Chapter 5
Counters
Analog Output Series User Manual
5-2
ni.com
Pause Trigger
You can use pause triggers in edge counting and continuous pulse
generation applications. For edge counting acquisitions, the counter stops
counting edges while the external trigger signal is low and resumes when
the signal goes high or vice versa. For continuous pulse generations, the
counter stops generating pulses while the external trigger signal is low and
resumes when the signal goes high or vice versa.
Counter Timing Signals
The following sections contain information on counter timing signals.
Counter Timing Summary
Figure 5-2 shows the timing requirements for the gate and source input
signals and the timing specifications for the output signals on your device.
Figure 5-2.
Gate and Source Input Timing Requirements
The gate and out signal transitions shown in Figure 5-2 are referenced to
the rising edge of the source signal. This timing diagram assumes that the
counters are programmed to count rising edges. The same timing diagram,
V
IH
S
OURCE
GATE
OUT
V
IL
V
IH
V
IL
V
OH
V
OL
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e Width
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10 n
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te Hold Time
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t Del
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rce Clock Period
