frequency of the loop

Hello

I have a doubt. I use assistant daq AND acquire a signal from a device. I read 6 channels simultaneously and continuously, at 1 kHz.

However, I checked the loop where the whole process is performed done 10 iterations in 1 second, that give me 6 channels x 1 sample/channel, 60 samples per second. (or 10 samples/channel)

This is a little far the 1 kHz than I expected. The loop has no delay, nothing related with the time... I'm confusing, something is missing, or my computer cannot process the cycle faster than 10 Hz?

Help, please...

Thanks in advance

It's not because you have a frequency of 1 kHz your loop iteration in LabView to work in 0.001 s

The stamp on the DAQ will capture samples x and with a statement 'DAQmx read' you read x samples at a time.

If configure you your task DAQmx to read 2000 samples 'Samples to Read' in the tab 'Configuration' or wire to the connector 2000 'number of samples per channel' from the 'read DAQmx' vi, this vi will wait for 2 seconds.

You can then average these readings of 2000 with the vi "means."

Hope this has helped

Tags: NI Software

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