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3�4 Trigger Modes
Trigger modes applied to trigger sources initiate different data acquisition timings when a
trigger event occurs. The following trigger mode descriptions are applied to analog input
function.
3�4�1 Post Trigger Mode
Post-trigger acquisition is applicable when data is to be collected after the trigger event,
as shown. When the operation starts, PCIe-69814 waits for a trigger event. Once the
trigger signal is received, acquisition begins. Data is generated from ADC and transferred
to system memory continuously. The acquisition stops once the total data amount reaches
a predefined value.
Figure 3-6: Post-Trigger Acquisition
Figure 3-6: Post-Trigger Acquisition
3�4�2 Delayed Trigger Mode
Delayed-trigger acquisition is utilized to postpone data collection after the trigger event,
as shown. When PCIe-69814 receives a trigger event, a time delay is implemented before
commencing acquisition. The delay is specified by a 16-bit counter value such that a
maximum thereof is the period of TIMEBASE X (216), and the minimum is the Timebase
period.
Figure 3-7: Delayed Trigger Mode Acquisition
