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Retriggerable external digital trigger for analog output

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Goal:

Output a finite waveform every time external trigger is detected (multiple times in a single run)

 

Problem:

I planned to modify this example: http://www.ni.com/example/29787/en/

After downloading this example and testing it, I noticed a continuous output, even when I did not activate my external trigger at all.

 

Questions:

Why is there a continuous output signal when I start the program, despite the absence of any trigger?

Is there any way to modify waveform length coming out of the waveform buffer generation.vi (or function generator.vi)? It appears to always give a second's worth of data despite changing any of the input parameters

 

Any input is appreciated!

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Solution
Accepted by topic author azthlbs

The default values for that code example should have required a trigger signal at PFI0 before any samples were generated.  Did you change any of the config parameters on the front panel, even if you didn't change any of the code?

 

Also, what DAQ device are you using?   Some newer devices would support retriggering an AO task directly, without needing to do things indirectly with the counter task.  That would be a lot more straightforward if you have hardware to support it.

 

 

-Kevin P

CAUTION! New LabVIEW adopters -- it's too late for me, but you *can* save yourself. The new subscription policy for LabVIEW puts NI's hand in your wallet for the rest of your working life. Are you sure you're *that* dedicated to LabVIEW? (Summary of my reasons in this post, part of a voluminous thread of mostly complaints starting here).
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Turns out DAQ didn't need counter. Thanks!

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