Modbus Function Codes; Process Data (Cyclic Communication) - Baumuller b maXX 5000 Series Instruction Handbook Manual

7.2

Modbus function codes

The Modbus/TCP add on module supports word access (16 bits) to Modbus register, on-
ly.
The following function codes are supported:
Function code
FC3
FC4
FC6
FC16
FC23
7.3

Process data (cyclic communication)

The cyclic communication can be configured by Modbus register 000 to 599. The com-
munication exchanges defined parameters (objects) between the Modubus/TCP client
and the b maXX 5000 Modubus/TCP server.The exchanged parameters are named pro-
cess data objects (PDO).
Modbus register Meaning
000 – 001
002 – 065
066 – 099
100 – 101
102 – 165
166 – 199
200 – 201
202
203
204
205 – 209
210 – 337
338 – 409
410 – 537
538 – 599
Meaning
Read multiple register (WORD access)
Read input register (WORD access)
Write single register (WORD access)
Write multiple register (WORD access)
Read/Write multiple register
Modbus status word
Actual process data (Actual PDO)
Reserved
Modbus control word
Set process data (Set PDO)
Reserved
Error code
Cycle time of the process data communication
Actual value watchdog time
Set value watchdog time
Reserved
Actual process data mapping
Reserved
Set process data mapping
Reserved
Instruction handbook b maXX 5000 add-on module MOD
General Description
Document No.: 5.19015.01
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