Digital Input Triggering Signals
- Updated2024-12-11
- 1 minute(s) read
A trigger is a signal that causes an action, such as starting or stopping the acquisition of data. When you configure a trigger, you must decide how you want to produce the trigger and the action you want the trigger to cause. The cDAQ chassis supports internal software triggering, external digital triggering, analog triggering, and internal time triggering.
Three triggers are available: Start Trigger, Reference Trigger, and Pause Trigger. An analog or digital trigger can initiate these three trigger actions. Time can also initiate the Start Trigger. Up to two C Series parallel digital input modules can be used in any chassis slot to supply a digital trigger. To find your module triggering options, refer to the documentation included with your C Series modules. For more information about using analog modules for triggering, refer to Analog Input Triggering Signals and Analog Output Triggering Signals.
Refer to DI Start Trigger Signal, DI Reference Trigger Signal, and DI Pause Trigger Signal for more information about the digital input trigger signals.
Related Information
- Analog Input Triggering Signals
A trigger is a signal that causes an action, such as starting or stopping the acquisition of data. When you configure a trigger, you must decide how you want to produce the trigger and the action you want the trigger to cause. The cDAQ chassis supports internal software triggering, external digital triggering, analog triggering, and internal time triggering.
- Analog Output Triggering Signals
A trigger is a signal that causes an action, such as starting or stopping the acquisition of data. When you configure a trigger, you must decide how you want to produce the trigger and the action you want the trigger to cause. The cDAQ chassis supports internal software triggering, external digital triggering, analog triggering, and internal time triggering.
- DI Start Trigger Signal
Use the DI Start Trigger (di/StartTrigger) signal to begin a measurement acquisition. A measurement acquisition consists of one or more samples. If you do not use triggers, begin a measurement with a software command. Once the acquisition begins, configure the acquisition to stop in one of the following ways:
- DI Reference Trigger Signal
Use a reference trigger (di/ReferenceTrigger) signal to stop a measurement acquisition. To use a reference trigger, specify a buffer of finite size and a number of pretrigger samples (samples that occur before the reference trigger). The number of posttrigger samples (samples that occur after the reference trigger) desired is the buffer size minus the number of pretrigger samples.
- DI Pause Trigger Signal
You can use the DI Pause Trigger (di/PauseTrigger) signal to pause and resume a measurement acquisition. The internal sample clock pauses while the external trigger signal is active and resumes when the signal is inactive. You can program the active level of the pause trigger to be high or low.