WAGO 750-872/020-000 Manual page 157

These functions allow digital or analog input and output data, and internal
variables to be set or directly read out of the fieldbus node.
FC1:
FC2:
FC3:
FC4:
FC5:
FC6:
FC 11:
FC 15:
FC 16:
FC 22:
FC 23:
Tab. 4-3: List of the MODBUS Functions in the Fieldbus Controller
To execute a desired function, specify the respective function code and the
address of the selected input or output data.
Attention
The examples listed use the hexadecimal system (i.e.: 0x000) as their
numerical format. Addressing begins with 0.
The format and beginning of the addressing may vary according to the
software and the control system. All addresses then need to be converted
accordingly.
WAGO-I/O-SYSTEM 750
ETHERNET TCP/IP
Function code
Function
hexadec.
0x01 Read Coils
0x02 Read Input
Discretes
0x03 Read Multiple
Registers
0x04 Read Input
Registers
0x05 Write Coil
0x06 Write Single
Register
0x0B Get Comm
Event
Counters
0x0F Force Multiple
Coils
0x0010 Write Multiple
Registers
0x0016 Mask Write
Register
0x0017 Read/Write
Registers
Fieldbus Communication
Access method and
description
Reading of several R: Process image, PFC variables
single input bits
Reading of several R: Process image, PFC variables
input bits
Reading of several R: Process image, PFC variables,
input registers internal variables, NOVRAM
Reading of several R: Process image, PFC variables,
input registers internal variables, NOVRAM
Writing of an W: Process image, PFC variables
individual output
bit
Writing of an W: Process image, PFC variables,
individual output internal variables, NOVRAM
register
Communication R: None
event counter
Writing of several W: Process image, PFC variables
output bits
Writing of several W: Process image, PFC variables,
output registers internal variables, NOVRAM
W: Process image, PFC variables,
NOVRAM
Reading and R/W: Process image, PFC variables,
writing of several NOVRAM
output registers
MODBUS Functions
Access to resources
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