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Multiple concurrent LabVIEW apps sharing card resources in one cDAQ chassis

I'm looking for help, reallly a yes/no answer and/or pointers/suggestions as to the feasability of as well as how to have multiple LabVIEW apps run concurrently and share resources (cards) from a single cDAQ module.  The background is that I have an array identical of LabVIEW test systems that are used to perform testing in environmental chambers, and there are many different standardized tests that they run, ideally some (that use different resources) at the same time.  The problem is that different tests use different subsets of the cDAQ resouces, but the goal is to be able to run multiple tests/apps (for example, for multiple pieces of equipment in the environmental chamber) at the same time).  Can LabVIEW apps be structured such that they can share a module in a cDAQ chassis?  For example, if I have 20 thermocouples connected to the chassis that can all be scanned/read at the same rate (around once/second), can one app read some of them and another app read others of them virtually concurrently, perhaps by sharing a common task?

 

Any advice as to how something like this could/should be done would be appreciated.

 

Thanks.

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The common task would have to be in a single VI. You can't share modules and for some chassis, you can't share that either. You can create a single app and use shared variables that other VIs can read and get just the channels they need.
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I would also make a separate application to handle the DAQ stuff.  Depending on what you need, I would likely use a combination of TCP/IP, UDP, and shared variables to send commands, stream data, and get latest data.



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Thanks for the replies.  In keeping with the "keep it simple" mindset, I'll try some experiments using one app to make shared variables that other apps can read and see how that works.  The rate at which these apps need to read data is incredibly low (about 1 Hz), and the data itself is very small (single temperatures for a relatifvely small array of thermocouples, and a few other voltages too).  That sounds like a good way to partition responsibilities too.

 

 

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