Datasheet
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Save word length
1
0x02
Save the data word length (2 words)
Save Data1
1
0x01
Save the data (address: 10)
Save Data2
1
0x02
Save the data (address: 11)
CRC code
2
C092
Host calculated CRC code, low byte first(C
addresses are not included in the CRC calculation)
Sensor response message format returned:
Slave response
Byte count
Transmitting information
Remarks
Function Code
1
0x10
Write Multiple Registers
Starting address
1
0x10
Starting address saved
Save the data length
1
0x10
Save the data length sensor
CRC code
2
0x10
Sensors calculate the return CRC code, low byte first
◎CRC checksum
Host or sensors available checksum discriminate receiving information is correct. As electronic
noise or some other interference during the transmission of information is sometimes an error occurs,
the error check code (CRC) can test the host or sensor information in the communication data
transfer process is wrong, wrong data can give (either sending or receiving), thus increasing the
safety and efficiency of the system.
CRC I
2
C-Mod Bus communication protocol (cyclic redundancy code) contains two bytes, or
16-bit binary number. CRC code by the sending device (host) calculations, send the information
placed in the rear frame, I
2
C address is not included in the CRC calculation. Whether sending or
receiving CRC are by the low byte first, high byte format for transmission in the post. Receiving
information on the device (sensor) to recalculate the information received CRC, the CRC is
calculated by comparing the received query, and if they do not match, then the error. Users need
special attention, reading sensor command without adding the CRC; writing sensors must be added
the CRC; and all the return data are CRC.
◎CRC code calculation method
1. Preset a 16-bit register hexadecimal FFFF (including 1); said this register for the CRC
register;
2. The low (first byte frames both communications and information) first 8-bit binary data
with 16-bit CRC register eight or different, the results put in CRC register;
3. The contents of the CRC register right one (towards low) with zeros to fill the highest
position, and check out bit right after;
4. If the bit is 0 out: Repeat steps (the right one again) 3; If the bit is shifted 1: CRC register
with the polynomial A001 (1010 0000 0000 0001) XOR;
5. Repeat steps 3 and 4 until the right eight times, so that the entire eight were processed all
the data;
6. Repeat steps 2 through 5, the communication of information to the next frame byte
processing;
7. The communication message frame after all the bytes calculated according to the above
steps completed, the high and low byte of the resulting 16-bit CRC register exchange;