SDM-CAN Datalogger-to-CANbus Interface Revision: 8/13 C o p y r i g h t © 2 0 0 1 - 2 0 1 3 C a m p b e l l S c i e n t i f i c , I n c .
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Table of Contents PDF viewers: These page numbers refer to the printed version of this document. Use the PDF reader bookmarks tab for links to specific sections. 1. Introduction .................................................................1 1.1 1.2 General Description .............................................................................1 Specifications .......................................................................................2 1.2.1 General Features and Specifications ............
Table of Contents 3.3.10 Multiplier (Parameter 13:).......................................................... 25 3.3.11 Offset (Parameter 14:) ................................................................ 25 3.4 Advanced Programming Techniques................................................. 25 3.4.1 Interrupts Using the I/O Connection .......................................... 25 3.4.2 Group Trigger............................................................................. 27 3.4.
Table of Contents C.4 Retrieving J1939 Accelerator Pedal Position Data using a CR9000/CR5000 (Bus Speed 250k Baud)....................................C-2 C.4.1 Encoding the Identifier Field Values ........................................C-2 C.4.2 Finding the Start Bit..................................................................C-3 C.5 Retrieving J1939 Accelerator Pedal Position Data using a CR23X/CR10X (Bus Speed 250k Baud)......................................C-4 C.5.
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SDM-CAN Datalogger-to-CANbus Interface 1. Introduction The SDM-CAN interface is designed to allow a Campbell Scientific datalogger to sample data directly from a CAN-Bus communications network and thereby allow such data to be stored along with, and in synchronization with, other data values measured directly by the datalogger. To use the SDM-CAN device it is assumed that you have a full working understanding of the CAN network you wish to monitor.
SDM-CAN Datalogger-to-CANbus Interface By this process the SDM-CAN can capture data on the CAN-Bus and filter out packets of interest to the user. Within each data packet the device is able to read one or more data values and convert them to numeric values compatible with the normal data stored by the datalogger. The SDM-CAN will act as a passive listen-only device with its transmitter disabled in hardware.
SDM-CAN Datalogger-to-CANbus Interface • Additional I/O port for signaling to the datalogger that data is available, e.g. using an interrupt function. • Has a 9 pin, DCE RS232 port with auto baud rate detection (1200 to 115200) for diagnosis and operating software download. • Standard operating temperature range (tested), -25ºC to +50ºC. Can be used over an extended temperature range – contact Campbell Scientific for details. • High speed block mode for fast data collection.
SDM-CAN Datalogger-to-CANbus Interface • Where the DC-DC converter is not used, and power is provided to the isolated CAN driver circuits by an external source, the current drain by the SDM-CAN is approximately 50 mA lower than the figures quoted above. • Typical active current, non-isolated with the CAN-Bus in the recessive state: 30mA.
SDM-CAN Datalogger-to-CANbus Interface Please see Section 3, Programming CR10X, CR7 and CR23X Dataloggers to use the SDM-CAN, before using address F (33 base 4) as this address is often used as a ‘group trigger’ to synchronize measurements by several SDM devices. The switch is positioned on the right-hand side of the case, so you may have to remove the mounting bracket to gain access to this switch. TABLE 2-1. Switch Position and Addresses 2.
SDM-CAN Datalogger-to-CANbus Interface 3) If running in isolated mode decide whether the SDM-CAN will supply power via a built-in DC-DC converter for the isolated CAN interface components, or whether power will be sourced from an external supply. Using a converter adds 40-50mA to the power consumption of the SDMCAN when it is active. However, if a converter is not used, power must be provided from elsewhere (see below).
SDM-CAN Datalogger-to-CANbus Interface Transmission of CAN data is hardware disabled by default. To enable transmission, move the jumper to the TX enable position. SDM-CAN PCB Once the case lid has been removed. OBSERVE ANTISTATIC PRECAUTIONS. This jumper block is used to select isolated or nonisolated CAN-Bus interface. The jumper block can be removed and rotated so that the red bar is nearest to the mode arrow head. The default is for isolation enabled.
