Using a Digital Source
To use DO Start Trigger, specify a source and a rising or falling edge. The source can be one
of the following signals:
•
A pulse initiated by host software
•
Any PFI terminal
•
AI Reference Trigger
•
AI Start Trigger
The source also can be one of several internal signals on the cRIO controller. Refer to the
"Device Routing in MAX" topic in the
NI-DAQmx Help
or the
LabVIEW Help
for more
information.
You also can specify whether the waveform generation begins on the rising edge or falling
edge of DO Start Trigger.
Routing DO Start Trigger Signal to an Output Terminal
You can route DO Start Trigger to any output PFI terminal. The output is an active high pulse.
DO Pause Trigger Signal
Use the DO Pause Trigger signal to mask off samples in a DAQ sequence. When DO Pause
Trigger is active, no samples occur, but DO Pause Trigger does not stop a sample that is in
progress. The pause does not take effect until the beginning of the next sample.
When you generate digital output signals, the generation pauses as soon as the pause trigger is
asserted. If the source of the sample clock is the onboard clock, the generation resumes as soon
as the pause trigger is deasserted, as shown in the figure below.
Figure 43. DO Pause Trigger with the Onboard Clock Source
Pause Trigger
Sample Clock
If you are using any signal other than the onboard clock as the source of the sample clock, the
generation resumes as soon as the pause trigger is deasserted and another edge of the sample
clock is received, as shown in the figure below.
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cRIO-904x User Manual
