ADLINK Technology NuDAQ PCI-9222, Руководство пользователя

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34 Operation Theory
Use Retrig_no to specify the re-trigger numbers. In Figure 4-6,
two scans of data are acquired after the first trigger signal, then
the card waits for the retrigger signal (retrigger signals which
occur before the scans are completed will be ignored). When
the retrigger signal occurs, two more scans are performed. The
process repeats until the specified amount of retrigger signals
are detected.
The total acquired data length = NumChan_counter
*PSC_counter * Re-trig_no. For infinite retrigger, the retrig_no
is set to 0.
Figure 4-6: Post Trigger with Retrigger
Gated Trigger
Use the gated-trigger acquisition function in applications where
you want to collect data when trigger events are set to level
high/low, and hold acquisition when trigger events are set to
the opposite level.
The number of scans after each trigger is specified in the
PSC_counter. In Figure 4-7, after the operation starts, the first
scan of data is immediately acquired when the trigger signal is
disasserted and paused at the second scan when the trigger
signal is asserted.
The four remaining scans are not performed until the trigger
signal is disasserted again. The process repeats until the
specified amount of retrigger signals are detected.