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Acquisition and restitution of an analog signal

Hello,

 

I will start by describing my equipment:

  • a PXIe-1062Q backplane;
  • a PXIe-8880 controler with Windows 10 and Labview full development;
  • a PXI-6341 multifonction board.

I try to make the acquisition of an analog signal, then modify it's amplitude through labview and finally regenerate it on an analog output of the PXI-6341 board. To notice that i make the acquisition on other channels at the same time.

 

I'd like to reduce to the minimum the delay between the input and the output and this delay must not drift over long time duration.

 

Any advice?

 

P.S : I made a lot of tests, i reach a minimum delay of ten milisecondes but it drift.

 

Thanks you for any answer you may give to me.

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@Compas wrote:

P.S : I made a lot of tests, i reach a minimum delay of ten milisecondes but it drift.


Post the code.

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Find attached the code.

 

This code works fine with approximatively 5ms delay with no drift but when i integrate it in a more complexe software it no longer works and i need to increase output buffer to 20000 samples to avoid writing errors.

 

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That code is fine, and will have delay due to the length of the loop iteration. If the problem only occurs when you integrate it into larger, more complex use cases, then we need to see those use cases (because the problem is with the method of integration).


GCentral
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I found the problem yesterday by deleting added elements in the loop.

It was a call of a global variable that is called in multiple other threads.

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