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Is there a way to trigger a PXIe-6556 PPMU measurement while the instrument is running a digital pattern?

I'd like to be able to take measurements with the PXIe-6556's PPMU(s) while the instrument is running a digital pattern. While it is possible to output an event trigger from a pattern step while it is running, I haven't found a way to get the event trigger to trigger a PPMU measurement.

Is there a way to trigger the PPMU to take a measurement versus having to halt the pattern and take a measurement?

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Mahtomedite,
 

Since the component is software timed, unfortunately the only way to do so would be to trigger the PPMU, halt the pattern, and then take a measurement as you mentioned. There is not a method of taking measurement while the PPMU is triggering.

 

Regards,

Ali S.
Applications Engineering
National Instruments
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I was thinking more along the lines of routing the event trigger to PFI1 and using PFI1 as the PXI trigger source input to a VI similar to that used in the example

"Cont Acq Multiple Samples -Ext Trig - Ext SampleTrig.vi" 

 

In the PPMU VI case, the VI could be activated by the PXI trigger and execute a PPMU measurement (assuming that a PPMU measurement is independent of the pattern running).

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In my particular case, the plan was to run a pattern on a PXIe-6570 that steps with an event trigger op code, tie the event trigger to a PXI trigger and use that to generate a trigger mechanism that a VI can pick up and use as a software trigger to take a PPMU measurement on a PXIe-6556. In this particular case, the 6556 is not running a pattern at the same time, so what I brought up earlier shouldn't be a problem. Turn around time will probably be the biggest issue because the pattern will continue running. The PPMU's minimum aperture setting is 4uS. I haven't timed the PPMU measure VI yet.

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Mahtomedite,

 

 That's interesting since the PXIe-6570 is on a pattern based system and the PXIe-6556 uses a time signal so I didn't think of such a configuration.

 

If you can or would have time, I'd be interested (and it would be beneficial for the forum) to see the PPMU Measure VI time in this situation.

Regards,

Ali S.
Applications Engineering
National Instruments
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