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Issue implementing a modbus IO server on RT target

I am trying to implement a modbus I/O server using modbus ethernet onto a RT target (cRIO 9045).  I am using LabVIEW 2023 Q3. 


When the modbus I/O server is deployed onto the RT target, the NI Distributed Manager shows the library (MP3300) under the cRIO in 'Networked Items', however there are no variables listed under that library.  When I attempt to read the shared variables, both coils, they do not read properly.  I have confirmed that 000001 is False and 000002 is True, for testing. Image attached.


When I move the I/O server and to the host PC, the NI Distributed Manager shows the library under the desktop in 'Networked Items' and this time there are the two shared variables listed, where I can confirm the state of both coils.  Similarly, my simple confirms the variables are reading properly.  Image attached.


I have added almost all of the available software to the cRIO thinking I have missed an important item, however I have not been able to get this to work.


Is there something I am missing here?  My next step will revert to 2022 and see if the same issue persists.



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Did you ever get this fixed? I am having the same problem. I've done this before and it worked, so I'm thinking it is simple.

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