National Instruments PCIe-6323 - AI Pause Trigger Signal

4-34 | ni.com
Chapter 4 Analog Input
AI Pause Trigger Signal
Use the AI Pause Trigger (ai/PauseTrigger) signal 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, as shown in Figure 4-24. In the figure, T represents the period, and A represents the
unknown time between the clock pulse and the posttrigger.
Figure 4-24. Halt (Internal Clock) and Free Running (External Clock)
Using a Digital Source
To use AI Pause Trigger, specify a source and a polarity. The source can be any of the following
signals:
• PFI <0..15>
•RTSI <0..7>
• PXI_STAR
• PXIe_DSTAR<A,B>
• Counter n Internal Output
• Counter n Gate
• AO Pause Trigger (ao/PauseTrigger)
• DO Pause Trigger (do/PauseTrigger)
• DI Pause Trigger (di/PauseTrigger)
The source can also be one of several other internal signals on your DAQ device. Refer to Device
Routing in MAX in the NI-DAQmx Help or the LabVIEW Help for more information.
AI Sample Clock
AI Convert Clock
AI Pause Trigger
T
A
AI External Sample Clock
AI Convert Clock
AI Pause Trigger
Halt. Used on Internal Clock
Free Running. Used on External Clock
T – A
AI Sample Clock