report 2 Reserved UINT8 Any Reserved 3 Major version UINT8 Any Firmware major version 4 Minor version UINT8 Any Firmware minor version 5 Build number UINT8 Any Firmware build number 6 Month UINT8 1 12 Firmware build month 7 Day UINT8 1 31 Firmware build d
51. USER GUIDE Resolution T GPS Embedded Board y Po j Trimble Z E The right one USER GUIDE Resolution T GPS Embedded Board Version 2 0 Revision B Part Number 54655 05 ENG August 2009 Trimble Corporate Office Trimble Navigation Limited Component Technologies 935 Stewart Drive Sunnyvale CA 94085 U S A Phone 1 800 767 4822 www trimble com Support Offices Trimble Navigation Limited Component Technologies 935 Stewart Drive Sunnyvale CA 94085 US A Phone 1 800 767 4822 Legal Notices Copyright and Trademarks 2005 2009 Trimble Navigation Limited Trimble the Globe amp Triangle logo and Resolution T are trademarks of Trimble Navigation Limited registered in the United States and in other countries Bullet is a trademark of Trimble Navigation Limited Microsoft and Windows are either registered trademarks or trademarks of Microsoft Corporation in the United States and or other countries All other trademarks are the property of their respective owners Release Notice This is the August 2009 release Revision B of the Resolution T GPS Embedded Board User Guide part number 54655 05 ENG LIMITED WARRANTY TERMS AND CONDITIONS Product Limited Warranty Subject to the following terms and conditions Trimble Navigation Limited Trimble warrants that for a period of one 1 year from date of purchase this Trimble product the Product will substantially conform t
52. UTC GPS timing Ox8F A2 Ox8E A4 test modes Ox8F A4 Ox8E A5 packet broadcast mask Ox8F A5 Ox8E A6 self survey commands Ox8F A6 Ox8E A9 self survey parameters Ox8F A9 Packet structure 46 TSIP packet structure is the same for both commands and reports The packet format is lt DLE gt lt id gt lt data string bytes gt lt DLE gt lt ETX gt Where lt DLE gt is the byte 0x10 lt ETX gt is the byte 0x03 lt id gt is a packet identifier byte which can have any value excepting lt ETX gt and The bytes in the data string can have any value To prevent confusion with lt DLE gt the frame sequences lt DLE gt lt id gt and lt DLE gt lt ETX gt every lt DLE gt byte in the data string is preceded by an extra lt DLE gt byte stuffing These extra lt DLE gt bytes must be added stuffed before sending a packet and removed after receiving the packet Note A simple lt DLE gt lt ETX gt sequence does not necessarily signify the end of the packet as these can be bytes in the middle of a data string The end of a packet is lt ETX gt preceded by an odd number of lt DLE gt bytes Multiple byte numbers integer float and double follow the ANSI IEEE Std 754 IEEE Standard for binary Floating Point Arithmetic They are sent most significant byte first You must switch the byte order on Intel based machines The data types used in the Resolution T TSIP are as follows Data type Description
53. ain that the adaptor has prongs compatible with your outlets AC adaptors are designed for indoor use only Avoid using the AC adaptor in wet outdoor areas Unplug the AC adaptor from power when not in use Do not short the output connector There are no user serviceable parts in this product Should damage to the AC adaptor occur replace it with a new Trimble AC adaptor Resolution T GPS Embedded Board User Guide Contents Safety Information lt o s suck ow ca a A we UR 3 Warnings and Cautions 522 zero aoe bed ee ew eee TER i Pu d ERG 3 Operation and Storage vsa ts oce gp hale e EUR ER ee Pet ei Ye ee ee 3 Routing any Cables 2 iuh oa sa Ra RES Se Oe RU edo bo E RUE RUE RA Ow Ru 3 AC adaptor safety 2 odes acoso bon eb poo eg D dete ok ace ca i e n aha esae d 4 1 INEFOQUCHION MMC ir Side he e e A A a a 9 Opera arial a ROPA mood gui ote QU ded e A da Aa UNA S HZ EINE Ge oa 10 Timing features vaina beseech SON db Pee a be obs edo Seok Foose i4 10 Starter Mb PC m 10 Useand Care sics aoc die oe See ae Haida deed beat a oe OS 10 Technical assistance 2 secs m dones sk ho ox e DP ee a ar ded a a ed 11 NOU COMMENTS sik ia ces elm RA e a a e A a RR 11 2 Setting up the Resolution T Starter Kit 12 System requirements oia ge ale y PS A KA wa aoe ea dd a Ba 13 Hardware e Seach Ra baw ie e RO ta OA anette Aa A 13 Computer eiiiai oe a A PUER A a EE EPA E RUE 13 System
54. anufacturer for the delay for a specific cable type Generally the cable delay is about 1 25 nanoseconds per foot of cable To compensate for the cable delay use a negative offset to advance the PPS output Note GPS time differs from UTC Universal Coordinated Time by a small sub microsecond offset and an integer second offset The small offset is the steering offset between the GPS DoD clock ensemble and the UTC NIST clock ensemble The large offset is the cumulative number of leap seconds since 1 January 1970 which on 31 December 2006 was increased from 14 to 16 seconds Historically the offset increases by one second approximately every 18 months usually just before midnight on 30 June or 31 December System designers should note whether the output time is UTC or GPS time Using Resolution T in mobile applications Although it is intended primarily for use in static applications the Resolution T can also be used in mobile applications The factory default settings for the Resolution T assume that the antenna is going to be used in a static timing application To use the Resolution T in mobile applications you must disable the receiver s self survey mechanism and ensure that a stored position does not exist in the flash ROM To prepare the Resolution T receiver for mobile applications complete the following steps 1 Confirm that there is no stored position in the flash ROM by using command packet 8E A6 to delete the stored pos
55. atellites are not geostationary so satellites in view are constantly changing Each GPS satellite contains four highly stable atomic clocks which are continuously monitored and corrected by the GPS control segment Consequently the GPS constellation can be considered a set of 24 orbiting clocks with worldwide 24 hour coverage A Trimble GPS receiver uses the signals from these GPS clocks to correct its internal clock which is not as stable or accurate as the GPS atomic clocks A GPS receiver like the Resolution T outputs a highly accurate timing pulse PPS generated by its internal clock which is constantly corrected using the GPS clocks In the case of the Resolution T this timing pulse is synchronized to GPS UTC time within 15 nanoseconds 1 after survey is complete In addition to serving as highly accurate stand alone time sources GPS timing receivers are used to synchronize distant clocks in communication or data networks This is possible because all GPS satellites are corrected to a common master clock Therefore the relative clock error is the same regardless of which satellites are used For synchronization applications requiring a common clock GPS is the ideal solution Position and time errors are related by the speed of light This is why an accurate reference position is critical A position error of 100 meters corresponds to a time error of approximately 333 ns The GPS receiver s clocking rate and software affect PP
56. atellites are yet usable In order for a satellite to be usable it must be tracked long enough to obtain ephemeris and health data Bit 5 When 1 indicates that a self survey procedure is in progress Bit6 When I indicates that there is no accurate position stored in flash ROM Bit 7 When I indicates that the GPS system has alerted the Resolution T that a leap second transition is pending Bit 8 When I indicates that the Resolution T is operating in one of its test modes Resolution T GPS Embedded Board User Guide 79 A Trimble Standard Interface Protocol Bit9 When 1 indicates that the accuracy of the position used for time only fixes is questionable This alarm may indicate that the unit has been moved since the unit completed the last self survey If this alarm persists resurvey the position ofthe unit Bit 11 When 1 indicates that the Almanac is not current or complete Bit 12 When 1 indicates that the PPS was not generated this second This could mean that there wasnt enough usable satellites to generate an accurate PPS output It could also mean that the unit is generating an Even Second output see Packet 8E 4E and the unit did not output a PPS on the odd second e GPS Decoding Status This field indicates the decoding status of the GPS receiver e Local Clock Bias This field contains the bias of the local clock Note that this data cannot be used to increase the accuracy of the PPS output
57. ations System architecture CHAPTER This chapter describes the operating characteristics of the Resolution T GPS timing receiver including start up satellite acquisition operating modes serial data communication and the timing pulse The Resolution T GPS timing receiver acquires satellites and computes position and time solutions It outputs data in the TSIP or NMEA protocol through its serial port Resolution T GPS Embedded Board User Guide 31 5 System Operation Operation Start up When the Resolution T is turned on it automatically begins to acquire and track GPS satellite signals It obtains its first fix in under one minute During the satellite acquisition process the Resolution T GPS outputs periodic TSIP status messages These status messages confirm that the receiver is working Automatic operation When the Resolution T has acquired and locked onto a set of satellites that pass the mask criteria listed below and has obtained a valid ephemeris for each satellite it performs a self survey After a number of position fixes configurable the self survey is complete At that time the Resolution T automatically switches to a time only mode Satellite masks The Resolution T continuously tracks and uses up to twelve satellites in an overdetermined clock solution The satellites must pass the mask criteria to be included in the solution The following table lists the default satellite masks used by the Resoluti
