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Appendix B
Timing Signal Information
B-2
ni.com
DAQ Timing Connections
The timing signals are AI START TRIG, AI REF TRIG, AI SAMP CLK,
AI CONV CLK, AI PAUSE TRIG, AI SAMPLE CLK TIMEBASE, and
AI HOLD COMPLETE.
Posttriggered DAQ allows you to view data that is acquired after a trigger
event is received. Figure B-1 shows a typical posttriggered sequence.
Figure B-1.
Typical Posttriggered Sequence
Pretriggered DAQ allows you to view data that is acquired before the
trigger of interest in addition to data acquired after the trigger. Figure B-2
shows a typical pretriggered sequence.
Figure B-2.
Typical Pretriggered Sequence
1
3
0
4
2
AI
S
TART TRIG
AI
S
AMP CLK
AI CONV CLK
S
c
a
n Counter
n/
a
0
1
2
3
1
0
2
2
2
AI
S
TART TRIG
AI REF TRIG
AI
S
AMP CLK
AI CONV CLK
S
c
a
n Counter