Chapter 4
Connecting the Signals
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In edge-detection mode, the minimum pulse width required is 10 ns. This
requirement applies for both rising-edge and falling-edge polarity settings.
There is no maximum pulse width requirement in edge-detect mode.
In level-detection mode, there are no pulse width requirements imposed by
the PFIs themselves. Limits can be imposed by the particular timing signal
being controlled. These requirements are listed in the sections describing
the particular signals.
Data Acquisition Timing Connections
The timing signals are TRIG1, TRIG2, STARTSCAN, CONVERT*,
AIGATE, SISOURCE, SCANCLK, and EXTSTROBE*.
Posttriggered data acquisition allows you to view data that is acquired after
a trigger event is received. Figure 4-15 shows a typical posttriggered
sequence.
Figure 4-15.
Typical Posttriggered Sequence
Pretriggered data acquisition allows you to view data that is acquired before
the trigger of interest in addition to data acquired after the trigger.
Figure 4-16 shows a typical pretriggered sequence. The description for
each signal shown in these figures is included in this chapter.
1
3
0
4
2
TRIG1
STARTSCAN
CONVERT*
Scan Counter
