Need help with Call By Reference on cRIO-9012

Question

I have a RT application running on a cRIO-9012 in which I am attempting to establish references to a variable number of clones of the PID Autotuning (Temperature).vi, and then passing these references to a FOR loop in which I am opening each clone with a Call By Reference node to perform the PID.  Essentially, I am trying to make the PID Autotuning (Temperature).vi accept an array of process variables, similar to the behaviour that some of the simpler PID VIs provide out-of-the-box. 
The code I am using to obtain the references is here:
...and the code within the control loop where I am trying to do the processing is here:
The problem I am encountering, according to the Highlight Execution tool, is that all inputs to the Call By Reference node are present and reach the node, but all processing stops at this point on the first iteration and the cRIO hangs.  I cannot stop the SubVI or the RT parent VI without performing a software restart on the target.
I don't know if I am using the Call By Reference node or Open VI Reference functions incorrectly, or if there is a problem with the VI being part of a library, or if something else is wrong.  Any help would be appreciated.
Sean

Answer 1

I'm not sure this is your issue, but I think there's a conflict between opening a bunch of rereferences, and then setting the asynchronous call pool size for one of them.You don't need asynchronous execution here, you just need reentrant parallel execution (you may not even need the parallel part; your current code, if it worked, would execute sequentially, and the PID calculation is just math so should be quick and may not benefit from parallel execution). You do need reentrant execution to maintain separate data spaces.
Try opening the references with the 0x08 (Prepare for Reentrant Run) flag instead. Remove the Populate Asynchronous Call Pool. If this works, you can run in parallel by enabling For loop parallelism - but you might find that's actually slower, especially on a cRIO.