SDM-CAN Datalogger-to-CANbus Interface FIGURE 2-3. SDM-CAN Isolation disabled 2.3 Connection to the Datalogger and Power Supply To allow communication between the SDM-CAN and a datalogger, firstly connect it to the datalogger’s SDM port, and then connect to a 12V power supply. Both the datalogger and the SDM-CAN 12V power supply must share a common ground. The SDM port is provided in different ways on different dataloggers: CR10X and CR23X – use the C1, C2 and C3 control ports.
SDM-CAN Datalogger-to-CANbus Interface the tip of a small flat blade screw driver (3mm width) into the rectangular hole above the circular terminal hole. Push in the blade of the screwdriver until the spring is released and the terminal opens. Insert the pre-stripped wire and then remove the screwdriver. See FIGURE 2-4. If space is limited, as when the unit is mounted in an enclosure etc., the screwdriver can be inserted into the front of the terminal block to push open the spring, as shown in FIGURE 2-5.
SDM-CAN Datalogger-to-CANbus Interface An additional I/O terminal is provided on the SDM-CAN for use with dataloggers which support interrupt driven logging events. This might typically be used to enable the rapid capture of time critical CAN data, where the I/O port can be used to indicate to the datalogger that data has been captured and is available for immediate collection (see below). In most applications this function will not be used and the terminal need not be connected.
SDM-CAN Datalogger-to-CANbus Interface TABLE 2-3. CIA CAN Connector Pin Connections Pin Function 1 Reserved, NOT INTERNALLY CONNECTED. 2 CAN Low. 3 CAN Ground. 4 Reserved, NOT INTERNALLY CONNECTED. 5 CAN Shield. 6 CAN Ground. 7 CAN High. 8 Reserved, NOT INTERNALLY CONNECTED. 9 CAN +5volts. Input or output (see text).
SDM-CAN Datalogger-to-CANbus Interface 3. Programming CR10X, CR7 and CR23X Dataloggers to use the SDM-CAN This section describes the programming methods used for the above dataloggers to configure and use the SDM-CAN Interface. This section also covers general principles and techniques which are relevant to the other dataloggers. 3.1 General Principles The SDM-CAN interface is controlled by instructions that the user enters in the datalogger program.
SDM-CAN Datalogger-to-CANbus Interface CAN errors detected and to also determine the general status of the SDM-CAN interface. 3.2 System Limitations The SDM-CAN interface, in combination with a datalogger, has some limitations of which you need to be aware: 1) Memory Allocation and P118 Firstly, as discussed above, when the datalogger compiles a program with P118 in it, it sends commands to the SDM-CAN instructing it what to do at run time.
SDM-CAN Datalogger-to-CANbus Interface Data stored in packets on the CAN-Bus can be encoded in a number of different ways. The SDM-CAN itself can cater for many different types of data, but there are some limitations imposed by the way in which the data is stored in the datalogger. The prime limitation is that data read into the datalogger is first converted into a 4 byte floating point format which can only resolve, at most, 23 bits, or roughly 7 digits, of the decimal equivalent of any number stored.
SDM-CAN Datalogger-to-CANbus Interface description of the data types, entry of the instruction and how to index (‘--’) parameters. In some previous versions of datalogger operating systems, Instruction 118 was used for the now obsolete OBDII interface. Older datalogger manuals and Edlog help systems may still refer to this instruction. Please make sure you are using a version of the operating system that supports P118 and refer to a more recent datalogger manual or Edlog help system.
SDM-CAN Datalogger-to-CANbus Interface range of baud rates. However, be sure to check that these are correct for your specific network before using them. The parameters are entered as integer numbers which define various times that control when the binary data is sampled by the CAN hardware. The following discussion and nomenclature is common to the set-up of most CAN controller chips.
