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Measuring high frequency clocks with a PXIe-6341?

I have a PXIe-6341 Multifunction DAC and Labview 2013.


I have a couple of PCBs with 8MHz & 32MHz clocks and was wondering if I can measure these

clocks with Labview and this hardware. Not sure if the PXIe-6341 Multifunction DAC has the bandwidth

and/or there are any Labview VIs that can scale these clocks down to get an accurate measurement.


Can anyone on this forum offer some constructive ideas on how to do this?


Thanks in advance



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Unless you have a way to get the signal onto one of the PXIe-DSTAR lines, the bandwidth of the PFI lines is going to limit you to frequencies of about 25 MHz (confusingly referred to as the "External Base Clock Frequency" in the specifications).


8 MHz should be fine.  Perhaps you could divide down the 32 MHz externally (16 MHz should be fine as well) before wiring it to the X Series.


Once you get the signal into the X Series, you would use one of the onboard counters to measure frequency using one of the various methods availabe (described in the X Series User Manual).  I'd suggest the sample clocked method since it provides consistent accuracy and measurement time regardless of the exact input frequency (though the high frequency 2 counter method would be another option as well).



Best Regards,

John Passiak
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Thanks John-

Looks like the PXI Express Differential Star Trigger Lines are only available on the NI PXIe-6535/6536/6537

which I don't have...


Regarding your suggestion about using a sample clocked method, is this the same as

Single Point (On-Demand) Edge Counting?

Best Regards


Jeff P.

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The X Series can count a signal on the PXIe D-Star lines, but the timing/sync hardware necessary to drive them is expensive.  I just mentioned it just in case, I wouldn't go this route unless you already had something capable of driving them.


The sample clocked method is not the same as Single Point (On-Demand) Edge Counting.  It would be configured something like this.



Best Regards,

John Passiak
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