what are pfi lines for triggering in DAQmx??

[dzhuang]

Hi i am very new to labview and im doing a lot of research on DAQmx for labview. I came across triggering and what i am unable to find is what exactly are the PFI lines used as trigger sources in triggering. Furthermore what is its function and how do i use it in my program to create an analog edge trigger? my device is pxi-6221. Thanks!

[NIquist]

PFI = Programmable Function Interface.  They're used as auxilary DAQ connections for trigein, etc.

See chapter 8 of your M-series manual: http://digital.ni.com/manuals.nsf/websearch/2025C99AB0614F9E8625748000577B9A