SDM-CAN Datalogger-to-CANbus Interface The relationship between these times is summarized by: tbit=tq+tTSEG1+tTSEG2 t TSEG1 (in seconds) is set using the scaling factor TSEG1 (parameter 03), the value of which is calculated using the following equation: TSEG1 = tTSEG1 / tq tTSEG2 is set using scaling factor TSEG2 (parameter 04) the value of which is calculated using: TSEG2 = tTSEG2 / tq When determining the settings of these parameters it is important to ensure that the size and total number of tq exactly
SDM-CAN Datalogger-to-CANbus Interface special meaning of the ID; each packet is only referenced by the full ID. The CAN 2.0A standard uses an ID with 11 bits, while CAN 2.0B uses 29 bits. When entering IDs into Instruction P118, three parameters are used. This is because the ID size, in number of bits, is too large to be encoded into a single parameter. The first ID parameter (parameter 05) sets bits 0..10, entered as a number between 0 and 2047.
SDM-CAN Datalogger-to-CANbus Interface For convenience the start bit can be referenced from either end of the frame (see parameter 09 below), but this does not change the direction in which data is encoded or decoded. Within a byte the MSBit is always first (on the left). Where the number-of-values parameter (parameter 11) is greater than one, the same function is applied to successive sections of the data frame, moving towards the ‘left’ of the frame.
SDM-CAN Datalogger-to-CANbus Interface values previously written into the memory buffer. This allows complex bit patterns to be defined, sometimes changing only as little as one bit at a time. Parameter Value Data type 13 Unsigned integer, most significant byte 1st. 14 Unsigned integer, least significant byte 1st. 15 Signed integer, most significant byte 1st. 16 Signed integer, least significant byte 1st. 17 4 byte IEEE floating point number, most significant byte 1st.
SDM-CAN Datalogger-to-CANbus Interface 3.3.5.5 Set-up previously built data frame as a Remote Frame Response (type 26): When parameter 08 is set to 26, P118 will configure the SDM-CAN to use a previously ‘built’ data frame as remote frame response for packets of the specified ID. The length and start positions are specified as for data type 25. 3.3.5.
SDM-CAN Datalogger-to-CANbus Interface 1 Bus-On; the SDM-CAN is involved in bus activities. One of the error counters is equal to or greater than 96. 2 Bus-Off; the SDM-CAN is not involved in bus activities. All of the error counters are less than 96. 3 Bus-Off; the SDM-CAN is not involved in bus activities. One of the error counters is equal to or greater than 96. See data type 28 above for details of the error counters and how to reset them. 3.3.5.
SDM-CAN Datalogger-to-CANbus Interface Switch ‘d’: 37 Currently unused 8 Set low power standby mode. The SDM-CAN cannot wake from this state as a result of CAN-Bus activity. Setting this switch to any other value will bring the SDMCAN out of standby. 9 Leave this switch setting unchanged 0 Listen only mode, no CAN transmission or acknowledgement to a correctly received CAN frame is possible. The SDM-CAN runs in ‘Error Passive’ mode (Default).
SDM-CAN Datalogger-to-CANbus Interface NOTE Please refer to the CAN standards and your own network documentation for a more detailed explanation of the switch ‘d’ modes. It is important to choose the correct setting when the SDM-CAN is required to transmit data. Also remember to check the jumper settings inside the SDM-CAN if enabling transmission, as the default setting is for transmission to be disabled in hardware. 3.3.5.
SDM-CAN Datalogger-to-CANbus Interface NOTE For some data types this parameter will be overridden by a fixed number of bits required by the data type; even so the interrupt setting can still be set. For integer values, the longest integer you can read or send from one datalogger input location is 16 bits as a result of limitations within the datalogger (see Section 3.2, System Limitations, above for an explanation and work-arounds. 3.3.
