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Can a NI 9403 be used for arbitrary time length 5v square wave output?

I have a cDAQ-9178 with NI 9403 module. I would like to use this module to output a 5v square wave for an arbitrary amount of time. I have tried a few methods with the most recent being a program very similar to this example : https://decibel.ni.com/content/docs/DOC-25288 . The differences being I simply fed the write a Boolean true and had it in a timed loop. Upon testing the program and monitoring the output with a BK 2553 I found that I would either get a single 2v spike or a ~1V_pp_max oscillation about the ground. I tried it on two different channels and received the same results. Please advise.
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Hi valley,

 

Can you post the code that you have been using?  This will help the community take a deeper look into your issue!

 

Thanks!

Tucker
Applications Engineering
National Instruments
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Certainly. Attached is one of the methods I used to attempt to get a square wave along with one of the aforementioned outputs as captured by my BK 2553. The final picture is what the NI 9403 outputs using the testing feture in the daq assistant. This is with continuous samples, 1kHz, and 500 samples as the settings in the assistant.

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That waveform for the DAQ_Assistant picture looks a lot like you have the oscilloscope set to AC Coupling.


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Unfortunately, it isn't in AC coupling. I switched channels on the BK 2553 and NI 9403 several times and all behaved the same regardless of this. Also, the BK 2553 performs well with a known square wave source. Although, given the new apparent instability that has appeared overnight I am starting to wonder if there is some internal fault with the NI 9403 module. This is of course barring some odd and/or buried setting that is somehow wrong for what I want to do. Thanks for the current help though.
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