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1. z A is the Address select command directive and ROM CODE is the ROM code of the device to be selected Once selected all commands will operate on the selected device until another device is selected The Address command is used to select a device on the 1 Wire bus Once a device has been selected subsequent commands can operate on it without the need to select it again The HA5 will remember the ROM code of a selected device and automatically use it when necessary to re address the selected device without the users need to re send the ROM code ROM codes are determined with the S search C conditional search and F family search commands The Address command selects the 1 Wire device that corresponds to the ROM code in the command Devices may also be selected with the F family search S search or C conditional search commands Once selected all commands will operate on the selected device until another device is selected Example Select the DS2406 with a ROM code of 0600000001C8BE12 then read the channel info byte with the D command address a switch AO A4 on Command Response no checksum aA0600000001 C8BE12 lt CR gt 0600000001 C8BE12 lt CR gt aD lt CR gt C7 lt CR gt see D command for details Embedded Data Systems LLC 2019 Fortune Drive Lawrenceburg KY 40342 Phone Fax 502 859 5490 7 33 WRITE READ BIT Command B WRITE READ BIT Form a Bv ch
2. Le ee Embedded Data Systems LLC 2019 Fortune Drive Lawrenceburg KY 40342 Phone Fax 502 859 5490 19 33 CONNECTOR PINOUTS Screw Connector PIN SIGNAL SYMBOL DESCRIPTION PGND G Power Ground 1 Wire Ground Pin C Microlan ground 1 Wire Input Output Pin S Microlan network I O BO PO PW R NA ad Power unreg 5 16 V DC L D i l RJ 11 PINOUT RJ11 PIN SIGNAL DESCRIPTION 1 No connection No connection 2 PGND Power Ground 3 1 Wire Input Output Pin Microlan network I O 4 1 Wire Ground Pin Microlan ground 5 No connection No connection 6 PWR Power unreg 5 16 V DC DB9 PINOUT SIGNAL 9 PIN CONNECTOR RS232 RS485 TTL DB9 Signal DESCRIPTION FUNCTION NC 1 NC No connection TXD 2 Transmit Data TXRX TX output RXD 3 Receive Data TXRX RX input DTR 4 PWRIN1 input power optional RTS 7 PWRIN2 input power optional GND 5 Ground reference NC 6 NC No connection NC 8 NC No connection NC 9 NC No connection Embedded Data Systems LLC 2019 Fortune Drive Lawrenceburg KY 40342 Phone Fax 502 859 5490 20 33 Baud Rate selection BO B1 Baud Rate on on 115k on off 38 4k off on 19 2k off off 1200 PARA
3. address a switch AO A4 on Command Response no checksum aA 3BOO00000ADF8010 lt CR gt lt CR gt aW0144 lt CR gt 44 lt CR gt WAIT 350 MILLISEC FOR CONVERSION TO COMPLETE aA 3BO000000ADF8010 lt CR gt lt CR gt aWOABEFFFFFFFFFFFFFFFFFF lt CR gt BE28000000FFFF274B72 lt CR gt Notice that 10 bytes were written and 10 bytes were read The first byte is the Read Scratchpad command BE and the remaining 9 bytes were send out as FF because a read of these bytes was being performed The temperature data is contained in the first two bytes of the 9 byte scratchpad plus CRC data block returned See the DS1820 specification from Dallas Semiconductor for more details on the operation of the DS1820 Note The HA5 performs the above function for DS1820s with the V command Embedded Data Systems LLC 2019 Fortune Drive Lawrenceburg KY 40342 Phone Fax 502 859 5490 16 33 READ TEMPERATURE Command y READ TEMPERATURE OF SELECTED DS1820 or DS1920 Form a V checksum lt CR gt Where a is the address character a z v is the read temperature directive The response is all eight bytes of the DS1820 DS1920 scratchpad memory and the CRC The Read temperature command performs the address selection reset convert wait reset address and read data functions required to read temperature data Example Read the temperature of a selected DS1820 address a switch AO A4 on Command Res
4. EMBEDDED HAS5 User Manual E DS DATA SYSTEMS ASCII RS232 RS485 TTL to 1 Wire Host Adapter http www EmbeddedDataSystems com HAS OPTION FEATURES ASCII command support for all 1 Wire devices RS232 RS485 or TTL interface options Parasitically RS232 or externally powered Automatically adjusts for variable 1 Wire bus conditions E S Automatically provides smart strong pull up for sensors DBY l 2000 feet 200 devices per CAT 5 twisted pair 1 Wire bus p Supports up to 26 1 Wire networks per host serial port l User selectable Baud rates from 1200 to 115K Baud __ fi ae User selectable address 1 of 26 ace ll Brae User selectable error check mode RS232 version supports Broadcast Radio and Modem applications Built in DB9 for RS232 RS485 TTL interface Optional RJ11 or screw down 1 Wire bus interface connector options Provides Search Conditional Search and Family Search commands Supports Touch Memory File Structure for iButtons Automatically generates and checks CRC16 for TMEX files Block mode commands support all 1 Wire device functions ESD Protection more than 27kV IEC801 2 Reference Model on the 1 Wire bus e Optional enclosure 4 POS FHOENI DESF POS HOENI DESCRIPTION The HAS is an RS232 RS485 or TTL to 1 Wire interface which provides an ASCII command set for embedded controller and DOS based
5. aL lt CR gt Response page 11 2E00010E2E00010D2E0001 102E00010F2E00010F2E0001102F00010D lt CR gt Embedded Data Systems LLC 2019 Fortune Drive Lawrenceburg KY 40342 Phone Fax 502 859 5490 13 33 WRITE File RECORD Command T WRITE File RECORD AT PAGE WITH CRC16 Form a lpb data c checksum lt CR gt Where a is the address character a z I is the write record directive p is the page number of the record to be written b is the byte count 1 29 data is a 0 to 28 byte hex string representing the data to write into the selected page and cis the continuation page for the next record of the file See Chapter 7 of the Book of DS19xx iButton Standards from Dallas Semiconductor for a comprehensive discussion of the Touch Memory File Structure The HA5 can only write to 1 Wire devices and iButtons in Touch Memory File Structure records However the user can directly communicate with any 1 Wire device or iButton using the block write read commands W K and J The block commands support all device functions Example Write the record HA5 is Easy To USE into the file that contains page 21 hex of the DS1996 with ROM code EF00000003B7890C address a switch AO A4 on Command Response no checksum aAEF00000003B7890C lt CR gt lt CR gt could also use F S or C commands to select al2113484135206973204561 737920544F2055534522 lt CR gt lt CR gt p 21 the
