Ao Sample Clock Timebase Signal; Ao Start Trigger Signal; Routing Ao Start Trigger Signal To An Output Terminal - National Instruments NI cRIO-905x Series User Manual

AO Sample Clock Timebase Signal

The AO Sample Clock Timebase signal is divided down to provide a source for AO Sample
Clock. AO Sample Clock Timebase can be generated from external or internal sources, and is
not available as an output from the controller.
Delta-Sigma Modules
The oversample clock is used as the AO Sample Clock Timebase. The cRIO controller
supplies 10 MHz, 12.8 MHz, and 13.1072 MHz timebases. When delta-sigma modules with
different oversample clock frequencies are used in an analog output task, the AO Sample
Clock Timebase can use any of the available frequencies; by default, the fastest available is
used. The update rate of all modules in the task is an integer divisor of the frequency of the
AO Sample Clock Timebase.
Note
DSA modules do not support HWTSP mode.

AO Start Trigger Signal

Use the AO Start Trigger signal to initiate a waveform generation. If you do not use triggers,
you can begin a generation with a software command. If you are using an internal sample
clock, you can specify a delay from the start trigger to the first sample. For more information,
refer to the NI-DAQmx Help.
Using a Digital Source
To use AO 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 AO Start Trigger.

Routing AO Start Trigger Signal to an Output Terminal

You can route AO Start Trigger to any output PFI terminal. The output is an active high pulse.
Using a Time Source
To use the Start Trigger signal with a time source, configure a specific time in NI-DAQmx.
Refer to the "Timestamps" and "Time Triggering" topics in the NI-DAQmx Help for more
information on accessing time-based features in the NI-DAQmx API.
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