SDM-CAN Datalogger-to-CANbus Interface except those where the datalogger can be made the master (i.e. where it requests data from the remote devices when its needs the data). In other applications one has to cater for the possibility that data might not be available from the CAN network when the datalogger clock causes the datalogger to run its program.
SDM-CAN Datalogger-to-CANbus Interface following the end of one interrupt before the SDM-CAN will raise the port for another interrupt. This could be a limitation in high speed data capture applications, hence the need for switch 2. When switch 2 is set, the SDM-CAN responds immediately to data receipt and raises the port as soon as data has been received, filtered and processed.
SDM-CAN Datalogger-to-CANbus Interface Each buffer can be configured as a standard ring buffer with no trigger or filter associated with it. The buffer can also be set to start to capture data when a predefined trigger pattern is encountered within the CAN data, or it can filter and buffer only the CAN frames that have some part of the data that fits a pattern. To configure a filter or trigger two masks are used.
SDM-CAN Datalogger-to-CANbus Interface b) If (parameter 9) is one, the number of bits (parameter 10) is set to 8 with the index (--) NOT SET and number of bytes (parameter 11) is set to zero then one CAN frame will be transferred from the buffer to the working buffer ready for normal data collection using Data Types 1-6. Also the number of CAN frames stored in the buffer will be stored in a logger location specified by this instruction.
SDM-CAN Datalogger-to-CANbus Interface 1: SDM-CAN (P118) 1: 0 SDM Address 2: 4 Time Quanta 3: 5 Tseg1 4: 2 Tseg2 5: 1024 ID Bits 0..10 (-- for 11-bit CAN ID) 6: 7680 ID Bits 11..23 7: 12 ID Bits 24..28 8: 2 Rx, unsigned int, LSB 1st 9: 33 Start Bit No. 10: 16 No. of Bits 11: 1 No. of Values 12: 1 Loc [ Eng_Spd ] 13: 0.125 Mult 14: 0.0 Offset *Table 2 Program 02: 0.
SDM-CAN Datalogger-to-CANbus Interface ;Send switch settings to SDM-CAN 7: SDM-CAN (P118) 1: 0 SDM Address 2: 2 Time Quanta 3: 5 Tseg1 4: 2 Tseg2 5: 1 ID Bits 0..10 6: 0 ID Bits 11..23 7: 0 ID Bits 24..28 8: 32 Set switches 9: 00 Start Bit No. 10: 00 No. of Bits 11: 00 No. of Values 12: 3 Loc [ Switches ] 13: 1.0 Mult 14: 0.
SDM-CAN Datalogger-to-CANbus Interface 13: 1.0 14: 0.0 Mult Offset *Table 2 Program 02: 0.0000 Execution Interval (seconds) *Table 3 Subroutines End Program The default setting for the SDM-CAN internal software switches is 0. The switches must be set by using the data type 32 parameter to enable data transmission. Also remember to check the jumper settings inside the SDM-CAN if enabling transmission, as the default setting is for transmission to be disabled in hardware. NOTE 3.5.
SDM-CAN Datalogger-to-CANbus Interface ;{CR23X} ; *Table 1 Program 01: 1 Execution Interval (seconds) ;Set flag 1 high to set SDM-CAN internal software switches 1: If Flag/Port (P91) 1: 11 Do if Flag 1 is High 2: 30 Then Do ;Load input location with value for switches 2: Z=F (P30) 1: 10 F 2: 0 Exponent of 10 3: 3 Z Loc [ Switches ] ;Send switch settings to SDM-CAN 3: SDM-CAN (P118) 1: 0 SDM Address 2: 2 Time Quanta 3: 5 Tseg1 4: 2 Tseg2 5: 1 ID Bits 0..10 6: 0 ID Bits 11..23 7: 0 ID Bits 24..
