User Manual

2 Protocol description
12
Response in
the event of an
error
The function code is ORed with 0x80, which means that the MSB (most
significant bit) is set to 1.
Example Data request:
Response:
Special cases The slave will not respond in the following error situations:
- the checksum (CRC16) is not correct
- the instruction from the master is incomplete or over-defined
- the number of words or bits to be read is zero
Slave
address
Function
XX OR 80h
Error code Checksum
CRC16
1 byte 1 byte 1 byte 2 bytes
01 03 40 00 00 04 CRC16
01 83 02 CRC16