JYTEK USB-61210, User Manual

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28 Operation & Calibration
Delayed-Trigger Acquisition Mode (no retriggering)
Delay-trigger acquisition is indicated when the data collection is to be
delayed following the trigger event, as shown. Delay duration is speci -
fied by a 32-bit counter value, whereby maximum delay is the period of
TIMEBASE X (2
32
- 1), and minimum delay the period of the timebase.
Figure 3-9: Delayed Trigger
Middle Trigger Mode
Middle-trigger acquisition mode is indicated when data is to be col -
lected before and after the trigger event. The amount of stored data
before and after trigger event can be set individually (M and N samples),
as shown.
Figure 3-10: Middle Trigger
Pre-Trigger Mode
Pre-trigger acquisition is indicated when data is to be collected before
the trigger event. Acquisition commences once specified function calls
are executed to begin the pre-trigger operation, and stops when the
trigger event occurs. If the trigger event occurs after the specified
amount of data has been acquired, the system stores only data preced -
ing the trigger event by a specified amount, as shown.
Time
Ɣ
Operation initiates
Trigger
Data
Ɣ
Trigger event occurs
Ɣ
Acquisition stops
Ɣ
Data transfer to system begins
N samples
Ɣ
Acquisition begins
Delay Time
Time
Ɣ Operation initiates
Ɣ Acquisition initiates
Trigger
Data
Ɣ Acquisition stops
Ɣ Data transfer to system begins
N samples M samples
Ɣ Trigger event occurs