SDM-CAN Datalogger-to-CANbus Interface 7: 8: 9: 10: 11: 12: 13: 14: 0 1 1 16 1 10 1.0 0.0 ID Bits 24..28 Rx, unsigned int, MSB 1st Start Bit No. -- No. of Bits No. of Values Loc [ RxTC_1 ] Mult Offset ;end of interrupt subroutine 3: End (P95) End Program 3.5.5 Using the Group Trigger The SDM-Group Trigger controls SDM devices that support the Group Trigger protocol, including the SDM-CAN.
SDM-CAN Datalogger-to-CANbus Interface ;Retrieve Data from CAN network B 3: SDM-CAN (P118) 1: 01 SDM Address 2: 4 Time Quanta 3: 5 Tseg1 4: 2 Tseg2 5: 1024 ID Bits 0..10 (-- for 11-bit CAN ID) 6: 7680 ID Bits 11..23 7: 12 ID Bits 24..28 8: 2 Rx, unsigned int, LSB 1st 9: 33 Start Bit No. 10: 16 No. of Bits 11: 1 No. of Values 12: 2 Loc [ Eng_1 ] 13: 0.125 Mult 14: 0.0 Offset ;Retrieve Data from CAN network B 8: SDM-CAN (P118) 1: 01 SDM Address 2: 4 Time Quanta 3: 5 Tseg1 4: 2 Tseg2 5: 768 ID Bits 0..
SDM-CAN Datalogger-to-CANbus Interface Section 3, Programming CR10X, CR7 and CR23X Dataloggers to use the SDM-CAN. To avoid duplication this section of the manual simply references the relevant paragraphs in that section. For this reason you are advised to read section three in its entirety to gain a full understanding of all the general principles and parameter settings. Currently neither the CR5000, CR9000X nor CR9000 support interrupt driven events as described above.
SDM-CAN Datalogger-to-CANbus Interface require an update to your CRBASIC editor to get the full help screens. Contact Campbell Scientific if you need advice about upgrading your operating system. The CANBUS instruction takes the form: CANBUS(CANDATA(),ADDRESS,TIMEQUANTA,TSEG1,TSEG2,ID, DATATYPE,STARTBIT,NUMBITS,NUMVALS,MULT,OFFSET) where: CANDATA is a variable or array which either holds data to be transmitted or will hold data that is to be read from the CAN-Bus.
SDM-CAN Datalogger-to-CANbus Interface Const CMULT1 = 0.
SDM-CAN Datalogger-to-CANbus Interface '\\\\\\\\\\\\\\\\\\\\\\\\\\\ PROGRAM /////////////////////////// BeginProg 'Program begins here 'MainSequence Scan(PERIOD,P_UNITS,0,0) 'Scan once every 1 Secs, non-burst '__________________________ Temp Blocks __________________________ ModuleTemp(TRef(),1,5,100) TCSE(TBlk1(),TREP1,TRNG1,5,1,TTYPE1,TRef(1), TSETL1,TINT1,TMULT1,TOSET1) '__________________________ CAN Blocks __________________________ 'When Flag 1 is high set SDM-CAN switches to transmit mode If Flag(1)
SDM-CAN Datalogger-to-CANbus Interface '\\\\\\\\\\\\\\\\\\ ALIASES & OTHER VARIABLES ////////////////// Alias CANBlk1(1) = Accel_Pedal 'Assign an alias name to CANBlk1(1) '\\\\\\\\\\\\\\\\\\\\\\\\\\\ PROGRAM /////////////////////////// BeginProg 'Program begins here 'MainSequence Scan(PERIOD,P_UNITS,0,0) 'Scan once every 1 Secs, non-burst '__________________________ CAN Blocks __________________________ 'Read status of digital I/O port, return value to NewData variable ReadIO(NewData,7,&B1) 'When digital I
SDM-CAN Datalogger-to-CANbus Interface 8 CTS input. 9 RI input. To connect the SDM-CAN to most computers use a NULL Modem cable. When you try to communicate with the SDM-CAN, first send at least three ‘Carriage Returns’ so the SDM-CAN can recognize the baud rate at which you are communicating. As soon as your baud rate has been detected, the SDMCAN will return the prompt ‘CAN>’ to your terminal window.