6. Calib1 Engr 2 Calib1 Raw 0 LC B 4 Calib2Engr 3 3 CIE Calib2Raw TempCalib ia TempCoeff 0 6 w oO S Second calibration in raw binary units Example 3129 Calibration Temperature for compensation ao are WN WwW game Example 19 73 Temperature Coefficient for compensation Example 2150 Table Terminator F Terminates the calibration table Designates a Real Number field Real Number fields are ASCII strings with no null terminator but with the last characters most significant byte set to indicate end of string 8 Embedded Data Systems LLC 2019 Fortune Drive Lawrenceburg KY 40342 Phone Fax 502 859 5490 28 33 Gathering Data From DS1820 1920s and DS2406 2407s Using Multiple HA5s Overview This document describes how to gather information from DS1820 1920s and DS2406 2407s using multiple HA5s through an RS485 network Please refer to the HA5 specification for more information Checksums It is highly recommended that Checksums be enabled when using HA5s in a multi drop mode For initial development Checksum mode is not required The checksum incorporates all characters in a command or response but does not include the lt CR gt Checksum must be enabled on the HA5 If Checksum mode is not enabled on the HA5 the HA5 just ignores the checksum in the command but does not send the checksum in the response In the examples Checksums are italicized Polling Methods There are two methods to poll the
7. The HA5 EDS humidity sensors contain a 12 bit analog input subsystem a DS1820 digital temperature sensor and a DS2407 with 512 bytes of ROM memory Unique device identification and calibration information is stored in the ROM memory of the embedded DS2407 The memory also contains the address code for the DS1820 used for temperature compensation Many devices can be present on the 1 Wire bus of an HA5 The user must determine the ROM codes and device types of every device on the bus When these devices are analog sensors the calibration information must re read from each device and used to calculate the engineering units of the parameter being sensed Humidity sensors are DS2407 based devices family code 12 The ROM memory will identify the device type provide the calibration constants and the ROM code of the temperature sensor used to compensate the readings The following steps are required in order to acquire Temperature compensated Relative Humidity readings in engineering units Search the 1 Wire bus for Humidity sensors Use Address command Family search Search or Conditional search commands to locate ROM codes of family code 12 Read the device ID field Use the Read Pages command examine bytes at locations 33 36 for device ID RHRH Read the DS1820 ROM address Use the Read Pages command bytes 64 71 for ROM code of temperature sensor Read the calibration information Use the Read Pages command starting at byte 79 for calib
8. page number of the file record to write to b 13 byte count of 19 decimal 13 hex 18 characters plus one for the continuation code data data 484135206973204561737920544F 20555345 HA5 is Easy To USE in ASCII hex c 22 hex the continuation code for next page of the file Embedded Data Systems LLC 2019 Fortune Drive Lawrenceburg KY 40342 Phone Fax 502 859 5490 14 33 WRITE READ BLOCK Commands W WRITE BLOCK K RESET AND WRITE BLOCK and J RESET ADDRESS DEVICE AND WRITE BLOCK Form a Wb data checksum lt CR gt or a K b data checksum lt CR gt or a J b data checksum lt CR gt Where a is the address character a z W K J ARE the block write read directives b is byte count to write and data is the block to write onto the 1 Wire bus 1 32 bytes The write read block commands are very similar to the write read bit command B The block commands performs the bit write read functions on blocks of data up to 32 bytes long The block write read commands are the most powerful of the 1 Wire commands provided by the HA5 These commands allow blocks of data either zeros 0 or ones 1 to be written or read on the bus This function is provided to allow direct manipulation of 1 Wire devices and can provide interface to all 1 Wire device functions On a 1 Wire bus the bus master HA5 writes a one 1 by setting the bus voltage low for a short time See Chapter 1 of the Boo
9. 01C8BE12 lt CR gt lt CR gt one at a time aC 01 lt CR gt 7F0000000836A410 lt CR gt aC lt CR gt 0600000001C8BE12 lt CR gt aC lt CR gt lt CR gt In the above example a D1820 DS1920 family code 10 had an alarm condition and a DS2407 family code 12 had an alarm condition pending No other devices had alarms pending See the individual device specifications for details on conditional alarm search capabilities Embedded Data Systems LLC 2019 Fortune Drive Lawrenceburg KY 40342 Phone Fax 502 859 5490 5 33 Family Search Command F FAMILY SEARCH Form a Ffl checksum lt CR gt Where a is the address character a z F is the Family Search command directive f is the family code or M to indicate search after the initial family search Family search speeds the process of selecting a specific device on the 1 Wire bus if the user knows the family code Ina network of many devices the user may wish to read for example the temperatures of all the DS1820 based sensors The family search command F10 can be used to locate the first sensor the temperature can be read with the V command Subsequent temperature sensors can be selected with the FM command and read with the V command until all temperatures have been taken indicated by a CR only response or a ROM code with a different family code response The Family Search command selects the 1 Wire device that corresponds to the ROM co
