ADLINK USB-1210 - Manual (Page 40)

30 Operation & Calibration
acquired after the first trigger signal, after which the USB-1210
awaits the next re-trigger signal (re-trigger signals occurring
before the N samples are completed will be ignored). When the
re-trigger signal occurs, another N samples are performed. The
process repeats until the specified number of re-trigger signals are
detected.
Figure 3-12: Post Trigger with Retriggering
Gated Trigger
Gated-trigger acquisition is indicated in applications where you
want to collect data when trigger events are set to level high/low,
and hold acquisition when trigger events are set to the opposite
level.
As shown, after the operation starts, the first scan of data is imme-
diately acquired when the trigger signal is deasserted and paused
when the trigger signal is asserted.
The remaining A/D conversions are not performed until the trigger
signal is deasserted again. The process repeats until the specified
amount of data is acquired.
Figure 3-13: Gated Trigger
Time
ƔOperation initiates
Trigger
Data
ƔTrigger event occurs
ƔAcquisition initiates
N samples N samples N samples
Time
ƔOperation initiates
Trigger
(Active High)
Data
ƔAcquisition begins ƔAcquisition stops
ƔAcquisition begins ƔAcquisition stops
ƔAcquisition begins