58. ay 8 9 Year INT16 Any Firmware build year 10 Length of first UINT8 Any The length of the product module name name L1 11 10 L1 Product name UINT8 String Product name in ASCII Resolution T GPS Embedded Board User Guide 47 A Trimble Standard Interface Protocol Command Packet 0x1C 03 hardware component version information The command packet Ox1C 03 may be issued to obtain the hardware component version information The report packet is of variable length depending on the length of the hardware ID The serial number build date fields and the hardware ID are programmed into the Resolution SMT at production The hardware code for the Resolution T GPS Timing Receiver is 3002 ID for Resolution T receiver is Resolution T GPS Timing Receiver The packet format is defined in the following table Byte Item Type Value Meaning 0 Packet ID ULINT8 Ox1C Packet ID Ox1C 1 Sub code UINT8 0x03 Sub code 0x03 for hardware component version information request Report Packet 0x1C 83 hardware component version information Byte Item Type Value Meaning 0 Packet ID UINT8 0x1C Packet ID 0x1C 1 Sub code UINT8 0x83 Sub code 0x83 for hardware component version information report 205 Serial number UINT32 Any Board serial number 6 Build day UINT8 1 31 Day of the board s build date 7 Build month UINT8 1 12 Month of the board s build date 8 9 Build year INT16 Any Year of the board s build date 10 Build
59. bedded Board User Guide 25 3 Hardware Integration e A33 VDC or 5 0 VDC Bullet III rooftop antenna Acompact magnetic mount antenna The antenna receives the GPS satellite signals and passes them to the receiver The GPS signals are spread spectrum signals in the 1575 MHz range and do not penetrate conductive or opaque surfaces Therefore the antenna must be located outdoors with a clear view of the sky The Resolution T GPS receiver requires an active antenna The received GPS signals are very low power approximately 130 dBm at the surface of the earth Trimbles active antenna includes a preamplifier that filters and amplifies the GPS signals before delivery to the receiver 26 Resolution T GPS Embedded Board User Guide CHAPTER Software Interface In this chapter This chapter describes the software interface and describes both communication with the receiver m Start up port protocol and data output options Wm Communicating with the receiver W Port protocol and data output options Resolution T GPS Embedded Board User Guide 27 4 Software Interface Start up The Resolution T GPS timing receiver is a complete 12 channel parallel tracking GPS timing receiver designed to operate with the L1 frequency standard position service Coarse Acquisition code When connected to an external GPS antenna the receiver contains all the circuitry necessary to automatically acquire GPS satellite signal
60. cture The NMEA 0183 protocol covers a broad array of navigation data This broad array of information is separated into discrete messages which convey a specific set of information The entire protocol encompasses over 50 messages but only a sub set of these messages apply to a GPS receiver like the Resolution T The NMEA message structure is described below SIDMSG D1 D2 D3 D4 Dn CS CR LF Where Signifies the start of a message ID The talker identification is a two letter mnemonic which describes the source of the navigation information The GP identification signifies a GPS source MSG The message identification is a three letter mnemonic which describes the message content and the number and order of the data fields F Commas serve as delimiters for the data fields Dn Each message contains multiple data fields Dn which are delimited by commas The asterisk serves as a checksum delimiter cs The checksum field contains two ASCII characters which indicate the hexadecimal value of the checksum CR LF The carriage return CR and line feed LF combination terminate the message NMEA 0183 messages vary in length but each message is limited to 79 characters or less This length limitation excludes the and the CR LF The data field block including delimiters is limited to 74 characters or less Field definitions Many of the NMEA date fields are of variable length and the user should always use
61. e UINT16 39 40 DN UINT16 41 42 At sr SINT16 Ephemeris data type 5 Byte Item Type Meaning 4 SV number UINT8 SV PRN number 5 8 t ephem Single time of collection seconds 9 10 week number UINT16 GPS week number 0 thru 1023 11 retired 12 retired 13 SV accuracy raw UINT8 URA index of SV 0 thru 15 14 SV health UINT8 6 bit health code 15 16 IODC UINT16 Issue of data clock 17 20 tap Single L1 L2 correction term 21 24 toc Single Sec 20 4 3 5 25 28 ap Single Sec 2 4 3 6 29 32 an Single 33 36 afo Single 37 40 SV accuracy Single URA of SV 41 IODE UINT8 issue of data emphemeris Resolution T GPS Embedded Board User Guide 61 A Trimble Standard Interface Protocol 62 Byte Item Type Meaning 42 retired 43 46 Cs Single 47 50 An Single 51 58 Mo Double 59 62 Cu Single 63 70 e Double 71 74 CUS Single 75 82 sqrt A Double 83 86 toe Single Table 2 5 87 90 Cic Single 91 98 OMEGA Double 99 102 Cis Single 103 110 lo Double 111 114 CG Single 115 122 OMEGA Double 123 126 OMEGADOT Single 127 130 IDOT Single 131 138 Axis Double 139 146 n Double 147 154 r1me2 Double sqrt 1 0 e gt 155 162 OMEGA_n Double derived from OMEGA_0 OMEGADOT 163 170 ODOT_n Double derived from OMEGADOT Note All angles are in radians Reference numbers refer to Global Positioning System Standard Positioning Service Signal Specification As of this writing it is available in Adobe Acrobat format at http www navce
62. ed this packet will begin transmission within 20 ms after the PPS pulse to which it refers Data fields Time of Week This field represents the number of seconds since Sunday at 00 00 00 GPS time for the current GPS week Time of week is often abbreviated as TOW Week Number This field represents the current GPS week number GPS week number 0 started on January 6 1980 UTC Offset This field represents the current integer leap second offset between GPS and UTC according to the relationship Time UTC Time GPS UTC Offset The UTC offset information is reported to Resolution T by the GPS system and can take up to 12 5 minutes to obtain Before the Resolution T has received UTC information from the GPS system it is only capable of representing time in the GPS time scale and the UTC offset will be shown as 0 Timing Flags This field is bitwise encoded to provide information about the timing outputs Unused bits are should be ignored Bit 0 When 0 the date and time fields broadcast in packet 8F AB are in the GPS time scale When 1 these fields are in the UTC time scale and are adjusted for leap seconds Use command packet 8E A2 to select either GPS or UTC time scales Bit 1 When 0 the PPS output is aligned to GPS When 1 the PPS output is aligned to UTC Use command packet 8E A2 to select either GPS or UTC PPS alignment Bit 2 When 0 time has been set from GPS When 1 time has net yet been set from GPS Bit 3
63. elds contain the user UTC parameters that are to be used while in test mode 1 A0 This field is the fractional second offset of GPS from UTC at the reference time in seconds A 1 This field is the rate of change of fractional second offset of GPS from UTC in seconds second delta t LS Current integer leap seconds t ot This field is the reference time of week for the A 0 A 1 parameters WN_t This field is the reference week number for the A_0 A_1 parameters WN_LSF This field is the week number of a future leap second event DN This field is the day number of a future leap second event delta_t_LSF This field is the integer number of future leap seconds Test Mode 3 Data Format Byte Item Type Description 0 Subcode UINT8 0xA4 1 Test Mode UINT8 3 Send user UTC parameter 2 5 A_0 Single Seconds 6 9 A 1 Single Seconds second 10 11 delta t LS SINT16 Seconds 12 15 t ot UINT32 Seconds 16 17 WNt UINT16 Week number 18 19 WN_LSF UINT16 Week number 20 21 DN UINT16 Day number 1 7 22 23 delta_t_LSF SINT16 Seconds Command Packet 0x8E A5 Packet Broadcast Mask Use command packet 8E A5 to set the packet broadcast masks or to request the current mask settings The Resolution T replies to requests with response packet 8F A5 The broadcast mask is bitwise encoded to allow the user to turn on and off the broadcast of certain packets For those broadcast packets that have multiple format the Resolution T will broadcast only one of the formats
64. eport Packet 0x5A Raw Data Measurement Data 0 o 63 Report Packet 0x5C Satellite Tracking Status 2 0 llle 63 Report Packet 0x6D All in View Satellite Selection o o oo ooooooo 64 Report Packet 0x83 Double Precision XYZ 1 1 llle 65 Report Packet 0x84 Double Precision LLA Position Fix and Bias Information 65 Command Packet OxBB Set Primary Configuration llle 66 Command Packet OxBC Set Port Configuration leen 67 TSIP Superpackets ouo gena ie ed Poy Gib ecd D Rh D oa 68 Command Packet 0x8E 01 Configure Raw GPS Data Output 68 Command Packet 0x8E 15 Request Current Datum Values 69 Command Packet 0x8E 26 Write Receiver Configuration to Flash ROM 69 Command Packet 0x8E 41 Request Manufacturing Parameters 69 Command Packet Ox8E 42 Stored Production Parameters sls 69 Command Packet 0x8E 4A Set PPS Characteristics o o o oooooo ooo 69 Command Packet 0x8E 4E Set PPS output option o o o o ooooooo ooo 70 Command Packet 0x8E A2 UTC GPS Timing leen 70 Command Packet 0x8E A4 Test Modes llle 71 Command Packet 0x8E A5 Packet Broadcast Mask llle 72 Resolution T GPS Embedded Board User Guide 7 Contents C Command Packet 0x8E A6 Self Survey Command llle 73 Command Packet 0x8E A9 Self Survey Parameters 00000 eee 73 Report Packet
65. erformance and ease of integration are desired The receiver features Trimble s improved signal processing code a high gain RF section for compatibility with standard active gain GPS antennas and a CMOS level pulse per second PPS output for timing and synchronization applications Timing applications are assumed to be static The special timing software used with the Resolution T receiver configures the unit into an automatic self survey mode at start up The receiver will average position fixes for a specified time one per second and at the end of this period will save this reference location At this time the receiver will go into an Overdetermined Clock mode and no longer solve for position but only for clock error and clock bias using all of the available satellites This provides an accuracy of less than 15ns 1 Sigma for the 1PPS output User settings such as port parameters and NMEA settings can be stored in the receiver s non volatile flash memory These settings are retained without main power The Resolution T receiver has a single configurable serial I O communication port Note When customizing port assignments or characteristics confirm that your changes do not affect your ability to communicate with the receiver Resolution T GPS Embedded Board User Guide Setting up the Resolution T Starter Kit 2 Interface protocols The Resolution T receiver operates using one of two protocols protocol selection and port character