10. 1 WIRE RESET The Reset command generates a reset pulse and determines if any slave devices are on the 1 Wire bus N READ ANALOG CHANNEL Allows 12 bit analog data to be read from EDS multi channel analog input boards and sensor probes Q READ 8 ANALOG CHANNELS Allows eight 12 bit analog data channels to be read from EDS multi channel analog input boards G READ PAGES Allows any number of consecutive pages of data to be read from an iButton or 1 Wire memory device L READ FILE RECORDS Allows any number of TMEX file records of data to be read from an iButton or 1 Wire memory device T WRITE File RECORD AT PAGE WITH CRC16 Write to 1 Wire devices and iButtons in Touch Memory File Structure records WT WRITE BLOCK K RESET AND WRITE BLOCK and J RESET ADDRESS DEVICE AND WRITE BLOCK Similar to the write read bit command on blocks of up to 32 bytes y READ TEMPERATURE OF SELECTED DS1820 or DS1920 Performs a temperature conversion and reads the 8 byte scratchpad memory of a DS1820 DS1920 D READ DS2407 Channel Info Reads the channel info byte of a selected DS2407 DR READ DS2407 Channel Info with activity latch reset Resets the activity latches and reads the channel info byte of a selected DS2407 E WRITE DS2407 DIGITAL OUTPUTS Writes DS2407 digital outputs with a CRC16 error check before write Embedded Data Systems LLC 2019 Fortune Drive Lawrenceburg KY 40342 Phone Fax 502 859 5490 3 33 Searc
11. 1820 can convert the temperature in 120 ms the V command takes 500 ms For externally powered situations use the W and J commands to gather the data in the most timely and efficient manner The following illustrates how to gather temperature data using the V command Commands Reponses lt use the S or A commands to select device gt qVC7 lt CR gt 29000000FFFF214B9BF7 lt CR gt The response is a 9 byte string 8 scratchpad bytes and a CRC The temperature data is contained in the first two bytes of the 9 byte scratchpad plus CRC data block returned The data is as follows TEMP 0029h 41 dec bytes 1 amp 2 where byte 1 is LSB C_REMAIN 21h 83 dec byte 7 C_CNT 4Bh 75 dec byte 8 CRC 33h 51 dec byte 9 Temperature Temp 2 in degrees C For higher resolution use the following equation float TValue float short Temp amp OxFFFE 2 if Cnt_C 0 error Temperature TValue 0 25 Cnt_C Cnt_Remain Cnt_C For ultimate integrity of the data the CRC should be used to verify the contents of the data See the section Calculating CRC 16 and CRC 8 for information on calculating CRC 8s For more information please consult the specification for the DS1820 Gathering I O from the DS2406 Use the D and the DR command to read the I O states of the DS2406 The DS2406 has an activity latch that can be reset with the DR command The following illustrates reading the I O data Commands Reponses aDA5 lt CR gt 7
12. 24 250 164 39 121 155 197 132 218 56 102 229 187 89 7 219 133 103 57 186 228 6 88 25 71 165 251 120 38 196 154 101 59 217 135 4 90 184 230 167 249 27 69 198 152 122 36 248 166 68 26 153 199 37 123 58 100 134 216 91 5 231 185 140 210 48 110 237 179 81 15 78 16 242 172 47 113 147 205 17 79 173 243 112 46 204 146 211 141 111 49 178 236 14 80 175 241 19 77 206 144 114 44 109 51 209 148 12 82 176 238 50 108 142 208 83 13 239 177 240 174 76 18 145 207 45 115 202 148 118 40 171 245 23 73 8 86 180 234 105 55 213 139 87 9 235 181 54 104 138 212 149 203 41 119 244 170 72 22 233 183 85 11 136 214 52 106 43 117 151 201 74 20 246 168 116 42 200 150 21 75 169 247 182 232 10 84 215 137 107 53 Begin CRC8 Table CRC8 xor X End Embedded Data Systems LLC 2019 Fortune Drive Lawrenceburg KY 40342 Phone Fax 502 859 5490 33 33
13. F7D lt CR gt lt is activity latch set Yes the send DR command to reset latch gt aDRF7 lt CR gt 4F 7A lt CR gt The data is as follows Output A bit 1 Output B bit 2 Current Sensed Input A bit 3 Current Sensed Input B bit 4 ActivityLatch A bit 5 ActivityLatch B bit 6 Embedded Data Systems LLC 2019 Fortune Drive Lawrenceburg KY 40342 Phone Fax 502 859 5490 31 33 The D and DR commands do not check the CRC16 error check that is returned from the DS2406 The response of the D or DR commmands is vulnerable to errors on the 1 Wire bus If you need error checking you can use the block commands to communicate directly with the DS2406 You will then need to process the CRC16 error check yourself The following illustrates using the block command to obtain the I O data Commands Reponses aW07F55DFFFFFFFFFF33 lt CR gt F55DFF7FFF300632 lt CR gt lt reset latch and read inputs gt aW07F5DDFFFFFFFFFF33 lt CR gt F5DDFF6FFF140662 lt CR gt The data is as follows Channel Info Byte byte 3 ex 7Fhex OutputA bit 0 1 OutputB bit 1 1 SensedA bit 2 1 SensedB bit 3 1 LatchedA bit 4 1 LatchedB bit 5 1 No Channels bit 6 1 Supply bit 7 0 CRC16 byte 5 ex O630hex For more information please consult the specification for the DS2406 2407 Setting the Outputs of the DS2406 Use the E command to set the outputs of the DS2406 The HA5 error checks the communications if there is an error in the communications HA5 will not attempt to set t
14. FF hex The n parameter is optional after the initial conditional search When the n parameter is not included the search is continued from the last search pass the response is at most one ROM code or a lt CR gt indicating end of ROM code search The Conditional Search ROM command operates similarly to the Search command except that only those devices fulfilling a specific device dependent condition will participate in the search This is a very powerful functional aspect of 1 Wire devices This capability provides for very fast and efficient polling of the 1 Wire bus for devices that have activity of interest See the individual device specifications from Dallas Semiconductor for details on the conditional search capability of a specific 1 Wire device The Conditional Search ROM command selects the 1 Wire device that corresponds to the ROM code sent to the host last as aresponse Devices may also be selected with the A address S search or F family search commands Once selected all commands will operate on the selected device until another device is selected Example Search for all slave devices on the bus fulfilling the respective conditions for conditional search address a switch AO A4 on Note each 1 Wire device family may or may not support conditional search see the individual device specifications for details Command Response no checksum aC FF lt CR gt 7F0000000836A410 lt CR gt 06000000
15. METER SYMBOL MN TYP _ MAX _ UNITS Supply Voltage Supply Current po A 1 Wiredevices 200 devices CAT 5 Cable length eo 2000 Baud Rate S a Embedded Data Systems LLC 2019 Fortune Drive Lawrenceburg KY 40342 Phone Fax 502 859 5490 21 33 SWITCH DEFINITIONS SWITCH DESCRIPTION 1 B 0 Baud selection bit0 see table below 2 B1 Baud selection bit1 see table below 3 Checksum enable on enables checksum mode 4 A4 address select bit 4 weight of 16 when off see table below 5 A3 address select bit 3 weight of 8 when off see table below 6 A2 address select bit 2 weight of 4 when off see table below 7 A1 address select bit 1 weight of 2 when off see table below 8 AO address select bit 0 weight of 1 when off see table below Address Switch Selection A4 A3 A2 A1 AO Address on on on on on a on on on on b on on on on c on on on q on on on on e on on on T on on on g on on h on on on on on on on j on on on k on on pP on on on m on on n on on o on p on on on on q on on on ga on on on s on on p on on on u on on y on on w on X on on on y on on Z Embedded Data Systems LLC 2019 Fortune D
