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3�4�3 Pre-Trigger Mode
Collects data before the trigger event, starting once specified function calls are executed to
begin the pre-trigger operation, and stopping when the trigger event occurs. If the trigger
event occurs after the specified amount of data has been acquired, the system stores only
data preceding the trigger event by a specified amount, as follows.
Time
Operation start
Acquisition start
Trigger
Data
Trigger Event Occurs
Acquisition stop
Data transfer to system begins
N samples
X samples have been acquired
before trigger occurs, where X<N
Trigger signals occuring before the specified
amount of data has been acquired are ignored
Figure 3-8: Pre-Trigger Mode Acquisition
3�4�4 Middle Trigger Mode
Collects data before and after the trigger event, with the amount to be collected set
individually (M and N samples), as follows
Time
Operation start
Acquisition start
Trigger
Data
Acquisition stop
Data transfer to system begins
N samples
M samples
Trigger event occurs
Figure 3-9: Middle Trigger Mode Acquisition
3.4.5 Acquisition with Re-Triggering
A digitizer acquires a trace of N samples/channel for a single acquisition. Re-Trigger mode
can also be set to automatically acquire R traces, containing N*R samples/channel of data,
without additional software intervention.
The Re-Trigger setting can be used for Post-Trigger and Delayed Trigger modes, with different