Is RT supported?

[Adan Ascencio]

We're working on an application with the JSONtext library and a PXIe-8861, whenever we attempts to call a PPL that includes an element from JSONtext library, it cannot deploy (Error 0x2A: Generic Error). However, these VIs with elements from this library works fine in non-RT LabVIEW and just running the VI from the library on RT.

This was our process:
 

Build a new Packaged Library with the Process File 01.vi on it (file attached). 

Open a new project, add your Real Time Target and add the Packaged Library

 

Create a VI calling the Process File 01.vi

 

Connect to the real-time target, deploy and try to run the last VI we created.

 

This behavior happened with 2021, with 2022 it deploys with error without showing any specific one and lost connection to target after this.

Process File 01.vi

[Jim Kring]

I think this might be a LabVIEW bug related to PPLs and Malleable VIs.  Maybe @Jamespowell80 knows.

[sekel]

I was able to work around this issue. It seems the problem is using a malleable VI (VIM) that has a class input (LVClass Serializer). If you right-click on the malleable VIMs after you wire them on your block diagram and convert them to a standard VI, you should have success deploying the PPL to the real-time target. 

Note: This issue has been reproduced with other malleable VIMs (not in the JSON add-on) that have a LV class input ("Search Unsorted 1D Array.vim" for example). In all instances so far converting to a standard VI has yielded success.

Great call @Jim Kring on looking at the malleable VIs.

[Jett]

sekel do you have any more insight you can provide on this? I am trying to use the "From json text" VI on the processor side of a cRIO. The code deploys fine, but when I hand this block a json string it just spits out default data. However if the processor is running by itself, and no other VIs on the computer are running, it seems to work fine. But once I run a VI on the PC that is meant to send the json string down to the processor, the processor can no longer parse the string. I tried converting the "from json text" block to a Standard VI, but that seemed to have the same behavior. Images attached to show the behavior I am talking about.