Ao Start Trigger Signal; Using A Digital Source - National Instruments Data Acquisition Device NI USB-621x User Manual

PFI
20 MHz Timebase
100 kHz Timebase

AO Start Trigger Signal

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Ctr n Internal Output
AO Sample Clock
Timebase
Figure 5-3. Analog Output Timing Options
USB-621x devices feature the following AO (waveform generation) timing
signals:
• AO Start Trigger Signal
• AO Pause Trigger Signal
• AO Sample Clock Signal
• AO Sample Clock Timebase Signal
Use the AO Start Trigger (ao/StartTrigger) signal to initiate a waveform
generation. If you do not use triggers, you can begin a generation with a
software command.

Using a Digital Source

To use AO Start Trigger, specify a source and an edge. The source can be
one of the following signals:
• A pulse initiated by host software
•
(USB-6211/6215 Devices)
• (USB-6212/6216 Devices)
•
(USB-6218 Devices)
• AI Start Trigger (ai/StartTrigger)
PFI
Programmable
Clock
Divider
Sample Clock
Timebase Divisor
PFI <0..3>
PFI <0..15>
PFI <0..3>, PFI <8..11>
5-5
Chapter 5 Analog Output
AO Sample Clock
NI USB-621x User Manual