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DAQ acquisition hangs when panel of standalone executable is not the top panel

Dear DAQperts,

 

this seems like a beginners issue to me, but so far I couldn't fix it.

I have a CVI (2020) data acquisition routine that continuously reads and processes an analogue channel (external triggering). Once finished, it displays the processed waveform on a graph and saves it to a file.

 

The program works fine both in debug and release configuration (both in 64 bit). The program keeps running even if the panel is minimized or covered by other Windows applications. However, if I build a distribution and install it as a standalone (on the same or another computer), the acquisition runs only as long as the panel has the focus. If I switch to another task, i.e. another panel is the topmost, the DAQ software stops with a circling mouse cursor.

Any ideas what I might miss / directions I could investigate?

 

Thanks in advance,

Wolfgang

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Could it be that you initialize, start or drive the DAQ somehow from within your UI panel callback?

 

I could imagine that some of those UI callbacks somehow get still called in the background when running in the CVI IDE but won't just be suspended if the panel is not visible or the front most.

Rolf Kalbermatter
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Thanks Rolf for your suggestion.

 

Actually I have tried a version without a panel callback, using a QUIT button instead for closing the program, and in the panel configuration disallowing sizing and moving of the panel, with no change.

The whole DAQmx setup is done within the START button callback: if it is called by a COMMIT event, I do the acquisition stuff and swallow all further events (by returning 1)

 

 

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