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How to export a clock in PCI 6534

I have a very simple question.

I am using PCI 6534 and I would like to export the sample clock to an output pin.  The code is as following:

.....

    DAQmxErrChk (DAQmxCreateTask("",&taskHandle));
    DAQmxErrChk (DAQmxCreateDOChan(taskHandle,"Dev4/port0/line0:7","",DAQmx_Val_ChanPerLine));
    DAQmxErrChk (DAQmxCfgSampClkTiming(taskHandle, NULL,1000.0,DAQmx_Val_Rising,DAQmx_Val_ContSamps,1000));
    DAQmxErrChk (DAQmxExportSignal(taskHandle, DAQmx_Val_SampleClock, "/Dev4/pfi2"));
.....

In the last line, I exported the sample clock to pin pfi2.  But when I hooked up an oscilloscope to pfi2 (pin 2 on PCI 6534) I observed no clock signal.  All I saw was a signal at ground voltage level.  What's wrong?

Thanks,
-Andrew
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There is a clock edge for every sample generated.  When you start the task, the clock should start pulsing.
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But ... that's exactly what I did and I didn't get any signal.
 
-Andrew
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Hello Andrew,

Do you see the same behavior if you export the sample clock to /Dev4/PFI6?

Regards,

Micaela N
National Instruments
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