66. he AC DC power converter output cable is terminated with a 3 pin connector compatible with the power connector on the metal enclosure The AC power cable is not provided in the kit since this cable can be country specific The input connector is a standard 3 prong connector used on many desktop PCs 18 Resolution T GPS Embedded Board User Guide Setting up the Resolution T Starter Kit 2 Setting up the starter kit Note You can either set up the starter kit temporarily for testing or evaluation purposes or embed it permanently into your system The procedure is largely the same 1 6 T Start up your office computer that is running a suitable Windows operating system and service pack see page 13 and that has a free USB port Download the required software from www trimble com support shtml Select and then save all the relevant files to a directory on the hard drive To use the Monitor software tool to communicated with the GPS receiver you must install the FTDI driver on your computer The starter kit uses a USB 2 0 dual serial port emulator interface chip from Future Technology Devices International Ltd FTDI To do this click the CDM_ Setup exe file that you downloaded earlier If the installation is successful a message FTDI CDM Drivers have been successfully installed appears Click OK Connect one end of the USB cable supplied to the USB connector on the interface unit Connec
67. he Resolution T is a software GPS timing receiver It is a complete all in view 12 channel parallel tracking GPS receiver designed to operate with the L1 frequency standard position service Coarse Acquisition code The Resolution T receives the amplified GPS satellite signals through the antenna feed line connector and passes them to the RF down converter A highly stable crystal reference oscillator operating at 12 504 MHz is used by the down converter to produce the signals used by the DSP The DSP tracks the GPS satellite signals and extracts the carrier code information as well as the navigation data at 50 bits per second Operation of the tracking channels is controlled by the navigation processor The software tracking channels are used to track the highest twelve satellites above the horizon The navigation processor will then use the optimum satellite combination to compute a position The navigation processor also manages the ephemeris and almanac data for all of the satellites and performs the data I O Resolution T GPS Embedded Board User Guide 39 APPENDIX Trimble Standard Interface Protocol In this appendix Introduction Customizing operations parameters Packets output at startup Report packets Resolution T to User Command Packets User to Resolution T Packet structure Packet descriptions TSIP Superpackets Unused or miscellaneous packets Legacy packets unused The Trimble Standard Interface Protocol T
68. he packet with no data bytes or set the Resolution T PPS characteristics The Resolution T responds to a query or set command with packet 8F 4A Byte Item Type Value Meaning 0 Subcode UINT8 0x4A 1 PPS driver switch UINT8 0 off 1 on 2 reserved UINT8 3 PPS polarity UINT8 0 positive 1 negative 4 11 PPS offset or cable delay Double seconds see note 12 15 Bias uncertainty Single meters threshold Resolution T GPS Embedded Board User Guide 69 A Trimble Standard Interface Protocol 70 Note Negative offset values advance the PPS and are normally used to compensate for cable delay Command Packet Ox8E 4E Set PPS output option This command packet sets the PPS driver switch to one of the values listed in Table A 52 The current driver switch value can be requested by sending the packet with no data bytes except the subcode byte Driver switch values 3 and 4 only make sense in Overdetermined Timing mode In any position fix mode the effective choices are always on or during fixes which you get if you set the driver switch to 3 or 4 The Resolution T can also be configured to generate an Even Second pulse in place of the PPS pulse by setting the value as shown in the table below Byte Item Type Value Meaning 0 Subcode UINT8 Ox4E 1 PPS driver switch UINT8 2 PPS is always on PPS is generated every second 3 PPS is output when at least one satellite is tracking PPS is generated every second 4 PPS is output when at
69. hest accuracy fix mode is 3 D manual where altitude is always calculated along with the latitude longitude and time Obtaining a position requires four satellites with a PDOP below the PDOP mask Depending on how the PDOP mask is set 3 D mode can be restrictive when the receiver is subjected to frequent obscuration or when the geometry is poor due to an incomplete constellation Overdetermined Clock mode Overdetermined Clock Mode is used only in stationary timing applications This is the default mode for the Resolution T once a surveyed or user input position is determined After the receiver self surveys its static reference position it automatically Resolution T GPS Embedded Board User Guide 33 5 System Operation switches to Overdetermined Clock Mode and determines the clock solution The timing solution is qualified by a TRAIM algorithm which automatically detects and rejects faulty satellites from the solution In this mode the Resolution T does not navigate or update positions and velocities but maintains the PPS output solving only for the receiver clock error bias and error rate bias rate PPS quantization error 34 The Resolution T uses a high precision fixed frequency oscillator as the timing source to down convert and decode the GPS signal and to generate the PPS output signal Since a fixed frequency oscillator is used the Resolution T must place the PPS output on the clock edge that it determines is close
70. iguration as shipped from the factory the Resolution T outputs only TSIP messages Typically NMEA messages are output at a 1 second interval with the GP talker ID and checksums These messages are output at all times during operation with or without a fix If a different set of messages has been selected using Packet 0x7A and this setting has been stored in flash memory using Packet 0x8E 26 the default messages are permanently replaced until the receiver is returned to the factory default settings Resolution T GPS Embedded Board User Guide NMEA 0183 Protocol B Note The user can configure a custom mix of the messages listed in the table below See Chapter 3 and TSIP command packets OxBC 0x7A and 8E 26 in Appendix A for details on configuring NMEA output N WARNING If too many messages are specified for output you may need to increase the unit s baud rate Message Description GGA GPS fix data GLL Geographic position Latitude Longitude GSA GPS DOP and active satellites GSV GPS satellites in view RMC Recommended minimum specific GPS Transit data VTG Track made good and ground speed ZDA Time and date NMEA 0183 message formats GGA GPS Fix Data The GGA message includes time position and fix related data for the GPS receiver SGPGGA hhmmss ss llll lll a nnnnn nnn b t uu V V W W M x x M y y Zzzz hh lt CR gt lt LF gt Field number Description 1 UTC of Position 2 3 Latitude N North or S S
71. ing fixes The GPS receiver returns the position velocity auto packets specified in the 0x35 message as well as message 0x57 This packet contains no data Command Packet 0x38 Request Satellite System Data This packet requests current satellite data The GPS receiver returns packet 0x58 Byte Item Type Value Meaning 0 Operation UINT8 1 Type of data UINT8 Must always be 1 1 2 Almanac 3 Health page toa WNa 4 lonosphere 5 UTC 6 Ephemeris 2 Sat PRN UINT8 0 Data not satellite ID specific 1 32 Satellite PRN number Command Packet 0x39 Set or Request SV Disable and Health Use A CAUTION Improperly ignoring health can cause the GPS receiver software to lock up as an unhealthy satellite may contain defective data Use extreme caution in ignoring satellite health Normally the GPS receiver selects only healthy satellites based on transmitted values in the ephemeris and almanac which satisfy all mask values This packet allows overriding the internal logic and forces the receiver to either unconditionally disable a particular satellite or to ignore a bad health flag The GPS receiver returns packet 0x59 if operation 3 or 6 is requested otherwise there is no reply It should be noted that when viewing the satellite disables list the satellites are not numbered but are in numerical order The disabled satellites are signified by a 1 and enabled satellites are signified by a 0 Byte Item Type Value Mea
72. istics are user configurable Note The factory default setting for the I O port is TSIP bidirectional e TSIP Trimble Standard Interface Protocol is a powerful binary packet protocol that allows the system designer maximum configuration control over the GPS receiver for optimum performance in timing applications TSIP supports multiple commands and their associated response packets for use in configuring the Resolution T receiver to meet user requirements e NMEA 0183 National Marine Electronics Association is an industry standard protocol common to marine applications NMEA provides direct compatibility with other NMEA capable devices such as chart plotters radar etc The Resolution T receiver supports the ZDA NMEA message for GPS timing You can select other NMEA messages and output rates as required Resolution T starter kit The Resolution T GPS receiver is available in a Starter Kit or as an individual receiver and associated antenna The Starter Kit includes all the components necessary to quickly test and integrate the receiver Resolution T GPS Embedded Board User Guide 15 2 16 Setting up the Resolution T Starter Kit The starter kit includes the Resolution T timing module mounted on an interface motherboard in a durable metal enclosure The motherboard accepts 9 32 VDC power and provides regulated 3 3 V power to the Resolution T receiver The motherboard also contains Two antenna options Bulle
