National Instruments DAQ X NI 634 Series, Руководство пользователя

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X 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 6-5 shows the final buffer.
Figure 6-5. Reference Trigger Final Buffer
Using a Digital Source
To use DI Reference Trigger 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
• PXIe_DSTAR<A,B>
• Change Detection Event
• Counter n Internal Output
• AI Reference Trigger (ai/ReferenceTrigger)
• AO Start Trigger (ao/StartTrigger)
• DO Start Trigger (do/StartTrigger)
The source can also 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 for more information.
You can also specify whether the measurement acquisition stops on the rising or falling edge or
falling edge of DI Reference Trigger.
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 DI Reference Trigger Signal to an Output Terminal
You can route DI Reference Trigger out to any PFI <0..15>, RTSI <0..7>, PXI_Trig <0..7>, or
PXIe_DSTARC terminal. All PFI terminals are configured as inputs by default.
Reference Trigger
Pretrigger Sa mple s
Complete B u ffer
Po s ttrigger Sa mple s