16. Systems LLC 2019 Fortune Drive Lawrenceburg KY 40342 Phone Fax 502 859 5490 9 33 READ ANALOG CHANNEL Command N READ ANALOG CHANNEL Form a Nn checksum lt CR gt Where a is the address character a z N is the read analog channel directive and nis the analog channel 0 7 of a EDS 12 bit analog device Note that for probe devices only channel 0 is valid The Read Analog Channel command allows 12 bit analog data to be read from EDS multi channel analog input boards and sensor probes Example Read channel 2 the third channel of the TBA 8 channel 12 bit analog input board with ROM code 2400000007377212 address a switch AO A4 on Command Response no checksum aA2400000007377212 lt CR gt lt CR gt could also use F S or C commands to select aN02 lt CR gt 07FE lt CR gt 2 496 Volts Embedded Data Systems LLC 2019 Fortune Drive Lawrenceburg KY 40342 Phone Fax 502 859 5490 10 33 READ 8 ANALOG CHANNEL Command Q READ 8 ANALOG CHANNELS Form a Q checksum lt CR gt Where a is the address character a z Q is the read 8 analog channel directive The response is all eight analog channels 0 7 of a EDS 12 bit analog device Note that for probe devices this command is not valid The Read 8 Analog Channel command allows eight 12 bit analog data channels to be read from EDS multi channel analog input boards with a single command Exam
17. applications that need to accommodate Dallas Semiconductor iButton and 1 Wire devices The HA5 relieves the host of the burden of generating the time critical 1 Wire communication waveforms while supporting all 1 Wire devices with simple ASCII commands that can be easily generated The HA5 does all the hard work of interfacing 1 Wire networks RS232 RS485 and TTL versions provide as many as 26 1 Wire networks from a single host serial port broadcast radio or modem The HA5 can perform Search Conditional search and Family search functions making it easy to acquire the unique 64 bit serial numbers of all connected devices The HA5 constantly performs a dynamic analysis of the network and adjusts the network timing to allow for variable conditions This results in good performance with both short and long networks with many or only a few devices attached Many sensor devices require that extra power be delivered during periods of data conversions DS1920 and DS1820 temperature sensors for example The HA5 automatically provides the extra current these devices require with a built in smart strong pull up Dallas Semiconductor iButtons which store data in TMEX Touch Memory File format can be read or written with simple ASCII commands The HA5 will automatically generate and check the CRC16 error checks from Touch Memory File records The HA5 supports analog digital and temperature 1 Wire devices and all Dallas Semiconductor iButtons 1 Wire and iButton a
18. de sent to the host last as a response Devices may also be selected with the A address S search or C conditional search commands Once selected all commands will operate on the selected device until another device is selected Example Search for all DS1820 DS9120 temperature sensor devices on the bus family code 10 and read the temperature data with the V command address a switch AO A4 on Note After the first selection of a device with the desired family code subsequent searches must be made with the FM command until a lt CR gt only is returned indicating that all have been found Command Response no checksum aF10 lt CR gt 7F0000000836A410 lt CR gt aV lt CR gt 2D000000FFFF1F4DA2 lt CR gt see V command for details aFM lt CR gt A00000000B14E710 lt CR gt aV lt CR gt 2D000000FFFF1F4DA2 lt CR gt aFM lt CR gt lt CR gt no more fc 10 Note It can be seen from this example that the host does not need to maintain the ROM codes of the devices in the network in order to acquire data and communicate with them This example uses the family search command to select the DS1820 DS1920 devices and the V command to acquire the temperature data Embedded Data Systems LLC 2019 Fortune Drive Lawrenceburg KY 40342 Phone Fax 502 859 5490 6 33 ADDRESS Select Command A ADDRESS Select Form a AROM CODE checksum lt CR gt Where a is the address character a
19. devices attached on the HA5s The first method uses the search command to select the device This method allows you to be flexible about the number of devices attached to the network The second method uses the search commands to obtain the serial numbers of the devices attached to the HA5 The serial numbers are stored then used to address each device one at atime This method is useful when the number of devices is not expected to change Finding HA5s If an HA5 is not present or the command is not received because of communication errors no response may be given The Host should be prepared to time out if no response is given The HA5 will respond with an error code BEL hex 07 followed by a lt CR gt if an error is encountered while attempting to execute the given command To find the HA5s attached try sending the search command to all 26 potential addresses The following illustrates Commands Reponses aS 0141 lt CR gt 7F0000000836A41044 lt CR gt bS 0142 lt CR gt A00000000B14E71045 lt CR gt cS 0143 lt CR gt nothing wait for timeout zS 015A lt CR gt nothing wait for timeout Other commands can be used to determine if the HA5 is there like the Reset Command ee Embedded Data Systems LLC 2019 Fortune Drive Lawrenceburg KY 40342 Phone Fax 502 859 5490 29 33 Family Codes DS1820 1920 have family code of 10hex and DS2406 2407 have family code of 12hex Polling Method 1 This method uses the search command to selec
