National Instruments PCI-6281, User Manual

Page: 85 / 298

© National Instruments
|
5-7
M Series User Manual
You also can specify whether the waveform generation begins on the rising edge or falling edge
of AO Start Trigger.
Using an Analog Source
When you use an analog trigger source, the waveform generation begins on the first rising edge
of the Analog Comparison Event signal. Refer to the
Triggering with an Analog Source
section
of Chapter 11,
Triggering
, for more information.
Routing AO Start Trigger Signal to an Output Terminal
You can route AO Start Trigger out to any PFI <0..15> or RTSI <0..7> terminal.
The output is an active high pulse. PFI terminals are configured as inputs by default.
AO Pause Trigger Signal
Use the AO Pause Trigger (ao/PauseTrigger) signal to mask off samples in a DAQ sequence.
That is, when AO Pause Trigger is active, no samples occur.
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 your sample clock is the onboard clock, the generation resumes as soon
as the pause trigger is deasserted, as shown in Figure 5-4.
Figure 5-4.
AO Pause Trigger with the Onboard Clock Source
If you are using any signal other than the onboard clock as the source of your 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 Figure 5-5.
Figure 5-5. AO PauseTrigger with Other Signal Source
P aus e Trigger
Sa mple Clock
P aus e Trigger
Sa mple Clock