Chapter4 ConnectingSignals
©NationalInstruments Corporation 4-21 NI6013/6014 User Manual
As aninput, each PFI pin can be individually configured for edge or level
detection and for polarity selection. Youcan use the polarity selection for
anyof the timing signals, but the edge or level detection depends upon the
particular timing signal being controlled. The detection requirements for
eachtiming signal are listed within the section that discusses that individual
signal.
In edge-detection mode, the minimum pulse width required is 10 ns. This
applies for both rising-edge and falling-edge polarity settings. There is no
maximumpulse-width requirement in edge-detect mode.
In level-detectionmode, there are no minimum or maximum pulse-width
requirements imposed by the PFIs themselves, butthere may be limit s
imposed bythe part icular timing signal being controlled. These
requirementsare listed later in this chapter.
DAQ Timing ConnectionsTheDAQ timing signals are TRIG1, TRIG2, STARTSCAN, CONVERT*,
AIGATE,SISOURCE, SCANCLK, and EXTSTROBE*.
Posttriggereddata acquisition allows you to view only data that is acquired
aftera trigger eventis received. A typical posttriggered DAQ sequence is
showninFigure4-11.
Figure4-11. Typical Posttriggered Acquisition
13042
TRIG1
STARTSCAN
CONVERT*
ScanCounter