program wont end (while loop stop control)

[MTB77]

Hi,

I have a data acquisition set up to acquire data for 100 ms (rate=10000 S/s, samples= 1000) when the PFI line on my DAQ device recieves a digital trigger. The entire code is in a while loop with a control wired to the stopping condition. The timeout on my DAQ assistant is set to -1, because I want the program to wait for the user to send the trigger signal. When I press the stop control on the front panel, the program doesn't end. I believe this is because the DAQ assistant is waiting to acquire data indefinitely because the time out is set to -1. I need the program to end when that stop control is pressed. 

Any suggestions?

Thankyou

[altenbach]

Show us your code.

[JÞB]

And of course you started with a DAQ assistant.  Go back and start with one of these http://www.ni.com/white-paper/14121/en/

Now you have a framework that does what you want and responds to the user.

[MTB77]

This isn't the exact program, but its the same problem.

Also, I have a rising trigger to start acquisition.

[crossrulz]

Put in a timeout and see what happens.  If you don't get your data, you just skip the checking of the data.  Loop until you get your stop condition.

[MTB77]

If I set a timeout and hit the stop control, the program waits for the timeout that I set and returns an error (200284).

[altenbach]

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@MTB77 wrote:

If I set a timeout and hit the stop control, the program waits for the timeout that I set and returns an error (200284).

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Is this a problem for you, or just a comment?

[MTB77]

A problem. When I press stop, I want the program to end immediately. Instead, it waits for the timeout then displays an error message. How do I get it to end as soon as I press stop?

[JÞB]

Then you need a more suiable archetecture.  Start from a Finite measurment project template.  Call DAQmx Control Task with Abort as the input to end your task immediatly.  The DAQ assistant is not going to work for you.