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2 Protocol description
2.5 Structure of the data blocks
All data blocks have the same structure:
Data structure
Each data block contains four fields:
Slave address device address of a specific slave
Function code function selection (read, write words)
Data field contains the following information:
- word address
- number of words
- word value(s)
Checksum detection of transmission errors
Slave
address
Function
code
Data field Checksum
CRC16
1 byte 1 byte x byte 2 bytes