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. 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 User Manual.

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 on an installed C Series module
  • AI Reference Trigger
  • AI Start Trigger

The source also can be one of several internal signals on the cDAQ chassis. Refer to the Device Routing in MAX topic in the NI-DAQmx User Manual for more information.

You also can specify whether the waveform generation begins on the rising edge or falling edge of AO Start Trigger.

Using an Analog Source

Some C Series modules can generate a trigger based on an analog signal. In NI-DAQmx, this is called the Analog Comparison Event, depending on the trigger properties.

When you use an analog trigger source, the waveform generation begins on the first rising or falling edge of the Analog Comparison Event signal, depending on the trigger properties. The analog trigger circuit must be configured by a simultaneously running analog input task.

Note Depending on the C Series module capabilities, you may need two modules to utilize analog triggering.

Using a Time Source

To use AO Start Trigger signal with a time source, specify a specific time in NI-DAQmx. Refer to Timing and Triggering in the NI-DAQmx User Manual for more information on accessing time-based features in the NI-DAQmx API.

Routing AO Start Trigger Signal to an Output Terminal

You can route AO Start Trigger to any output PFI terminal on an installed C Series module. The output is an active high pulse.