Using A Digital Source; Using An Analog Source; Routing Ai Reference Trigger Signal To An Output Terminal - National Instruments NI 6221 User Manual

Chapter 4 Analog Input
M Series User Manual
When the reference trigger occurs, the DAQ device continues to write
samples to the buffer until the buffer contains the number of posttrigger
samples desired. Figure 4-23 shows the final buffer.
Reference Trigger
Pretrigger Samples
Figure 4-23. Reference Trigger Final Buffer

Using a Digital Source

To use ai/ReferenceTrigger with a digital source, specify a source and an
edge. The source can be any of the following signals:
• PFI <0..15>
• RTSI <0..7>
• PXI_STAR
The source also can be one of several internal signals on your DAQ device.
Refer to Device Routing in MAX in the NI-DAQmx Help or the LabVIEW
Help in version 8.0 or later for more information.
You also can specify whether the measurement acquisition stops on the
rising edge or falling edge of ai/ReferenceTrigger.

Using an Analog Source

When you use an analog trigger source, the acquisition stops on the first
rising edge of the Analog Comparison Event signal.
Routing AI Reference Trigger Signal to an Output
Terminal
You can route ai/ReferenceTrigger out to any PFI <0..15> or RTSI <0..7>
terminal.
All PFI terminals are configured as inputs by default.
Posttrigger Samples
Complete Buffer
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