JYTEK NuDAQ PCI-69222, User Manual

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Operation Theory 35
Post-Trigger Acquisition (with retrigger)
Use post-trigger acquisition with retrigger function in
applications where you want to collect data after several trigger
events. The number of scans after each trigger is specified in
PSC_counter and are programmable.
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.