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LV built-app talk to CVI/VisualStudio exe: how?


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DLL functions or shared variables?  Or something else?

I have a Labview 2014-64 executable (or I can build a DLL) that runs one piece of equipment, the X-ray.  The other engineer has a large CVI Labwindows 2015 + MS Visual Studio 2012 (C++) executable that runs everything else.  I want the Labview code to be a slave of the CVI code, accepting commands to turn X-ray On or Off, reporting failures, and the like.  Translating the X-ray code into C++ would be possible in principle, but not fun.

Shared variables look easy, but I'm kinda scared of them.  I would define all the shared variables in my LV code, since I'm more familiar with LV, then use them in both.  There's a thread in here called "Shared Variable Woes" so maybe I should be scared.  In the alternative, I tried building a proof-of-concept DLL in Labview, and calling its functions in CVI/C++, and it works, but it's kinda clunky.  (I'm attaching it below in case you want to play, or advise.)

Your advice would be appreciated.

XrayDLL.zip

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Raw TCP.

Make your application respond to SCPI commands and the other engineer can treat it like any other instrument. Can even be over a network (remote). It's a simple method which is programming language independent and can be added to existing applications without much problem. Also has no additional installation or distribution requirements.

Edited by ShaunR
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