73. ition if one exists 2 Disable the self survey mechanism using command packet 8E A9 If not disabled the self survey mechanism will automatically survey the antennas position and then set the receiver to operate in a static time only mode 3 Set the desired position fix mode using command packet BB 4 Optionally use packet 8E A5 to enable the automatic output packets such as position and velocity Resolution T GPS Embedded Board User Guide 37 5 System Operation 5 Use packet 8E 26 to save this new configuration to Flash storage and to retain these settings during power cycles and resets After these steps are completed the Resolution T receiver is ready to operate properly in mobile applications While operating in a mobile application the receiver can continue to output a PPS pulse as well as timing packets Note The accuracy of the PPS output pulse will be degraded by a factor of about 3 when the unit is operated in a mobile application Customizing operations 38 The Resolution T receiver provides a number of user configurable parameters that allow you to customize the operation of the unit These parameters are stored in flash ROM chip to be retained during loss of power and through resets At reset or power up the receiver configures itself based on the parameters stored in the flash ROM You can change the values of these parameters to achieve the desired operations using a variety of TSIP packets The Resoluti
74. le for use with the Resolution T GPS receiver Digital 10 Power connector pin out The Digital IO Power connector pin out information is provided in the following table PinNumber Function Description 1 Antenna Power Input 3 0VDC to 5 5VDC 55mA max 2 Prime Power Input 3 3VDC 0 3VDC 3 TXDA Port A transmit CMOS 4 Reserved Reserved 5 RXDA Port A receive CMOS 6 1 PPS One Pulse Per Second CMOS 7 No Connect Not used 8 GND Ground Power and Signal Power requirements 24 The Resolution T GPS receiver requires 3 3 VDC 0 3 VDC at 110 mA typical excluding the antenna The on board capacitance is approximately 65 pF An important design consideration for power is the receiver s internal clock frequency at 12 504 MHz 3 KHz Interference spurs on prime power in this narrow frequency band should be kept to less than 1mV The receiver does not require any special power up or down sequencing The receiver power is supplied through pin 2 ofthe I O connector See Table 5 for the power specifications WARNING The Resolution T GPS receiver is ready to accept TSIP commands approximately 2 1 seconds after power up If a command is sent to the receiver within this 2 1 second window the receiver will ignore the command The Resolution T GPS receiver will not respond to commands sent within the 2 1 second window and will discard any associated command data Signal Voltage Current J4 Pin VCC 3 0 3 6 110 mA 2 Ground 0 8
75. lows Byte Item Type Value Definition 0 Sub code U8 0x01 Packet 0x8E 8F sub code 1 Status U8 0 Request successful or auto send mode 1 Requested SV is not being tracked 2 Requested Subframe not decoded yet 2 SV ID U8 1 32 SVID for which a subframe was requested and or decoded 3 Subframe ID U8 1 5 Subframe ID requested and or decoded 4 Week number U8 0 255 Current 8 bit week number 5 8 Word U32 NOTE 1 Subframe Word 1 TLM 9 12 Word U32 NOTE 1 Subframe Word 2 HOW 13 16 Word U32 NOTE 1 Subframe Word 3 17 20 Word 4 U32 NOTE 1 Subframe Word 4 21 24 Word 5 U32 NOTE 1 Subframe Word 5 25 28 Word 6 U32 NOTE 1 Subframe Word 6 29 32 Word 7 U32 NOTE 1 Subframe Word 7 33 36 Word 8 U32 NOTE 1 Subframe Word 8 37 40 Word 9 U32 NOTE 1 Subframe Word 9 41 44 Word 10 U32 NOTE 1 Subframe Word 10 Resolution T GPS Embedded Board User Guide Trimble Standard Interface Protocol A Note Each 32 bit word of the subframe has the following bit format bit number 31 87 2 data parity 0 MSB of data MSB of parity Where Bits 0 1 unused bits 0 s Bits 2 7 parity bits most significant parity bit is at Bit 7 Bits 8 31 data bits most significant data bit is at Bit 31 Report Packet 0x8F 15 Current Datum Values This packet contains 43 data bytes with the values for the datum currently in use and is sent in response to packet 8E 15 If a built in datum is being used both the datum index and the five double
76. m
77. mat Byte Item Type Value Meaning Default 0 Subcode UINT8 OxFF Primary receiver configuration block 1 receiver mode UINT8 0 automatic 4 3D 1 single satellite 1 SV 3 Horizontal 2D 4 Full position 3D 5 DGPS reference 6 2D clock hold 7 Over Determined Clock 2 reserved UINT8 OxFF do not alter 3 Dynamics Code UINT8 1 Land Land 2 Sea 3 Air 4 Stationary 4 reserved UINT8 OxFF do not alter 5 8 Elevation Mask Single 0 2 Lowest satellite elevation for fixes 10 degrees radians 9 12 AMU Mask Single Minimum signal level for fixes 4 13 16 PDOP Mask Single Maximum DOP for fixes 12 17 20 PDOP Switch Single Switches 2D 3D mode 6 21 reserved UINT8 OxFF do not alter 22 Foliage Mode UINT8 0 Never Sometimes 1 Sometimes 2 Always 23 reserved UINT8 OxFF do not alter 24 reserved UINT8 OxFF do not alter 25 reserved UINT8 OxFF do not alter 26 reserved UINT8 OxFF do not alter 27 39 reserved UINT8 OxFF do not alter 66 Resolution T GPS Embedded Board User Guide Trimble Standard Interface Protocol A N CAUTION The operation of the Resolution T can be affected adversely if incorrect data is entered in the fields associated with packet OxBB Know what you are doing Note When sending packet OxBB fields that are specified as do not alter or if you do not want to alter a specific field send a value of OxFF for UINTS types and a value of 1 0 for floating point types The Resolution T will ignore these values Command Packet OxBC Set Port
78. mation Since it is a well established industry standard NMEA 0183 has also gained popularity for use in applications other than marine electronics The latest release of NMEA 0183 is Version 3 0 July 1 2000 Trimble Navigation supports both version 2 1 and version 3 0 The primary change in release 3 0 is the addition of the mode indicators in the GLL RMC and VTG messages For those applications requiring output only from the GPS receiver NMEA 0183 is a popular choice since in many cases an NMEA 0183 software application code already exists The Resolution T is available with firmware that supports a subset of the NMEA 0183 messages GGA GLL GSA GSV RMC VTC and ZDA For a nominal fee Trimble can offer custom firmware with a different selection of messages to meet your application requirements For a complete copy of the NMEA 0183 standard contact NMEA National Office Seven Riggs Avenue Severna Park MD 21146 Phone 1 410 975 9425 or 800 808 6632 NMEA Fax 1 410 975 9450 NMEA 0183 communication interface 84 NMEA 0183 allows a single source talker to transmit serial data over a single twisted wire pair to one or more receivers listeners The table below lists the standard characteristics of the NMEA 0183 data transmissions Signal NMEA standard Baud rate 4800 Data bits 8 Parity None Disabled Stop bits 1 Resolution T GPS Embedded Board User Guide NMEA 0183 Protocol B NMEA 0183 message stru
79. mpted i e above the elevation mask and healthy according to the almanac The receiver sends this packet only in response to packet 0x27 The data format is shown below Up to 12 satellite number signal level pairs may be sent indicated by the count field Signallevelis normally positive If it is zero then that satellite has not yet been acquired If it is negative then that satellite is not currently in lock The absolute value of signal level field is the last known signal level of that satellite Byte Item Type 0 count UINT8 1 satellite number 1 UINT8 2 5 signal level 1 Single 6 satellite number 2 UINT8 7 10 signal level 2 Single etc etc etc Note The signal level provided in this packet is a linear measure of the signal strength after correlation or de spreading Units either AMU or dB Hz are controlled by packet 0x35 56 Resolution T GPS Embedded Board User Guide Trimble Standard Interface Protocol A Report Packet 0x4A Single Precision LLA Position Fix The packet provides current GPS position fix in LLA latitude longitude and altitude coordinates If the I O position option is set to LLA and the I O precision of position output is set to single precision then the receiver sends this packet each time a fix is computed The data format is shown below Byte Item Type Units 0 3 latitude Single radians for north for south 4 7 longitude Single radians for east for west 8 11 altitude
80. n of this information Report Packet 0x84 Double Precision LLA Position Fix and Bias Information This packet provides current GPS position fix in LLA coordinates If the I O position option is set to LLA and the double position option is selected see packet 0x35 the receiver sends this packet each time a fix is computed Byte Item Type Units 0 7 latitude Double radians for north for south 8 15 longitude Double radians for east for west 16 23 altitude Double meters 24 31 clock bias Double meters always relative to GPS 32 35 time of fix Single seconds Note The time of fix is in GPS time or UTC time as selected by the I O timing option AN CAUTION When converting from radians to degrees significant and readily visible errors will be introduced by use of an insufficiently precise approximation for the constant p PI The value of the constant PI as specified in ICDGPS 200 is 3 1415926535898 Resolution T GPS Embedded Board User Guide 65 A Trimble Standard Interface Protocol Command Packet OxBB Set Primary Configuration In query mode packet OxBB is sent with a single data byte and returns report packet OxBB in the format shown below Data Format Query Only Byte Item Type Value Meaning Default 0 Subcode UINT8 0 Query mode TSIP packet OxBB is used to set GPS Processing options The table below lists the individual fields within the OxBB packet Report Packet 0 x BB Data For