SDM-CAN Datalogger-to-CANbus Interface The CANBUS is scanned for the following baud rates: 20K, 50K, 125K, 250K, 500K, 800K and 1 Megabaud. As soon as the baud rate is found, the bus parameters TQUANTA, TESG1, TSEG2 and frames / n*50msec are reported to the user. The SDM-CAN will then be set to, and stay at, this baud rate until the changed by the datalogger following a re-compilation of the program by the user, or by a datalogger SDM communications error which will force the SDM-CAN to be reset.
SDM-CAN Datalogger-to-CANbus Interface or by a datalogger communications error, which will force the SDM-CAN to be reset. If parameters are omitted, the default setting is 1 Megabaud with the following parameters: TQUANTA=1, TSEG1=5 and TSEG2=2. Because any communication errors cause a default back to the datalogger set baud rate, it is not recommended that this command is used for anything other than CANBUS diagnostic purposes. STAT – Takes no parameters.
SDM-CAN Datalogger-to-CANbus Interface For downloading software you will need the following: • Device Configuration Utility (DevConfig), which is bundled with PC400 and LoggerNet datalogger support software. It is also available at no charge from www.campbellsci.com/downloads.
Appendix A. Principles of Operation A.1 Data Collection The SDM-CAN operation is based on a number of sequential buffers. The hardware has a dedicated CAN controller chip connected to a microprocessor which analyses and processes the raw CAN data and then transmits it to the datalogger. When the CAN-Bus controller receives a good frame first of all it uses its internal hardware to filter out the frames of no interest to the user.
Appendix A. Principles of Operation A.2 Frame Transmission When the datalogger program is first run it will set-up the SDM-CAN BINs and buffers. If the program has some P118 instructions that transmit to the CAN-Bus, then some of the Buffers will be set-up for transmission. When an instruction indicates that a transmission should take place, the datalogger first sends a BIN number. This number tells the SDM-CAN which BIN to use and, from the compile-time set up, what operation is required.
Appendix B. A Summary of Data Types A summary table of the data types is given below for quick reference.
Appendix B. A Summary of Data Types Data Type Description 29 Read SDM-CAN status Status Description 0000 The SDM-CAN has bus activities; error counters < 96. 0001 The SDM-CAN has bus activities; at least one error counter is >= 96. 0002 The SDM-CAN is not involved in bus activities; error counters < 96. 0003 The SDM-CAN is not involved in bus activities; at least one error counter >=96. 30 Read SDM-CAN operating system and version number 31 Send Remote Frame Request.
Appendix C. Application of the SDMCAN on Networks Complying with the J1939 SAE Standards This Appendix describes the use of the SDM-CAN in applications where the CAN network complies to the J1939 standard, which is common in truck, bus and marine applications in the USA. This appendix is not intended to act as a full reference to those standards, but to simply describe the coding of the ID parameter and to give examples of how to decode some of the common, defined J1939 data packets. C.
Appendix C. Application of the SDM-CAN on Networks Complying with the J1939 SAE Standards NOTE Details of identifier field values can be found in the SAE J1939 standard. C.3 J1939 Data Frame Format The Data Frame consists of 8 bytes with byte one at the left side of the frame and byte eight at the right side. Within each byte, bit 8, the most significant bit is at the left side of the byte. NOTE Multi-byte values are conventionally displayed with the least significant byte first.
Appendix C. Application of the SDM-CAN on Networks Complying with the J1939 SAE Standards TABLE C-4.
