AO Pause Trigger Signal
Use the AO Pause Trigger signal to mask off samples in a DAQ sequence. When AO Pause
Trigger is active, no samples occur, but AO 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 analog 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 following figure.
Figure 38. AO 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 following figure.
Figure 39. AO Pause Trigger with Other Signal Source
Pause Trigger
Sample Clock
Using a Digital Source
To use AO Pause Trigger, specify a source and a polarity. The source can be a PFI signal or
one of several other internal signals on the cRIO controller.
You also can specify whether the samples are paused when AO Pause Trigger is at a logic high
or low level. Refer to the "Device Routing in MAX" topic in the
NI-DAQmx Help
or the
LabVIEW Help
for more information.
Minimizing Glitches on the Output Signal
When you use a DAC to generate a waveform, you may observe glitches on the output signal.
These glitches are normal; when a DAC switches from one voltage to another, it produces
glitches due to released charges. The largest glitches occur when the most significant bit of the
DAC code changes. You can build a lowpass deglitching filter to remove some of these
glitches, depending on the frequency and nature of the output signal. Go to
more information about minimizing glitches.
NI cRIO-905x User Manual
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© National Instruments
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