20. ecksum lt CR gt Where a is the address character a z B is the bit write read directive and vis the bit value 0 or 1 to write on the bus The bit write read command is the lowest level 1 Wire command This command allows a single bit either zero 0 or one 1 to be written or read on the bus This function is provided to allow direct manipulation of 1 Wire devices and is not normally required On a 1 Wire bus the bus master HA5 writes a one 1 by setting the bus voltage low for a short time See Chapter 1 of the Book of DS19xx iButton Standards from Dallas Semiconductor for details A bus master writes a zero 0 by setting the bus voltage low for a longer time When a slave device needs to communicate a one 1 bit it simply does nothing during the bus master write of a one 1 time slot When a slave device needs to communicate a zero 0 bit it holds the bus master write one 1 time slot low for the longer time indicative of a zero 0 time slot This allows the slave device to communicate both zero and one bits without the need to drive the bus The 1 Wire bus master does the bus driving A slave device only needs to hold the bus low during time slots that it wishes to communicate a zero 0 bit value The only conditions under which the slave drives the bus is during reset presence The B command is both a write bit and read bit command When the bus master is writing bits both BO and B1 com
21. ee Chapter 5 of the Book of DS19xx iButton Standards from Dallas Semiconductor for a comprehensive discussion of the search ROM function The Search ROM command selects the 1 Wire device that corresponds to the ROM code sent to the host last as a response Devices may also be selected with the A address C conditional search or F family search commands Once selected all commands will operate on the selected device until another device is selected Example Read the ROM codes of all slave devices on the bus address a switch AO A4 on Command Response no checksum aS FF lt CR gt 7F0000000836A410 lt CR gt A00000000B14E710 lt CR gt 0600000001C8BE12 lt CR gt lt CR gt with checksum aS FF6C lt CR gt 7F0000000836A41044 lt CR gt A00000000B14E71045 lt CR gt 0600000001C8BE124C lt CR gt lt CR gt to take the ROM codes one at a time With checksum aS 0141 lt CR gt 7F0000000836A41044 lt CR gt aSB4 lt CR gt A00000000B14E71045 lt CR gt aSB4 lt CR gt 0600000001 C8BE124C lt CR gt aSB4 lt CR gt lt CR gt Embedded Data Systems LLC 2019 Fortune Drive Lawrenceburg KY 40342 Phone Fax 502 859 5490 4 33 Conditional Alarm SEARCH Command C CONDITIONAL SEARCH ALARM SEARCH Form a C n checksum lt CR gt Where a is the address character a z C is the Conditional Search command directive n is an optional maximum ROM codes to send from an initial search 01 to
22. ere AnalogValue value read from the analog sensor input CurrentTemp value read from the attached temperature sensor DS1820 TempCalib Calibrated temperature value located in the probe s OTP TempCoeff Temperature coefficient in parts per million located in the probe s OTP Engineering Unit Conversion Once the analog reading has been obtained and compensated for temperature the bus master will need to apply the available calibration information to convert the reading to engineering units Use the following formula to convert to engineering units Scale Calib2Engr Calib1Engr Calib2Raw Calib1 Raw Offset Calib1Engr Calib1 Raw scale EngrValue BinaryValue Scale Offset Example Below Scale 100 0 3129 OC39h 717 O2CDh 100 2114 04146 Offset 0 717 04146 29 73 AnalogValue 0640h 1600 dec CurrentTemp 20 5 deg C TempCalib 25 0 deg C TempCoeff 2150 ppm 0866h EngrValue 1600 0640h 04146 29 73 36 6 Relative Humidity ValueComp 36 6 1 20 5 25 0 2150 1000000 36 25 Relative Humidity compensated Note As can be seen from this example if the temperature of the environment is relatively stable you may not need to perform the temperature compensation Embedded Data Systems LLC 2019 Fortune Drive Lawrenceburg KY 40342 Phone Fax 502 859 5490 26 33 Search the 1 Wire bus for Humidity sensors Use Family Search command to find ROM code of DS2407 Command Re
23. erform a bus reset first and then operate just like the W form The J form will reset the bus address the last selected device and then operate just like the W form of the write read block command These commands along with the search commands may be all the function many applications will require See examples below of the use of the block write read commands Embedded Data Systems LLC 2019 Fortune Drive Lawrenceburg KY 40342 Phone Fax 502 859 5490 15 33 WRITE READ BLOCK Command Examples Example Select the DS2407 with ROM code 2400000007377212 issue the Channel Access command and read the Channel Info Byte which contains the input latches output latches and sensed levels of the two I O lines PIOA PIOB address a switch AO A4 on Command Response no checksum aA2400000007377212 lt CR gt lt CR gt aW04F5CFFFFF lt CR gt F5CFFF47 lt CR gt Note 4 bytes were written and 4 bytes were read The last byte written FF is a read byte corresponding to the reading of the Channel Info Byte in the DS2407 See the DS2407 specification from Dallas Semiconductor for more details on the operation of the DS2407 Note The HA5 performs the above function for DS2407 slaves with the D and DR commands Example Select the DS1820 with ROM code 3BO000000ADF8010 issue the Convert Temperature command and wait at least 350 millisec Then read the 8 byte scratchbad memory which contains the temperature data
24. h ROM Command S SEARCH ROM Form a S n checksum lt CR gt Where a is the address character a z S is the Search command directive n is an optional maximum ROM codes to be sent from an initial search 01 to FF hex The n parameter is optional after the initial search When the n parameter is not included the search is continued from the last search pass the response is at most one ROM code or a lt CR gt indicating end of ROM code search When a system is initially brought up the host application might not know the number of devices on the 1 Wire bus or their 64 bit ROM codes The Search ROM command allows the HA5 to use a process of elimination to identify the 64 bit ROM codes of all slave devices on the bus The Search ROM process is the repetition of a simple 3 step routine read a bit read the complement of the bit then write the desired value of that bit The HA5 performs this simple 3 step routine on each bit of the ROM After one complete pass the HA5 knows the contents of the ROM in one device The 64 bit ROM code is then reported as an 8 byte ASCII hexadecimal string Additional passes may identify the remaining number of devices and their ROM codes The HA5 Search ROM command will find the ROM codes of one all or a subset of the available slave devices on the bus The host application can remember these ROM codes for future references to selected slave devices with the A address command S
