© National Instruments
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NI cDAQ-9181/9184/9188/9191 User Manual
AI Pause Trigger Signal
You can use the Pause Trigger to pause and resume a measurement acquisition. The internal
sample clock pauses while the external trigger signal is active and resumes when the signal is
inactive. You can program the active level of the pause trigger to be high or low.
Using a Digital Source
To use the Pause Trigger, specify a source and a polarity. The source can be either from PFI or
one of several other internal signals on your cDAQ chassis. Refer to the
Device Routing in MAX
topic in the
NI-DAQmx Help
or the
LabVIEW Help
for more information.
Using an Analog Source
Some C Series modules can generate a trigger based on an analog signal. In NI-DAQmx, this is
called the Analog Comparison Event.
When you use an analog trigger source, the internal sample clock pauses when the Analog
Comparison Event signal is low and resumes when the signal goes high (or vice versa).
Note
Depending on the C Series module capabilities, you may need two modules
to utilize analog triggering.
Note
Pause triggers are only sensitive to the level of the source, not the edge.
Getting Started with AI Applications in Software
You can use the cDAQ chassis in the following analog input applications:
•
Single-point acquisition
•
Finite acquisition
•
Continuous acquisition
For more information about programming analog input applications and triggers in software,
refer to the
NI-DAQmx Help
or the
LabVIEW Help
for more information.