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DAQmxCfgDigEdgeStartTrig on a 6251 and not using PFI lines

All the examples of using  DAQmxCfgDigEdgeStartTrig always seem to use a PFI line, for instance "/Dev1/PFI0".  This works fine except that if I specify bit 0 of Port 0 (ie. NOT a PFI line) using "/Dev1/line0" the trigger does not seem to work but I don't get an error returned from the call to DAQmxCfgDigEdgeStartTrig either.  Anybody know if I can use one line of Port0 as my Start Trigger for a simple analog voltage task?
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Hello Lou_III,

The two common ways to trigger a task, such as simple analog acquisition, is to either use an external signal or the channel you are acquiring on. To use the external signal, you need to route the signal on a dynamic channel: a PFI line or a RTSI line are good examples. Port 0 on the 6251 contains static digital lines so cannot trigger from this port. Port 1 and port 2 on the other hand contain PFI lines, which are all eligible for triggering, assuming they are not reserved for other tasks such as counters. Hope that helps!

Regards,

Chris Behnke
Sr. RF Engineer
High Frequency Measurements
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