• Not Answered

Changing Registers Sequence ModBus

Hi there!

DeltaV 13.3.1

I'm using a device having a non-standard Modbus register sequence, I need to get Float Value. Assume there is temperature 61.2°С It means registers I must receive are 250 204 116 66, but the used device has register sequence such as 116 66 250 204, so I have to change the register sequence. Currently I get incorrect value such as -4.234+012 or similar. After describing problem, I have two ways for solution.

First, I can change the sequence using custom FB in ControlStudio and receive two16bit integer instead of float, example at the picture below. This way is easier for me, but I want to find more flexible way to solve the problem without using additional FB.

Second, I can reconfigure Standard SI Module to programmable SI Module and use SampleCustomProtocol ModBus by Mynah  , I hope someone used it somewhen, but  I have a problem when I full textbox up in the Special Data Tab the necessary value as sown at the picture below and download ProgSI Module, Registers don't change sequence. Maybe someone can help me to find a way to solve the problem.

If someone knows others ways to change registers sequence, I'll be glad to read them.

Thanks!