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What Modbus Function Codes are supported on the Magelis that are using Vijeo Designer Runtime?

Issue:
What Modbus Function Codes are supported on the Magelis that are using Vijeo Designer Runtime?

Product Line:
XBTG/GH/GK/GT, HMIGTO/GTU/STO/STU, Magelis iPC, Panel PC, Box PC

Environment:


Cause:


Resolution:
Below is the Table of Modbus function codes recognized by the Magelis target machine.
 
Classes   Function name Function code (hex)
Basic Read Holding registers 3
Base  Write Multiple registers  10
Regular Read Coils  01
Regular Read Discrete Inputs 02
Regular  Write Multiple Coils 0F
Regular Diagnostic 08
Supplementary services Read Input registers 04
Supplementary services Write Single Coil  05
Supplementary services  Write Single register 06
Supplementary services  Read Device Identification (only for Modbus TC/IP with target machine server) 2B

By default the target machine uses the function code 10 (FC 10) to write multiple registers.
However, some devices do not know this function code. When a device doesn’t know FC 10, the
target machine will automatically use (without any error code) FC 06. In the same way, the target
machine will use FC 05 instead of FC 0F. In addition, FC 06 and FC 05 will be used if Preferred
Frame Length is set to Minimum possible.
 
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