81. n uscg gov pubs gps sigspec Report Packet 0x59 Status of Satellite Disable or Ignore Health This packet is sent in response to command packet 0x39 Byte Item Type 0 Operation 1 to 32 Satellite UINT8 Value 3 UINT8 1 per SV 0 Meaning The remaining bytes tell whether a receiver is allowed to select each satellite The remaining bytes tell whether the receiver heeds or ignores each satellite s health as a criterion for selection Enable satellite selection or heed satellite s health Default value Disable satellite selection or ignore satellite s health Resolution T GPS Embedded Board User Guide Report Packet 0x5A Raw Data Measurement Data Trimble Standard Interface Protocol A Packet Ox5A provides raw GPS measurement data If the packet 0x35 auxiliary option byte bit 1 is set this packet is sent automatically as measurements are taken Byte Item Type Units 0 SV PRN number UINT8 1 4 sample length single milliseconds 5 8 signal level single AMU or dB Hz 9 12 code phase single 1 16th chip 13 16 doppler single Hertz L1 17 24 time of measurement double seconds Note The sample length is the number of milliseconds over which the sample was averaged Note The code phase value is the average delay over the sample interval of the received C A code and is measured with respect to the receivers millisecond timing reference Report Packet 0x5C Satellite Tracking Status The recei
82. nd associated decimal fraction are optional if full resolution is not required Defined Some fields are specified to contain pre defined constants most often alpha characters Such a field is indicated in this standard by the presence of one or more valid characters Excluded from the list of allowable characters are the following that are used to indicated field types within this standard A a c hh hhmmss ss ILI x yyyyy yy Numeric Value Fields Variable X X Variable length integer or floating numeric field Optional leading and trailing zeros The decimal point and associated decimal fraction are optional if full resolution is not required example 73 10 73 1 073 1 73 Fixed HEX hh Fixed length HEX numbers only MSB on the left Information Fields Fixed Alpha aa Fixed length field of upper case or lower case alpha characters Fixed Number xx Fixed length field of numeric characters Note Spaces are only be used in variable text fields Units of measure fields are appropriate characters from the Symbol column unless a specified unit of measure is indicated Fixed length field definitions show the actual number of characters For example a field defined to have a fixed length of 5 HEX characters is represented as hhhhh between delimiters in a sentence definition NMEA 0183 message options 86 The Resolution T can output any or all of the messages listed in the table below In its default conf
83. ning 0 Operation UINT8 1 Enable satellite default 2 Disable satellite 3 Request enable disable status of all 32 satellites 4 Heed health default 5 Ignore health 6 Request heed or ignore health on all 32 satellites Resolution T GPS Embedded Board User Guide 53 A Trimble Standard Interface Protocol Byte Item Type Value Meaning 1 Satellite UINT8 0 All 32 satellites 1 32 Any one satellite PRN number Note At power on and after a reset the default values are set for all satellites Command Packet 0x3A Request last raw Measurement This packet requests the most recent raw measurement data for one specified satellite The GPS receiver returns packet 0x5A if data is available Byte Item Type Value Meaning 0 Satellite INT8 0 All satellites in current tracking set number 1 32 Specific desired satellite Command Packet 0x3C Request Current Satellite Tracking Status This packet requests the current satellite tracking status The GPS receiver returns packet 0x5C if data is available Byte Item Type Value Meaning 0 Satellite number INT8 amp 0 All satellites in current tracking set 1 32 Specific desired satellites Command Packet 0x7A Set or Request NMEA Interval and Message Mask The NMEA message determines whether or not a given NMEA message will be output If the bit for a message is set the message will be sent every interval seconds To determine the NMEA interval and message mask use
84. nt parameters in the flash Users can also direct the Resolution T to set the parameter values to their factory default with packet Ox1E Note Whenever configuration data is saved to the flash ROM using 0x8E 26 or other packets the Resolution T automatically performs a reset To customize the Resolution T output for your application 1 Set up the Resolution T using TSIP commands until the desired operation is achieved 2 Use command Ox8E 26 to store the settings in nonvolatile memory These settings will control Resolution T operations whenever it is cold started The following tables illustrate how the user configurable data is mapped The Trimble factory defaults are also provided See packet Ox1E Factory default settings Parameter Factory Default Set Request Report Receiver mode 4 Full Position 3D Dynamics code 1 land Elevation mask 0 175 radians 10 degrees Signal level mask 4 AMU BXBE 0xBB HXBB PDOP mask 12 PDOP switch 6 Foliage mode 1 sometimes 42 Resolution T GPS Embedded Board User Guide Trimble Standard Interface Protocol A Packet I O control Parameter Factory Default Set Request Report Packet broadcast mask mask 0 0x05 Ox8E A5 Ox8E A5 Ox8F A5 mask 1 0x00 Packet 0x35 data position byte 0 0x12 velocity byte 1 0x02 0x35 0x35 0x35 timing byte 2 0x00 auxiliary byte 3 0x00 Datum 0 WGS 84 Ox8E 15 Ox8E 15 Ox8F 15 Serial port configuration Parameter Factory Defa
85. o Trimble s publicly available specifications for the Product and that the hardware and any storage media components of the Product will be substantially free from defects in materials and workmanship Product Software Product software whether built into hardware circuitry as firmware provided as a standalone computer software product embedded in flash memory or stored on magnetic or other media is licensed solely for use with or as an integral part of the Product and is not sold If accompanied by a separate end user license agreement EULA use of any such software will be subject to he terms of such end user license agreement including any differing limited warranty terms exclusions and limitations which shall control over the erms and conditions set forth in this limited warranty Software Fixes During the limited warranty period you will be entitled to receive such Fixes o the Product software that Trimble releases and makes commercially available and for which it does not charge separately subject to the procedures for delivery to purchasers of Trimble products generally If you have purchased the Product from an authorized Trimble dealer rather than rom Trimble directly Trimble may at its option forward the software Fix to he Trimble dealer for final distribution to you Minor Updates Major Upgrades new products or substantially new software releases as identified by Trimble are expressly excluded from this update
86. ommand Packets User to Resolution T The table below summarizes the packets that can be input by the user The table includes the input packet ID a short description of each packet and the associated output packet Input ID Packet Description Output ID Ox1C Firmware Hardware versions Ox1C Ox1E Initiate cold reset or factory reset 0x45 Ox1F software version 0x45 0x24 request GPS satellite selection 0x6D 0x25 initiate soft reset amp self test 0x45 0x27 request signal levels 0x47 0x31 set accurate initial position XYZ ECEF 0x32 set accurate initial position lat long Alt 0x34 satellite selection for one satellite mode 0x35 set request I O options 0x55 0x37 status and values of last position and velocity 0x57 and other enabled packets 0x38 load or request satellite system data 0x58 0x39 set request satellite disable or ignore health 0x59 0x3A request last raw measurement Ox5A 0x3C request current satellite tracking status 0x5C Ox7A NMEA Set Request 0x7B NMEA Output Interval Resolution T GPS Embedded Board User Guide 45 A Trimble Standard Interface Protocol Input ID Packet Description Output ID OxBB set receiver configuration OxBB OxBC set port configuration OxBB Ox8E 4E PPS output option Ox8F 4E Ox8E 15 set request current datum Ox8F 15 Ox8E 26 Save configuration Ox8E 41 request manufacturing parameters Ox8F 41 Ox8E 42 request production parameters Ox8F 42 Ox8E 4A set PPS characteristics Ox8F 4A Ox8E A2
87. on T These masks serve as the screening criteria for satellites used in fix computations and ensure that solutions meet a minimum level of accuracy The satellite masks can be adjusted using the TSIP protocol described in Appendix A Trimble Standard Interface Protocol Mask Setting Notes Elevation 10 SV elevation above horizon SNR AMUs 4 Signal strength PDOP 12 Self survey only Elevation mask Satellites below 10 elevation are not used in the solution Generally signals from low elevation satellites are of poorer quality than signals from higher elevation satellites These signals travel farther through the ionospheric and tropospheric layers and undergo distortion due to these atmospheric conditions SNR mask Although the Resolution T is capable of tracking signals with SNRs as low as 2 the default SNR mask is set to 4 to eliminate poor quality signals from the fix computation Low SNR values can result from low elevation satellites partially obscured signals for example dense foliage or multi reflected signals multipath 32 Resolution T GPS Embedded Board User Guide System Operation 5 Multi reflected signals also known as multipath can degrade the position and timing solution Multipath is most commonly found in urban environments with many tall buildings and a preponderance of mirrored glass Multi reflected signals tend to be weak low SNR value since each reflection diminishes the signal Setting the SNR
88. on T configures itself based on the new parameter immediately but the new parameter value is not automatically saved to the flash ROM You must direct the receiver to save the parameters to the flash ROM To change the parameter values stored in flash ROM send packet Ox8E 26 to direct the Resolution T to save the current parameter values to the flash ROM To save or delete the stored position use command packet Ox8E A6 You can also direct the receiver to set the parameter values to their factory default settings and to erase the stored position with packet Ox1E In brief to customize the Resolution T GPS receiver operations for your application e Configure the receiver using TSIP command packets until the desired operation is achieved e Use TSIP packet Ox8E 26 to save the settings in nonvolatile memory flash ROM e Ifthe position was not automatically saved during the self survey or if it was manually entered the position can be saved to flash memory using TSIP packet 8E A6 The new settings will control receiver operations whenever it is reset or power cycled Configuration parameters The following tables list the user configurable parameters Each table lists the parameter name its factory default value and the TSIP packet that sets or reads the parameter value typically one TSIP packet sets or reads several related parameters Resolution T GPS Embedded Board User Guide System Operation 5 System architecture T
