Modbus TCP Explicit Messaging Function Codes
Original instructions
About us
Overview
Every Modbus TCP explicit message performs a function. Each function is associated with a code (or number). You will need to identify the explicit messaging function by its name, decimal number, or hexadecimal number.
You can execute Modbus TCP explicit messages using either a Control Expert MBP_MSTR function block or the Control Expert Ethernet Configuration Tool’s Modbus Explicit Message Window.
NOTE: Configuration edits made to an Ethernet communication module from the Control Expert Ethernet Configuration Tool are not saved to the operating parameters stored in the CPU and, therefore, are not sent by the CPU to the module on startup.
Services
The function codes supported by Control Expert include the following standard explicit messaging functions:
Function Code
Description
Available in...
Hex
Dec
MBP_MSTR block
Control Expert GUI
1
1
Write data
X
X
2
2
Read data
X
X
3
3
Get local statistics
X
X
4
4
Clear local statistics
X
X
7
7
Get remote statistics
X
X
8
8
Clear remote statistics
X
X
A
10
Reset module
X
X
17
23
Read / write data
X
X
FFF0
65520
Enable / disable HTTP and FTP/TFTP services
X
-
"X" = the service is available.
"—" = the service is not available.