DAQmx sampling interval

Greetings,

I have two questions probably related. A question is that I am trying to use an interval to retrieve data of a sample continuous DAQ cards (I have tested this on a 6361 and also a 16XE-10). When I run the code, I specify a sample rate and a sampling interval to choose the number of samples to receive. The number of samples to read door should how long takes it from the read operation, however, the time required to complete this operation is never my specified sampling interval which doesn't make much sense to me. In addition, the dt for my data is always 0, as if she doesn't really know the sampling frequency. This is probably a stupid mistake where I do not forget a set, but maybe someone can see my error and report to me. Thanks for the help.

Attached is an example vi that must show the question.

The sample default calendar type is "On Demand" and it doesn't seem like you have changed it.  Why not just call DAQmx Timing.vi to set the clock sample settings?  It encapsulates the property nodes that configure the sample clock calendar:

Best regards

Tags: NI Software

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