Chapter 3: Modbus Rtu Functions And Addressing Modes; Modbus Rtu Function Codes; Modbus Function Codes Supported - Automation Direct T1K-MODBUS-M User Manual

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MODBUS RTU Functions and Addressing Modes

MODBUS RTU Function Codes

MODBUS Function
Codes Supported
The following MODBUS RTU functions are supported by the T1K–MODBUS base
controller.
MODBUS RTU
Function Code
01 Read Output Table
02 Read Input Table
03 Read Holding Registers (when addressing
mode is 584/984, this function is used to ac-
cess analog output registers)
04 Read Input Registers (when addressing mode
is 584/984, this function is used to access
analog input registers)
05 Force Single Output
06 Preset Single Registers
07 Read Exception Status
08 Loop back / Maintenance
09 – 14 –
15 Force Multiple Outputs
16 Preset Multiple Registers
17 Report Device Type
18 – 64 –
65 not supported
66 not supported
68–70 not supported
72 not supported
73 – 127 –
Function