25. he output The follow is an example of setting the output Commands Reponses lt set outputs to 1 gt aE66 12 lt CR gt 666C lt CR gt lt set outputs to 0 gt aE060C lt CR gt 0666 lt CR gt aE060C lt CR gt lt BEL gt The outputs are located in bit 5 for A and bit 6 for B Consult the Dallas DS2407 specification for the meaning of the other bits in the Status Ram location 7 Embedded Data Systems LLC 2019 Fortune Drive Lawrenceburg KY 40342 Phone Fax 502 859 5490 32 33 Calculating CRC 16 and CRC 8 Here is a Pascal routine to calculate CRC16 Var CRC16 Word This procedure accumulates the CRC16 CRC of the data X in the global variable CRC16 Procedure TMainForm DoCRC16 X Byte Var Byte F Boolean Begin For 1 to 8 do Begin F Odd X xor CRC16 CRC16 CRC16 shr 1 X X shr 1 If F then CRC16 CRC16 xor A001 End End CRC 8 Here is a pascal routine to calculate CRC8 Var CRC8 smallint This procedure calculates the cumulative Dallas Semiconductor one wire CRC8 of all bytes passed to it The result accumulates in the global variable CRC8 Procedure TMainForm DoCRC8 x Byte Const Table Array 0 255 of Byte 0 94 188 226 97 63 221 131 194 156 126 32 163 253 31 65 157 195 33 127 252 162 64 30 95 1 227 189 62 96 130 220 35 125 159 193 66 28 254 160 225 191 93 3 128 222 60 98 190 224 2 92 223 129 99 61 124 34 192 158 29 67 161 255 70
26. k of DS19xx iButton Standards from Dallas Semiconductor for details A bus master writes a zero 0 by setting the bus voltage low for a longer time When a slave device needs to communicate a one 1 bit it simply does nothing during the bus master write of a one 1 time slot When a slave device needs to communicate a zero 0 bit it holds the bus master write one 1 time slot low for the longer time indicative of a zero 0 time slot This allows the slave device to communicate both zero and one bits without the need to drive the bus The 1 Wire bus master does the bus driving A slave device only needs to hold the bus low during time slots that it wishes to communicate a zero 0 bit value The W K AND J commands are both write block and read block commands The bus master always writes even when reading The bus master writes 1 time slots whenever it wishes to write a 1 bit or when it wishes to read a bit from a selected slave When reading a bit the response to a write 1 time slot may be either 0 or 1 depending on weather or not the slave device holds the bus low to indicate a 0 bit The block write read commands will send up to 32 bytes of 8 bits each onto the 1 Wire bus and record the slave response and send it back as a command response This is a very powerful and efficient technique for communicating with 1 Wire slaves The W form simply writes the block and records the response The K form will p
27. mands apply When the bus master is reading bits only the B1 command applies When reading a bit the response to a B1 command may be either 0 or 1 depending on weather or not the slave device holds the bus low to indicate a O bit The block commands W K and J perform this same function on blocks of data Example Write a zero 0 on the bus address a switch AO A4 on Command Response write a 0 bit no checksum aB0 lt CR gt 0 lt CR gt write a 1 bit aB1 lt CR gt 1 lt CR gt read a 1 bit aB1 lt CR gt 1 lt CR gt read a 0 bit aB1 lt CR gt 0 lt CR gt Embedded Data Systems LLC 2019 Fortune Drive Lawrenceburg KY 40342 Phone Fax 502 859 5490 8 33 RESET Command R 1 WIRE RESET Form a R checksum lt CR gt Where a is the address character a z R is the RESET directive The Reset command generates a reset pulse and determines if any slave devices are on the 1 Wire bus IF any slave is present it will generate a presence pulse in response to the reset The HA5 detects this presence pulse and reports it as a P If no presence pulse is returned the HA5 returns a N Example Reset the 1 Wire bus and determine if any slave devices are present address a switch AO A4 on Command Response no checksum aR lt CR gt P lt CR gt slaves present aR lt CR gt N lt CR gt no slaves present Embedded Data
28. oes not have to be the starting page of the TMEX file The n parameter is the maximum number of consecutive file records not necessarily consecutive pages to be read CRC16 is checked on the record and if the record is not a valid Touch Memory File record an error code BEL 07 is generated and the read process stops The byte count continuation code and CRC16 bytes are stripped from the file record before it is sent The HA5 uses the continuation code to determine the page number of the next record of the file end of file is marked with a continuation code of zero 0 The read process continues until n records are read or the end of the file is reached as is indicated by a continuation code of zero A CR only response from the HA5 indicates that the end of the file was encountered See Chapter 7 of the Book of DS19xx iButton Standards from Dallas Semiconductor for a comprehensive discussion of the Touch Memory File Structure Example Read two records of a file starting at page OF from the DS1996 with ROM code EF00000003B7890C Then read the next record of the file after these two address a switch AO A4 on Command Response no checksum aAEF00000003B7890C lt CR gt lt CR gt could also use F S or C commands to select aL 020F lt CR gt Response these are pages OF and 10 2E0001142E0001142E0001132E0001112E0001132E0001122E000112 lt CR gt 2E0001 102E00010F2E0001 112F00010F2E00010E2E0001102E00010E lt CR gt
29. oth activity latches See the DS2407 specification from Dallas Semiconductor for more details on the operation of the DS2407 Embedded Data Systems LLC 2019 Fortune Drive Lawrenceburg KY 40342 Phone Fax 502 859 5490 18 33 WRITE DS2407 DIGITAL OUTPUTS Command E WRITE DS2407 DIGITAL OUTPUTS Form a Ev checksum lt CR gt Where a is the address character a z E is the write DS2407 status memory location 7 directive and vis the 8 bit value to be written The response is the data written or an error code BEL 07 hex indicating that the CRC16 did not check and no output changes were made Example Set both PIO A and PIO B of the selected DS2407 to the non conductive off high state and set the search conditions so that this DS2407 will participate in a conditional search if either of the activity latches for PIO A or PIO B are 1 note that the activity latches can be reset with the DR command Take care with this command The DS2407 can be placed in hidden mode if both bit 1 and bit 2 of status memory location 7 are set to zero 0 the DS2407 will enter a Hidden Mode where it will only respond to conditional search commands This mode can be changed if the user knows the 64 bit ROM code of the part See the DS2407 specification from Dallas Semiconductor for more details on the operation of the DS2407 address a switch AO A4 on Command Response no checksum aE7B lt CR gt 7B lt CR gt