89. or as reported by the Resolution T in packet Ox8FAC The bottom plot is the result of subtracting the quantization error from the PPS offset Resolution T Raw PPS Output T T T T T T I lu I I i 1 I PESE ng er Reet A ee at ee I i I I I I i I lu I msc scs l I I rons tte le are gn o eee lr gt a m d ooo i i NEA en ee eee 1 po l l a el a m p sm a eS d A ee A ates c E A TIEN I I I fis aie alge a So o it d A H ee E PA E ree X J 1 L 1 1 L o e o o o o o e mL UN SS o0 ow CN su 195440 80 90 100 70 40 50 60 Time seconds 20 30 10 Resolution T Quantization Error su 135440 l ak me ae hae se Si ie Nice es ae x der de o A di A ae l i fe Duc odo ees d O aa EDD A a NER gt 1 D ne ee E l l Y A X X I fr tS dp ev Los d v t eee A A ee w J l 1 20 30 40 80 90 100 60 70 20 30 40 50 10 Time seconds Resolution T Raw PPS Output j E me l l t p
90. ort Packet 0x8F 4A Set PPS Characteristics This is sent in response to a query by packet Ox8E 4A See the corresponding command packet for information about the data format Report Packet 0x8F 4E PPS Output This report packet is output after the command packet 8E 4E has been executed See the corresponding command packet for information about the data format Report Packet 0x8F A2 UTC GPS Timing This packet is sent in response to command packet Ox8E A2 See the corresponding command packet for information about the data format Report Packet 0x8F A5 Packet Broadcast Mask This packet is sent in response to Ox8E A5 command and describes which packets are currently automatically broadcast A 0 in a bit field turns off broadcast and a 1 in a bit field enables broadcast See the corresponding command packet for information about the data format Resolution T GPS Embedded Board User Guide Trimble Standard Interface Protocol A Report Packet 0x8F A9 Self Survey Parameters Packet Ox8F A9 is sent in response to command packet 0x8E A9 and describes the current self survey parameters See the corresponding command packet for information about the data format Report Packet 0x8F AB Primary Timing Packet This broadcast packet provides time information once per second GPS week number GPS time of week TOW UTC integer offset time flags date and time of day TOD information is provided This packet cannot be requested If enabl
91. outh 4 5 Longitude E East or W West 6 GPS Quality Indicator 0 No GPS 1 GPS 2 DGPS 7 Number of Satellites in Use 8 Horizontal Dilution of Precision HDOP 9 10 Antenna Altitude in Meters M Meters 11 12 Geoidal Separation in Meters M Meters Geoidal separation is the difference between the WGS 84 earth ellipsoid and mean sea level 13 Age of Differential GPS Data Time in seconds since the last Type 1 or 9 Update 14 Differential Reference Station ID 0000 to 1023 hh Checksum Resolution T GPS Embedded Board User Guide 87 88 NMEA 0183 Protocol GLL Geographic Position Latitude Longitude The GLL message contains the latitude and longitude of the present vessel position the time of the position fix and the status SGPGLL 1111 111 a yyyyy yyy a hhmmss ss A i hh CR lt LF gt Field number Description 1 2 3 5 6 hh Latitude N North or S South Longitude E East or W West UTC of position Status A Valid V Invalid Mode Indicator Mode A Autonomous Mode D Differential Mode E Estimated dead reckoning Mode M Manual Input Mode S Simulated Mode N Data Not Valid Checksum GSA GPS DOP and Active Satellites The GSA messages indicates the GPS receiver s operating mode and lists the satellites used for navigation and the DOP values of the position solution SGPGSA a X XX XX XX XX XX XX XX XX XX XX XX XX X X X X X X hh CR LF Field number
92. packet contains no data The GPS receiver returns packet 0x6D Resolution T GPS Embedded Board User Guide 49 A Trimble Standard Interface Protocol Command Packet 0x25 Initiate Hot Reset amp Self Test This packet commands the GPS receiver to perform a software hot reset This is not equivalent to cycling the power RAM is not cleared The GPS receiver performs a self test as part of the reset operation This packet contains no data Following completion of the reset the receiver will output the start up messages The GPS receiver sends packet 0x45 on power up reset and on request thus if packet 0x45 appears unrequested then either the GPS receiver power was cycled or the GPS receiver was reset Command Packet 0x27 Request Signal Levels This packet requests signal levels for all satellites currently being tracked This packet contain no data The GPS receiver returns packet 0x47 hex Command Packet 0x31 Accurate Initial Position XYZ Cartesian ECEF This packet provides an accurate initial position to the GPS receiver in XYZ coordinates Either the single precision or the double precision version of this packet may be used however we recommend using the double precision version for greatest accuracy The GPS receiver uses this position for performing time only fixes If a survey is in progress when this command is sent the survey is aborted and this position data is used immediately The Resolution T will automatically switch
93. precision values for that index are returned If the receiver is operating on a custom user entered datum the datum index is set to 1 and the five values are displayed These five values describe an ellipsoid to convert ECEF XYZ coordinate system into LLA Byte Type Value Description 0 Super Packet ID 14 1 2 Datum index 1 for Datum Index custom 3 10 DOUBLE DX meters 11 18 DOUBLE DY meters 19 26 DOUBLE DZ meters 27 34 DOUBLE A axis meters 35 42 DOUBLE Eccentricity squared none Report Packet 0x8F 41 Stored Manufacturing Operating Parameters This packet is sent in response to a command 0x8E 41 Byte Item Type Units 0 Subcode UINT8 0x41 1 2 board serial number prefix SINT16 3 6 Board serial number UINT32 7 Year of build UINT8 8 Month of build UINT8 9 Day of build UINT8 10 Hour of build UINT8 11 14 Oscillator offset Single Resolution T GPS Embedded Board User Guide 75 A Trimble Standard Interface Protocol 76 Byte Item Type Units 15 16 Test code identification number UINT16 Report Packet 0x8F 42 Stored Production Parameters This packet is sent in response to Ox8E 42 Byte Item Type Units 0 Subcode UINT8 0x42 1 Production options prefix UINT8 2 Production number extension UINT8 3 4 Case serial number prefix UINT16 5 8 Case serial number UINT32 9 12 Production number UINT32 13 14 Reserved UINT16 15 16 Machine identification number UINT16 17 18 Reserved UINT16 Rep
94. r end of the cable to the COM port of your computer 2 Download the DSP Monitor program DSPMon exe onto your computer s hard drive 3 Right click in the bottom right of the DSP monitor screen to specify the communications port and protocol When the DSP Monitor screen appears the TX and RX indicators appear in the lower left corner of the status bar A blinking TX indicates that the PC is transmitting commands to the receiver a blinking RX indicates that the PC is Resolution T GPS Embedded Board User Guide Setting up the Resolution T Starter Kit 2 receiving reports from the receiver If either of these indicators stop blinking there is no activity The PC COM port settings appear in the lower right corner of this same status bar 4 Connect a GPS antenna to the receiver to complete the self survey Once the receiver has achieved a position fix the following information appears position time satellites tracked GPS receiver status Notes The receiver also sends a health report every few seconds even if satellites are not being tracked If the DSP Monitor program displays a question mark in a data field the receiver has not reported a status for this field If a remains in the data field the GPS module may not be communicating with the computer Recheck the interface cable connections and verify the serial port selection and settings If the communication failure please call the Trimble Technical Assis
95. s are shown below These options can be set into non volatile memory flash ROM with the Ox8E 26 command The GPS receiver returns packet 0x55 These abbreviations apply to the following table ALT Altitude ECEF Earth centered Earth fixed XYZ Cartesian coordinates LLA latitude longitude altitude HAE height above ellipsoid WGS 84 Earth model ellipsoid MSL geoid Earth mean sea level mode UTC coordinated universal time Byte Data Type Bit Default Value Meaning Associated Packet 0 Position 0 0 0 ECEF off 0x42 or 0x83 1 ECEF on 1 1 0 LLA off 0x4A or 0x84 1 LLA on 2 0 0 HAE datum Ox4A or 0x84 1 MSL geoid Note 1 3 0 0 reserved 4 0 single precision position 0x42 4A 0x83 84 1 double precision position 5 7 0 reserved 1 velocity 0 0 ECEF off 0x43 1 ECEF on 1 1 0 ENU off 0x56 1 ENU on 2 7 0 reserved 2 timing 0 0 GPS time reference 0x42 0x43 0x4A 0x83 1 UTC time reference 0x84 0x56 3 auxiliary 0 0 0 packet 5A off 0x5A 1 packet 5A on 1 0 0 reserved 2 reserved 0 0 output AMU 0x5A 0x5C 0x47 1 output dB Hz 4 7 reserved 0 0 52 Note When using the MSL altitude output the current datum must be set to WGS 84 Resolution T GPS Embedded Board User Guide Trimble Standard Interface Protocol A Command Packet 0x37 Request Status and Values of Last Position This packet requests information regarding the last position fix normally used when the GPS receiver is not automatically outputt
