Omron J7 series, User Manual

Page: 114 / 177

100
Message Communications Basic Format
Chapter 7-3
Error Check
The CRC-16 check code is the remainder (16 bits) when all of the message
blocks from the Slave address to the final communications data are
connected in series, as shown in the following diagram, and this data is
divided by a fixed 17-digit binary number (1 1000 0000 0000 0101).
8 bits
Slave address
Function code
Start of communications data
End of communications data
The LSB of the Slave address is handled as the MSB in CRC-16 calculation.