30. ple Read 8 channels of the TBA 8 channel 12 bit analog input board with ROM code 2400000007377212 address a switch AO A4 on Command Response no checksum aA2400000007377212 lt CR gt lt CR gt could also use F S or C commands to select aQ lt CR gt 0000000007FE00000000000000000000 lt CR gt The data is returned as 16 hexadecimal bytes two bytes for each channel of 0000 0FFF values Embedded Data Systems LLC 2019 Fortune Drive Lawrenceburg KY 40342 Phone Fax 502 859 5490 11 33 READ PAGES Command G READ PAGES Form a G np checksum lt CR gt Where a is the address character a z G is the read page directive nis the number of pages to read and p is the starting page number The response is 32 bytes in hexadecimal read from the memory of the selected iButton or 1 Wire memory device for each of the number of consecutive pages determined by the n parameter The n and p parameters may be omitted this results in a single page read of the next page The Read Pages command allows any number of consecutive pages of data to be read from an iButton or 1 Wire memory device No assumptions are made about the nature of the contents of the pages See the L read file records command for details on how to read Touch Memory File TMEX records Example Read two pages of data starting at page OF from the DS1996 with ROM code EF00000003B7890C Read two more consecutive page
31. ponse no checksum aV lt CR gt 29000000FFFF214B9B lt CR gt Note the response is a 9 byte string 8 scratchpad bytes and a CRC The temperature data is contained in the first two bytes of the 9 byte scratchpad plus CRC data block returned See the DS1820 specification from Dallas Semiconductor for more details on the operation of the DS1820 Embedded Data Systems LLC 2019 Fortune Drive Lawrenceburg KY 40342 Phone Fax 502 859 5490 17 33 READ DS2407 Channel Info Command D READ DS2407 Channel Info DR READ DS2407 Channel Info with activity latch reset Form a D checksum lt CR gt or a DR checksum lt CR gt Where a is the address character a z D is the read DS2407 channel info byte directive DR is the read DS2407 channel info byte with activity latch reset directive The response is the channel info byte of the selected DS2407 The DR form will reset the activity latch before reading the channel info byte the D form will not Example Read the channel info byte of the selected DS2407 then reset the activity latchs address a switch AO A4 on Command Response no checksum aD lt CR gt 7F lt CR gt aDR lt CR gt 4F lt CR gt Notice that the bits 4 and 5 of the response are set in the first example This indicates that the activity latches for PIO A and PIO B are set The DR command read the channel info byte again after performing an activity latch reset which resets b
32. ration constants see table below Read the Current Temperature Use the Address command with the acquired DS1820 ROM code to acquire the temperature data Read the analog Humidity data Use the N or Q command to read the analog value Calculate the current temperature From the V command response the first byte is the LSB of the 9 bit temperature reading the second byte is the MSB The most significant sign bit is duplicated into all of the bits in upper MSB of the two byte temperature reading This sign extension yields the 16 bit temperature readings shown below Temperature Output Binary Output Hex 125 deg C 00000000 11111010 OOFA 25 deg C 00000000 00110010 0032 1 2 deg C 00000000 00000001 0001 0 deg C 00000000 00000000 0000 1 2 deg C 11111111 11111111 FFFF 25 deg C 11111111 11001110 FFCE 55 deg C 1111111110010010 FF92 Embedded Data Systems LLC 2019 Fortune Drive Lawrenceburg KY 40342 Phone Fax 502 859 5490 25 33 Temperature Compensation The humidity sensor contains a DS1820 digital temperature sensor the humidity sensor will need its analog reading compensated for variations in temperature Before or after the humidity sensor s analog value is read the temperature is read from the temperature sensor DS1820 Use the following formula to compensate the sensor reading for the measured temperature ValueComp AnalogValue 1 Currenttemp TempCalib TempCoeff 1000000 Wh
33. re registered trademarks of Dallas Semiconductor TMEX is a trademark of Dallas Semiconductor L Embedded Data Systems LLC 2019 Fortune Drive Lawrenceburg KY 40342 Phone Fax 502 859 5490 1 33 HA5 Command format Command Response Address command Checksum CR Data Checksum CR The HA5 is an addressed command response device To get a response the user must send a command with the proper address command and checksum The HA5 will respond with data and a checksum All commands and responses end with a CR hex OD character The Address is a single character a to z which is set by onboard switch positions A0 A4 The checksum is a mod 256 sum of all the ASCII character values in the command or response but does not include the CR For development purposes the user can disable the checksum in this case the checksum field is not present in either the command or the response All commands data and checksums are in ASCII hexadecimal format Each HA5 on the host serial port in a broadcast radio network or on a TTL connection must have the address switches A0 A4 set to a unique setting This allows as many as 26 1 Wire busses to be created from a single serial port Each HA5 will respond to the unique single character a z address resulting from the switch settings AO A4 see address switch table In RS232 mode the HA5 uses the address capability to support broadcast radio applications In RS485 and TTL modes
