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Acquire analog signal using cRIO Scan Interface

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Hello All,
I'm new to LabVIEW and I'm trying to perform a very simple task (at least I thought so), acquire a sine wave - 1KHz, 2Vpp, from signal generator using cRIO-9035 in Scan Interface mode with NI-9205, LabVIEW 2017 on Windows 10.
My program (also attached):

But the signal that I see is not 1kHz, it's much lower. Clearly I'm missing something.
In addition, when observing the AI channel in NI Distributed System Manager, same thing - the signal is much slower than the generated frequency.


Any assistance will be much appreciated.



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Accepted by IG.B

What is the scan engine speed? Is it picking up samples quicker than 1Khz

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You can't really push the scan engine to be faster than 1kHz.  So based on Nyquist, you can only see a signal that is up to 500Hz.  You probably really want to sample at 10kHz in order to get a good representation of your signal.  Therefore, you will need to use the FPGA to read the signal and use a DMA FIFO to send the data to the RT system.

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Message 3 of 5

I totally forgot about it...

Thanks for pointing out the basics!

But I still can't figure out how to view the AI channel in Distributed System Manager program...

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Message 4 of 5

Tools->Distribution System Manager

Select your cRio->Expand


Click on which mod's output you want to see and expand. See output by clicking on AI0, AI1, etc.

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