96. s track up to 12 GPS satellites and compute location speed heading and time At power up the receiver will begin a sel survey process Upon completion the receiver will provide an overdetermined timing solution The first time the receiver is powered up itis searching for satellites from a cold start no almanac time ephemeris or stored position While the receiver will begin to compute position solutions within the first 46 seconds the receiver must continuously track satellites for approximately 15 minutes to download a complete almanac and ephemeris This initialization process should not be interrupted The receiver will respond to commands almost immediately after power up see Warning below WARNING The Resolution T GPS receiver is ready to accept TSIP commands approximately 2 1 seconds after power up If a command is sent to the receiver within this 2 1 second window the receiver will ignore the command The Resolution T GPS receiver will not respond to commands sent within the 2 1 second window and will discard any associated command data Communicating with the receiver The Resolution T GPS receiver supports two message protocols TSIP and NMEA Communication with the receiver is through a CMOS compatible serial port The port characteristics can be modified to accommodate your application requirements Port parameters are stored in non volatile memory flash which does not require back up power Table 6 lists the defaul
97. s Association NMEA protocol is an industry standard data protocol which was developed for the marine industry Trimble has chosen to adhere stringently to the NMEA 0183 data specification as published by the NMEA The Resolution T GPS receiver also adheres to the NMEA 0183 Version 3 0 specification NMEA data is output in standard ASCII sentence formats Message identifiers are used to signify what data is contained in each sentence Data fields are separated by commas within the NMEA sentence In the Resolution T GPS receiver NMEA is an output only protocol The receiver is shipped from the factory with the TSIP protocol configured on Port 1 The receiver can be reconfigured using TSIP command packet OxBC in conjunction with TSIPCHAT DSP Monitor or a user written serial interface program The NMEA output messages selection and message output rate can be set using TSIP command packet 0x7A The default setting is to output the ZDA message at a 1 second interval when the receiver output protocol is configured to NMEA using packet OxBC If NMEA is to be permanent for the application the protocol configuration OxBC and NMEA message output setting 0x7A can be stored in the non volatile memory on board flash using TSIP command 0x8E 26 Resolution T GPS Embedded Board User Guide System Operation In this chapter Operation PPS quantization error Data communication Using Resolution T in mobile applications Customizing oper
98. solution T module from the motherboard The Resolution T GPS receiver is secured to the motherboard standoffs with Phillips head screws allowing for removal and integration with the user s application Follow these steps to remove the receiver from the motherboard 1 Disconnect power to the enclosure 2 Remove base plate and unplug the RF cable from the receiver 3 Use a small Phillips screwdriver to remove the securing hardware which holds the Resolution T GPS receiver to the motherboard Resolution T GPS Embedded Board User Guide 13 2 Setting up the Resolution T Starter Kit A 4 Gently rock the board loose from the motherboard I O connector WARNING Before opening the interface unit disconnect the unit from any external power source and confirm that both you and your work surface are properly grounded for ESD protection The Resolution T is designed for embedded applications The digital I O lines and power lines are not designed with additional ESD protection like a stand alone receiver would be Use standard CMOS ESD handling precautions when removing and installing the receiver module Timing receiver performance 14 The Resolution T GPS timing receiver is a complete 12 channel parallel tracking GPS receiver designed to operate with the L1 frequency Standard Position Service Coarse Acquisition code The receiver is designed in a single board format specially adapted for timing applications where reliability p
99. ssociated input packet In some cases the response packets depend on user selected options Output ID Packet Description Input ID Ox1C Firmware Hardware versions Ox1C 0x42 single precision XYZ position 0x37 auto 0x43 velocity fix XYZ ECEF 0x37 auto 0x45 software version information Ox1E Ox1F power up 0x47 signal level for all satellites 0x27 Ox4A single precision LLA position 0x37 auto 0x55 1 0 options 0x35 0x56 velocity fix ENU 0x37 auto 0x57 information about last computed fix 0x37 0x58 GPS system data acknowledge 0x38 0x59 sat enable disable amp health flag 0x39 0x5A raw measurement data 0x3A 0x5C satellite tracking status 0x3C 0x6D all in view satellite selection 0x24 auto 0x83 double precision XYZ 0x37 auto 44 Resolution T GPS Embedded Board User Guide Trimble Standard Interface Protocol A Output ID Packet Description Input ID 0x84 double precision LLA 0x37 auto OxBB primary configuration OxBB OxBC port configuration OxBC Ox8F 15 current datum values Ox8E 15 Ox8F 41 stored manufacturing operating parameters Ox8E 41 0x8F 42 stored production parameters 0x8E 42 Ox8F 4A set PPS characteristics Ox8E 4A Ox8F A2 UTC GPS timing Ox8E A2 Ox8F A4 test modes Ox8E A4 Ox8F 4E PPS output option Ox8E 4E Ox8F A5 packet broadcast mask Ox8E A5 Ox8F A6 Self survey command Ox8E A6 Ox8F A9 Self survey parameters Ox8E A9 Ox8F AB primary timing packet auto Ox8F AC supplemental timing packet auto C
100. st to UTC or GPS This situation results in a quantization error on the placement of the PPS whose magnitude is equal to one half the period of the fixed frequency oscillator The oscillator frequency is 12 504 MHz which is equivalent to a period just under 80 nanoseconds Since both clock edges are used the quantization error on the PPS output is between 20ns The quantization error is illustrated below The top waveform represents the 12 504 MHz clock The Resolution T output must be placed on one of the edges of this clock The middle waveform represents the UTC GPS on time mark as determined by the receiver s electronics The bottom waveform represents the Resolution T PPS output which is output on the clock edge closest to the actual UTC GPS on time mark 12 504 Mhz Clock UTC or GPS PPS P ii AAA The amount of quantization error present on each PPS output pulse is reported in packet Ox8F AC This quantization error information can be used to reduce the effective amount of jitter on the PPS pulse Resolution T PPS The figures below illustrate the result ofremoving the quantization error from the PPS output in a user system The top slot shows the offset of the PPS output pulse relative to a stable standard such as a Cesium atomic clock The quantization error is responsible for the jagged appearance of the waveform The middle plot shows the Resolution T GPS Embedded Board User Guide 5 System Operation quantization err
101. stom packets are only used in the products for which they have been created Interface scope The Resolution T GPS module has one configurable serial I O communication port which is a bi directional control and data port utilizing a Trimble Standard Interface Protocol TSIP The data I O port characteristics and other options are user programmable and stored in non volatile memory flash ROM The TSIP protocol is based on the transmission of packets of information between the user equipment and the GPS receiver Each packet includes an identification code that identifies the meaning and format of the data that follows Each packet begins and ends with control characters Automatic output packets The Resolution T GPS embedded timing board is configured to automatically output the 0x8F AB and 0x8F AC packets For most system implementations these output packets provide all of the information required for operation including time position GPS status and health The following packets can be broadcast if enabled with packet Ox8E A5 and 0x35 By default only packets Ox8F AB and Ox8F AC are enabled for output This table shows the broadcast output packets Broadcast Description Masking Request When Sent Packet ID Packet ID Packet ID 0x42 Position XYZ ECEF single 0x35 0x37 When a position fix is computed precision 0x43 Velocity XYZ single precision 0x35 0x37 When a position fix is computed 0x4A Position LLA single precision 0x35
102. t III GPS antenna 5 V F connector Miniature magnetic mount antenna e 50 feet 20 m RG 59 antenna cable terminated with F connectors F F e Interface cable USB e AC DC power supply adapter Input 100 240 VAC Output 24 VDC e SMB to F adapter cable RG 316 antenna transition cable Software tools used to communicate with the receiver are available for download from www trimble com tmg resolutiont ts asp including the Resolution T GPS Embedded Board User Guide this document and the Monitor Program Note The Resolution T GPS receiver is also available as an individual receiver and associated antenna Starter kit interface unit The starter kit interface unit consists of a Resolution T GPS receiver attached to an interface motherboard housed in a sturdy metal enclosure This packaging simplifies evaluation and software development with the receiver by providing a USB interface which is compatible with most PC communication ports Power 9 32 VDC is supplied through the power connector on the front of the interface unit The motherboard features a switching power supply which converts this voltage input to the 3 3 V required by the receiver and the 5 V required by the antenna The USB connector allows for an easy connection to an office computer using the USB interface cable provided in the starter kit The metal enclosure protects the receiver and the motherboard for testing outside of the laboratory environment The Resolu
103. t port characteristics Software tools The software tools provided on the Trimble website include a user friendly Windows application to facilitate communication with the receiver via the Trimble Standard Interface Protocol TSIP Port configuration The Resolution T GPS receiver has a single I O port The following table shows the default protocol and port configuration for the receiver as delivered from the factory TSIP IN OUT is the default protocol The following table shows the default protocol and port configuration TSIP Input TSIP Output Baud Rate 9600 Data Bits 8 Parity Odd Stop Baud Rate 9600 Data Bits 8 Parity Odd Stop Bits 1 No Flow Control Bits 1 No Flow Control 28 Resolution T GPS Embedded Board User Guide Software Interface 4 The Resolution T GPS receiver can also be configured to output NMEA messages The industry standard port characteristics for NMEA are e Baud Rate 4800 e Data Bits 8 e Parity None e Stop Bits 1 e No Flow Control Any standard serial communications program such as Windows Hyper Terminal or PROCOMM can be used to view the NMEA output messages TSIP is a binary protocol and outputs raw binary serial data that cannot be read when using Windows Terminal or PROCOMM To view the output of the TSIP protocol in text format use the DSP Monitor program N WARNING When using the TSIP protocol to change port assignments or settings confirm that your changes do not affect