34. rive Lawrenceburg KY 40342 Phone Fax 502 859 5490 22 33 Package Options and Part Number Format SEE NEXT PAGE FOR PART FORMAT ee Embedded Data Systems LLC 2019 Fortune Drive Lawrenceburg KY 40342 Phone Fax 502 859 5490 23 33 Embedded Data Systems Part Format HA5 One Six License Key K Keyed Not Present No Key Enclosure Option E ABS Enclosure Not Present None 1 Wire Connector Type N None P Phoenix R Dual RJ11 Host Connector Type D DB9 only option available on website N None P Phoenix Host Communication TIL TTL 232 RS232 485 RS485 Part Examples HA5 232 No Connectors No Enclosure No Key HA5 232 Host Con DB9 1 Wire Con Dual RJ11 No Enclosure Keyed HA5 485 Host Con Phoenix 1 Wire Con Phoenix ABS Enclosure No Key HAS TTL Host Con Phoenix 1 Wire Con Dual RJ11 No Enclosure Keyed HA5 232 Host Con DB9 1 Wire Con Dual RJ11 ABS Enclosure Keyed Embedded Data Systems LLC 2019 Fortune Drive Lawrenceburg KY 40342 Phone Fax 502 859 5490 24 33 Using EDS 1 Wire Relative Humidity Sensors With
35. s one at a time address a switch AO A4 on Command Response no checksum aAEF00000003B7890C lt CR gt lt CR gt could also use F S or C commands to select aG 020F lt CR gt Response these are pages OF and 10 1D2E0001142E0001142E0001132E0001112E0001132E0001122E00011210CA42 lt CR gt 1D2E0001102E00010F2E0001 1 12F00010F2E00010E2E0001102E00010E1 16488 lt CR gt aG lt CR gt Response page 11 1D2E00010E2E00010D2E0001102E00010F2E00010F2E0001102F00010D12A299 lt CR gt aG lt CR gt Response page 12 1D2E00010D2E00010E2E00010F2E00010D2F0001122F0001122F00011313BBD0 lt CR gt Embedded Data Systems LLC 2019 Fortune Drive Lawrenceburg KY 40342 Phone Fax 502 859 5490 12 33 READ FILE RECORDS Command L READ FILE RECORDS Form a L np checksum lt CR gt Where a is the address character a z L is the read file directive n is the number of records to read and p is the starting page number The response is 28 bytes or less in hexadecimal read from the memory of the selected iButton or 1 Wire memory device for each of the number of consecutive pages determined by the n parameter The n and p parameters may be omitted this results in a single read from the next file record The Read File Records command allows any number of TMEX file records of data to be read from an iButton or 1 Wire memory device The starting page p parameter must be a page number of a valid TMEX file it d
36. sponse aF12 lt CR gt B30000000DAAAC12 lt CR gt Read the device ID field aG 0101 1D52485248646D24D924234D355A2400000024FFFF24FFFF2439383433009E52 Humidity device ID RHRH 52485248 ASCII hex Read the DS1820 ROM address Read the calibration information aG 0102 810000001D500D10000000F908015EB002CD3130B00C3932352EB00866FF784F Temperature sensor ROM code calibration constants see table below Read The CurrentTemp aA810000001D500D10 lt CR gt lt CR gt could also use F S or C commands to select aV lt CR gt 29000000FFFF214B9B lt CR gt Output Binary Output Hex Temperature 00000000 00101001 0029 20 5 deg C Read the analog Humidity data aAB30000000DAAAC 12 lt CR gt lt CR gt could also use F S or C commands to select aN00 lt CR gt 0640 lt CR gt Embedded Data Systems LLC 2019 Fortune Drive Lawrenceburg KY 40342 Phone Fax 502 859 5490 27 33 Calibration Information and Identification Addr Size Function Ex Description In hex DS2407 ROM Data For Humidity Sensors Device ID field 33 4 Device ID 52 Used to determine type of device 48 RHRH relative humidity 52 48 Temperature sensor ROM code DS1820 ROM ROM address of the DS1820 attached Addr 0 Calibration Table First calibration in engineering units Example 0 2 First calibration in raw binary units D Example 717 1 Second calibration in engineering units 0 0 Example 100 6 F 79
37. t the device The following illustrates Commands Reponses aS 0141 lt CR gt 7F0000000836A41044 lt CR gt Send command to device aS B4 lt CR gt A00000000B14E71045 lt CR gt Send command to device aS B4 lt CR gt lt CR gt no more devices lt start again with another HA5 gt Polling Method 2 This method uses the search commands to obtain the serial numbers of the devices attached to the HA5 The serial numbers are stored and then used to address each device one at atime This method is useful when the number of devices is not expected to change The following illustrates Commands Reponses aS FF6C lt CR gt 7F0000000836A41044 lt CR gt A00000000B14E71045 lt CR gt 0600000001 C8BE124C lt CR gt lt CR gt lt store received serial numbers and HA5 address gt qS FF 7C lt CR gt last HA5 880000000836A41037 lt CR gt EA0000001C8BE123C lt CR gt lt CR gt lt store received serial numbers and HA5 address gt aA7F0000000836A410E6 lt CR gt 7F0000000836A41044 lt CR gt Send command to device continue for each address received qA880000000836A410E9 lt CR gt 880000000836A41037 lt CR gt Send command to device L Embedded Data Systems LLC 2019 Fortune Drive Lawrenceburg KY 40342 Phone Fax 502 859 5490 30 33 Gathering Temperature Data DS1820 For DS1820s that are powered parasitically use the V command to obtain the temperature data The V command can be used with externally powered DS1820s except that the DS
38. the address is used to enable a selected HA5 which is hard wired to the host serial port Address mode cannot be disabled An application that needs only a single HAS still must send the correct address a z which results in a match with the corresponding address switches A0 A4 The HA5 will respond with an error code BEL hex 07 followed by a lt CR gt hex OD if an error is encountered while attempting to execute the given command No response is given to commands that are addressed to another device or that have errors resulting in a checksum failure Host receive timeout is the suggested manner of recovery from these errors Error Format Command Response Address command Checksum CR BEL Checksum CR Embedded Data Systems LLC 2019 Fortune Drive Lawrenceburg KY 40342 Phone Fax 502 859 5490 2 33 HA5 Command List S SEARCH ROM Allows the HA5 to use a process of elimination to identify the 64 bit ROM codes of all slave devices on the bus C CONDITIONAL SEARCH ALARM SEARCH Search command except that only devices fulfilling a specific condition will participate in the search F FAMILY SEARCH Search command except that only the device with a matching family code will participate in the search A ADDRESS Select Selects a device on the 1 Wire bus with a matching 64 bit ROM code B WRITE READ BIT This command allows a single bit either zero 0 or one 1 to be written or read on the bus R

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