315-4PN33

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).
If the slave announces an error, the function code is send back with
an "ORed" 80h.
Overview
Respond of the slave
VIPA System 300SDeployment PtP communication
Modbus - Function codes
HB140 | CPU | 315-4PN33 | GB | 14-43 100