Below list describes the meanings of exception codes:
Function Code
Meaning
01 illegal function
code
SPM33 Modbus support the function code include: 01H,
02H, 03H, 05H, and 10H.
This code means the slave device receive an illegal
function code, or the SPM33 receive the error command.
02 illegal function
code
SPM33 receive the address referenced in the data field
is an invalid address.
03 illegal function
code
The requested register number is too long.
8.2.5. Broadcast Packets
SPM33 support broadcast commands when communicating in MODBUS mode.
Do write command 0x10 for timing.
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