ADLINK Technology NuDAQ PCI-9222, Руководство пользователя

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Operation Theory 33
Trigger Modes
The PCI-9222/PCI-9223 supports two trigger sources: internal
software and external digital trigger. You must select one as the
trigger event source. A trigger event occurs when the specified
condition is detected on the selected trigger source. For example,
a rising edge on the external digital trigger input.
These cards support post-trigger (with retrigger) via software or an
external digital trigger source to initiate various scan data
acquisition timing when a trigger event occurs.
Post-Trigger Acquisition (no retrigger)
Use post-trigger acquisition in applications where you want to
collect data after a trigger event. The number of scans after the
trigger is specified in the PSC_counter as illustrated in
Figure 4-5. The total acquired data length = NumChan_counter
*PSC_counter.
Figure 4-5: Post Trigger without Retrigger
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.