Measure the frequency of the pulses PXI-6624

Hello.  I work with a PXI-6624 and am interested to make measurements of pulsed frequency for frequency and duty cycle on its inputs using DAQmx.

When I go to create the virtual channel, however, I have error-200431:

"Physical channel selected does not support the type of measure required by the virtual channel you create."

' Asked the value: pulse frequency.

«You can select: frequency, period, pulse width, period of Semi, separation of the two edges, Position:...» »

Is this card really not capable of doing these measures of pulse frequency?

Yes, the "Pulse" (not to be confused with "Pulse Width") measure was introduced with STC3 of OR including CompactDAQ and X series devices.

Measuring the pulse:

However, you should always be able to measure the frequency and the duty cycle on your card with a half measure:

The half measure:

The images are in the X Series user manual.

The difference between these two modes boils down to how the data is stored and implemented in buffer on the map - with the period semi method that the material does not distinguish between high and low samples and puts everything in a single buffer.  However, if you start the meter on the song (see below the node property), then you would know the order of low and high samples in software, and are easy enough to calculate cycle frequency and the duty of this.

Best regards

Tags: NI Hardware

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