ADLINK Technology USB-1901, User Manual

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44 Operation
4.4.1 Post-Trigger Acquisition Mode (no retriggering)
Post-trigger acquisition is indicated in applications where data is to
be collected after a trigger event. The number of scans for each
channel after triggering is specified in the PSC_counter as shown.
The total acquired data length = NumChan_counter *
PSC_counter.
Figure 4-7: Post Trigger without Retriggering
4.4.2 Delayed-Trigger Acquisition Mode (no
retriggering)
Delayed-trigger acquisition is indicated to delay data collection
after the occurrence of a specified trigger event. The delay time is
controlled by the value, pre-loaded in the Delay_counter (16nn).
The counter calculates down on the rising edge of the
Delay_counter clock source after the trigger condition is met. The
clock source can be software programmed by the timebase clock
(80 MHz). When the count reaches 0, the counter stops and the