National Instruments Data Acquisition Device E Series - Manual (Page 69)

Chapter 2 Analog Input
E Series User Manual 2-36 ni.com
Using an Analog Source
When you use an analog trigger source, the acquisition stops on the first
rising edge of the Analog Comparison Event signal. Refer to Chapter 10,
Triggering , for more information on analog triggering.
Outputting the AI Reference Trigger Signal
You can configure the PFI 1/AI REF TRIG pin to output the
ai/ReferenceTrigger signal. The output pin reflects the ai/ReferenceTrigger
signal regardless of what signal you specify as its source.
The output is an active high pulse. Figure 2-23 shows the timing behavior
of the PFI 1/AI REF TRIG pin configured as an output.
Figure 2-23. PFI 1/AI REF TRIG Timing Behavior
The PFI 1/AI REF TRIG pin is configured as an input by default.
AI Pause Trigger Signal
You can use the AI Pause Trigger (ai/PauseTrigger) signal to pause and
resume a measurement acquisition. This signal is not available as an output.
Using a Digital Source
To use ai/PauseTrigger, specify a source and a polarity. The source can be
an external signal connected to any PFI or RTSI <0..6> pin. 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 8.x Help
for more information.
Also, specify whether the measurement sample is paused when
ai/PauseTrigger is at a logic high or low level.
t
w
t
w
= 50 to 100 ns