Modbus TCP Explicit Messaging Function Codes

Overview

Every Modbus TCP explicit message performs a function. Each function is associated with a code (or number). You need to identify the explicit messaging function by its name, decimal number, or hexadecimal number.

You can execute Modbus TCP explicit messages using a Control Expert MBP_MSTR function block.

Services

The function codes supported by Control Expert using the MBP_MSTR function block include the following:

Function code		Sub-code		Description
Hex	Dec	Hex	Dec	Description
0x01	1	–	–	Write data
0x02	2	–	–	Read data
0x03	3	–	–	Get local statistics
0x04	4	–	–	Clear local statistics
0x07	7	–	–	Get remote statistics
0x0A	10	–	–	Reset module
0x17	23	–	–	Read/write data
0xFFF0	65520	–	–	Enable / disable FTP service