Appendix C. Application of the SDM-CAN on Networks Complying with the J1939 SAE Standards NOTE Due to current system constraints the ID parameter must be entered directly into the CanBus instruction. C.5 Retrieving J1939 Accelerator Pedal Position Data using a CR23X/CR10X (Bus Speed 250k Baud) C.5.1 Encoding the Identifier Field Values The following example shows how to encode the identifier field values into the format for the CR23X/CR10X ID parameter.
Appendix C. Application of the SDM-CAN on Networks Complying with the J1939 SAE Standards C.5.2 Finding the Start Bit The byte number of the Accelerator pedal position value is 2 TABLE C-7. Accelerator Pedal Position Value Byte Number 1 2 3 4 5 6 7 8 87654321 87654321 87654321 87654321 87654321 87654321 87654321 87654321 The start bit for this value is 49, as it is the least significant bit of the data value within the data frame that this parameter refers to.
Appendix C.
Appendix D. Examples of CAN Data Frames and Data Encoding and Decoding This Appendix gives examples of typical CAN data frames with worked examples of how to encode or decode such data using the SDM-CAN. Bits are Transmitted (Txed) or Received (Rxed) starting from the left of the data frame.
Appendix D. Examples of CAN Data Frames and Data Encoding and Decoding Examples of values within a data-frame 16bit data frame with a one value 16bit unsigned integer LSByte first Rxed Bit order within bytes 87654321 Rxed Byte order Byte 1 Byte 2 Values A Bit order within values 8 Value byte order LSByte Start bit (parameter 09:) RH ref 16 9 8 1 Start bit (parameter 09:) LH ref 1 8 9 16 Start bit (parameter 09:) Right Hand reference.
Appendix D. Examples of CAN Data Frames and Data Encoding and Decoding 32bit data frame with two 16bit unsigned integer values LSByte first.
Appendix D. Examples of CAN Data Frames and Data Encoding and Decoding 24bit data frame with two 12bit unsigned integer values LSByte first Rxed Bit order within bytes 87654321 87654321 87654321 Byte 1 Byte 2 Byte 3 Rxed Byte order Values B A Bit order within values 8 Value byte order LSByte LSNib Start bit (parameter 09:) RH ref 24 17 16 13 12 9 8 1 Start bit (parameter 09:) LH ref 1 8 9 12 13 16 17 24 1 Start bit (parameter 09:) Right Hand reference.
Appendix D. Examples of CAN Data Frames and Data Encoding and Decoding 16bit data frame with one 12bit signed integer value LSByte first Rxed Bit order within bytes Rxed Byte order 87654321 87654321 Byte 1 Byte 2 Values A Bit order within values 4 Value byte order LSNib Start bit (parameter 09:) RH ref 16 13 12 9 8 1 Start bit (parameter 09:) LH ref 1 4 5 8 9 16 1 S A 12 5 MSByte S = sign bit which is the MSBit of the value, bit 12.
Appendix D.
Appendix D. Examples of CAN Data Frames and Data Encoding and Decoding 16bit data frame with one 16bit unsigned integer value MSByte first Rxed Bit order within bytes 87654321 Rxed Byte order 87654321 Byte 1 Byte 2 Values A Bit order within values 16 Value byte order MSByte Start bit (parameter 09:) RH ref 16 9 8 1 Start bit (parameter 09:) LH ref 1 8 9 16 9 8 1 LSByte Start bit (parameter 09:) Right Hand reference.
Appendix D.
Appendix D.
Appendix D. Examples of CAN Data Frames and Data Encoding and Decoding 16bit data frame with one 12bit unsigned integer value MSByte first Rxed Bit order within bytes Rxed Byte order Values A Bit order within values 12 Value byte order 87654321 Byte 1 Byte 2 A 9 8 MSNib 1 LSByte Start bit (parameter 09:) RH ref 16 13 12 9 8 1 Start bit (parameter 09:) LH ref 1 4 5 8 9 16 Start bit (parameter 09:) Right Hand reference.
Appendix D.
Appendix D.
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