A description of the function codes follows below.
With the following Modbus function codes a Modbus master can access a Modbus slave:
With the following Modbus function codes a Modbus master can access a Modbus slave.
The description always takes place from the point of view of the master:
Code
Command
Description
01h
Read n bits
Read n bits of master output area 0x
02h
Read n bits
Read n bits of master input area 1x
03h
Read n words
Read n words of master output area 4x
04h
Read n words
Read n words master input area 3x
05h
Write 1 bit
Write 1 bit to master output area 0x
06h
Write 1 word
Write 1 word to master output area 4x
0Fh
Write n bits
Write n bits to master output area 0x
10h
Write n words
Write n words to master output area 4x
Point of View of "Input" and "Output" data
The description always takes place from the point of view of the master. Here data, which
were sent from master to slave, up to their target are designated as "output" data (OUT)
and contrary slave data received by the master were designated as "input" data (IN).
Overview
VIPA System SLIO
Serial communication protocols
Deployment - Modbus > Modbus - Function codes
HB300 | CP | 040-1CA00 | en | 18-28
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