104. t the other end of the USB cable to your computer The USB cable will now supply power to the unit Turn on the interface unit The Power LED will light up green Note Two additional power adapters are supplied an international AC DC adapter and an automotive DC DC adapter 8 The FTDI driver automatically assigns two virtual COM ports to the USB port When you need to assign the virtual COM ports they appear on the monitor screen To view the ports select System Properties Device Manager Ports Resolution T GPS Embedded Board User Guide 19 2 Setting up the Resolution T Starter Kit 9 Connect the magnetic mount GPS antenna to the interface unit 10 Place the antenna outside ll Start up the Monitor program and then select one of the USB virtual COM ports Either the TSIP or NMEA data stream is visible on your monitor features including serial port baud rate are product dependent To view the other protocol restart the Monitor program and then select a different USB virtual COM port Setting up the software toolkit 20 The DSP Monitor program is used to monitor GPS performance and to assist system integrators in developing a software interface for the GPS module It runs on the Windows 95 98 2000 XP and Windows Vista platforms To use the Monitor program to monitor the receiver s performance 1 Connect one end of the serial interface cable to Port 1 of the interface unit Connect the othe
105. tance Center TAC at 1 800 767 4822 Resolution T GPS Embedded Board User Guide 21 CHAPTER Hardware Integration In this chapter Resolution T board Connectors Power requirements Serial interface Pulse per second PPS Mounting GPS antenna The Trimble Resolution T GPS timing receiver delivers accurate timing solutions for use in all applications where precision timing is needed The Resolution T GPS timing receiver typically requires 350 mW of power at 3 3 VDC The receiver includes flash memory for field upgrades and for storing the user configuration Resolution T GPS Embedded Board User Guide 22 Hardware Integration 3 Resolution T board Connectors Digital 10 Power connector The Resolution T GPS receiver uses a single 8 pin 2x4 male header connector for both power and data I O The power and I O connector J4 is a surface mount micro terminal strip This connector uses 0 126 inch 3 2 mm high pins on 0 079 inch 2 mm spacing The manufacturer of this connector is Samtec part number TMM104 01 T D SM Mating connectors A surface mount mating connector from those specified by Samtec as compatible to Samtec TMM 104 01 T D SM is recommended RF connector The RF connector mounted on the Resolution T receiver is a right angle SMB Resolution T GPS Embedded Board User Guide 23 3 Hardware Integration Antenna options Trimble offers either a 3 3 VDC or a 5 0 VDC rooftop antenna and cab
106. tes of unparsable packet Legacy packets unused The four packets below will be sent for historical reasons when the Automatic Output Packets are enabled with packet Ox8E A5 but the same information contained in these packets is contained in packets Ox8E AB and Ox8E AC and these old packets should be ignored Report Packet 0x54 Bias and Bias Rate Information contained in super packets 8F AB or 8F AC Report Packet 0x46 Health of Receiver Information contained in super packets 8F AB or 8F AC Report Packet 0x41 GPS Time Information contained in super packets 8F AB or 8F AC Report Packet 0x4B Machine Code ID and Additional Status Information contained in super packets 8F AB or 8F AC 82 Resolution T GPS Embedded Board User Guide APPENDIX NMEA 0183 Protocol In this appendix Introduction NMEA 0183 communication nterface I NMEA 0183 message structure Field definitions NMEA 0183 message options NMEA 0183 message formats Exception behavior This appendix provides a brief overview of the NMEA 0183 protocol and describes both the standard and optional messages offered by the Resolution T Resolution T GPS Embedded Board User Guide 83 NMEA 0183 Protocol Introduction NMEA 0183 is a simple yet comprehensive ASCII protocol which defines both the communication interface and the data format The NMEA 0183 protocol was originally established to allow marine navigation equipment to share infor
107. the values shown below While fixes are being generated the output order is ZDA GGA GLL VTG GSA GSV RMC Byte Bit Item Type Value Meaning 0 Subcode UINT8 0 1 Interval UINT8 1 225 Fix interval in seconds 2 Reserved UINT8 0 3 Reserved UINT8 0 4 0 RMC Bit 0 On 1 Off 5 1 7 Reserved Bit 0 0 GGA Bit 0 On 1 Off 5 1 GGL Bit 0 On 1 Off 5 2 VTG Bit 0 On 1 Off 54 Resolution T GPS Embedded Board User Guide Trimble Standard Interface Protocol A Byte Bit Item Type Value Meaning 5 3 GSV Bit 0 On 1 Off 5 4 GSA Bit 0 On 1 Off 5 5 ZDA Bit 0 On 1 Off 5 6 7 Reserved Bit 0 Report Packet 0x7B Set NMEA Message Output This packet is sent in response to command packet 7A and has the same data format as packet 7A Report Packet 0x42 Single precision Position Fix This packet provides current GPS position fix in XYZ ECEF coordinates If the I O position option is set to XYZ ECEF and the I O Precision of Position output is set to single precision then the GPS receiver sends this packet each time a fix is computed and at start up The data format is shown below Byte Item Type Units 0 3 X Single meters 4 7 Y Single meters 8 11 Z Single meters 12 15 time of fix Single seconds The time of fix is in GPS time or UTC as selected by the I O timing option in command packet 0x35 Packet 0x83 provides a double precision version of this information Report Packet 0x43 Velocity Fix XYZ ECEF This packet
108. tion T GPS receiver installed in the Starter Kit interface unit is a single port receiver A straight in panel mount RF SMB connector supports the GPS antenna connection The center conductor of the SMB connector also supplies 45 5 VDC for the Low Noise Amplifier of the active antenna Note A 3 3 VDC antenna can also be supported on the Resolution T GPS receiver an 8 pin 2x4 2 mm header J4 supports the interface CMOS level the pulse per second PPS signal CMOS level and the input power 43 3 VDC Resolution T GPS Embedded Board User Guide Setting up the Resolution T Starter Kit 2 The following figure shows the receiver in the metal enclosure The interface motherboard includes a 9 to 32 VDC switching power supply which provides regulated 3 3 VDC power to the receiver regulated 5 VDC power to the antenna and contains circuitry which provides a USB interface to a computer The CMOS level PPS is brought directly out to Pin 9 of the USB connector on the front of the interface unit The Starter Kit includes an AC DC converter for powering the module from an AC wall socket The mounting plate is secured to the metal enclosure with four screws The eight pin I O header on the receiver module connects directly to the motherboard The following figure shows the starter kit interface unit Resolution T GPS Embedded Board User Guide 17 2 Setting up the Resolution T Starter Kit Power Pulse
109. ult Set Request Report Input baud rate 7 9600 baud Output baud 7 9600 baud Data bits 8 Parity 1 odd OxBC OxBC OxBC Stop bits 1 Input protocol 2 TSIP Output protocol 2 TSIP Timing outputs Parameter Factory Default Set Request Report PPSenable 1 enabled 0OxBE 4A Ox8E 4A OX8F 4A PPS sense 1 rising edge PPS offset 0 0 seconds Bias Uncertainty Threshold 300 0 meters Ox8E 4A Ox8E 4A Ox8F 4A PPS Output Qualifier 2 always on Ox8E 4E Ox8E 4E Ox8F 4E UTC GPS Date Time 0 GPS Ox8E A2 Ox8E A2 Ox8F A2 UTC GPS PPS Alignment 0 GPS Ox8E A2 Ox8E A2 Ox8F A2 Accurate position Parameter Factory Default Set Request Report Position No stored position 0x31 Ox8bE AC Ox8F AC 0x32 self survey Resolution T GPS Embedded Board User Guide 43 A Trimble Standard Interface Protocol Self survey Self Survey Factory Default Set Request Report Self survey enable 1 enabled Position save flag 1 save Ox8EA9 Ox8E A9 Ox8F A9 Self survey count 2000 fixes Packets output at startup After completing its self diagnostics the Resolution T automatically outputs the following packets The following table shows the packet power up output messages Output ID Description Notes Ox45 Software version Report packets Resolution T to User The table below summarizes the packets output by the Resolution T The table includes the output packet ID a short description of each packet and the a
110. ver sends this packet in response to command packet 0x3C Byte Bit Item Type Value Meaning 0 SV PRN number UINT8 1 32 PRN 1 0 2 slot number bit 000 not used field 1 3 7 channel number bit 0000 channel 1 field 0001 channel 2 0010 channel 3 0011 channel 4 0100 channel 5 0101 channel 6 0110 channel 7 0111 channel 8 1000 channel 9 1001 channel 10 1010 channel 11 1011 channel 12 2 acquisition flag UNIT8 0 never acquired 1 acquired 2 re opened search 3 ephemeris flag UNIT8 0 flag not set gt 0 good ephemeris 4 7 signal level Single AMU or dBHz 8 11 time of last Single secs GPS time of week measurement 1215 Resolution T GPS Embedded Board User Guide 63 A Trimble Standard Interface Protocol Byte Bit Item Type Value Meaning elevation angle single radians 1619 azimuth angle X single radians 20 old UINT8 0 flag not set measurement 20 measurement old flag 21 integer msec UINT8 0 don t know msec flag 1 known from subframe 2 3 verified by bit crossing 4 verified by good fix 22 bad data flag UINT8 0 flag not set 1 bad parity 2 bad ephemeris health 23 data collection UINT8 0 flag not set flag 20 collection in progress Report Packet 0x6D All in View Satellite Selection This packet provides a list of satellites used for position or time only fixes by the GPS receiver The packet also provides the PDOP HDOP and VDOP of that set and provides the current mode automatic or manual 3 D or 2 D overdetermined

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