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Variant type in teststand?



Case 1:

I have two steps in a sequence (both written in LabVIEW), one has a variant output the other has a variant input. Variant outputs show up as "Anything" in teststand and I have noticed that I can use a string local to pass the data from the first step to the other. This is working fine...


Case 2:

Now I am working on a sequence which works like this:

First I start a subsequence in a new thread, which has only one step. This step does continous data acquisition and running in parallel to my main sequence. The subsequence has string type parameter passed by reference (myVariantData). My plan was to use the Sequence Context input and write my variant data to the myVariantData variable periodically, so another VI in my main sequence can get data from this continuously running VI.


Its a bitter surprise that when I try doing it TS drops an error message saying that the types dont match. Which is true, but then why does it work in Case 1 when I write a variant output to a string local?


So I can't write write a variant to a string local with the seq.context/parameters/setstringval, and I dont know how to create a variant datatype in teststand, so I cant make this work right now.


What would be the right approach?





EDIT: so I am looking for a mechanism to pass data from a continously running VI to another one in teststand. I CAN use queues or notifiers or something like this so my labview VIs can communicate each other, but I am wondering if I can do it easier in TS.

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In any case I would use Queues to share data between processes running in parallel.

However, to try to answer you question, on parameters TS check types. Did you right-click on your parameter and unchecked 'Check Type' option ?

I'm not sure of the beahviour in execution...


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Yeah, unchecking the "check type" may solve this issue. Unfortunately I had to move forward and started to use queues, which are probably better anyways.

Thanks for your response.

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