Hi Andrew
If you wan to control the pulse rate of your experiment, you have to program your signal into your card once for ever (for exemple, you generate a 10Hz square wave and you put it in the buffer of your card, and set it to run continuously).
Then you have a very accurate generation.
Further, LabVIEW is accurate. You can change the priority of your VI so that it forces Windows to give LabVIEW more control on the CPU use
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