JYTEK USB-62405, Руководство пользователя

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38 Operation
and after trigger event can be set individually (M and N samples), as
shown. Please note that M+N must be equal to or less than 8k samples
for all analog input channels, and that the trigger event can only be
accepted when the specified amount of data has been acquired (M sam -
ples), otherwise the trigger event will be ignored.
Figure 3-13: Middle-Trigger Acquisition
Gated Trigger
Gated-trigger acquisition is indicated in applications where data is to be
collected when trigger events are set to level high/low, and acquisition
suspended when trigger events are set to the opposite level. The pro -
cess repeats until the specified amount of data is acquired.
Figure 3-14: Gated Trigger
Post-Trigger or Delay-Trigger Acquisition with Re-Trigger
Post-trigger or delay-trigger acquisition with re-trigger function is indi -
cated in applications where data is to be collected after several trigger
events. The number of scans after each trigger and the re-trigger num -
ber are valid from 1 to the buffer size allocated in kernel space. The pro -
cess repeats until the specified amount of re-trigger signals is detected.
Time
Ɣ Operation start
Ɣ Acquisition start
Trigger
Data
Ɣ
Trigger Event Occurs
Ɣ Acquisition stop
Ɣ
Begin to transfer data to
system
N samples
This data is
discarded.
Only acquired N
samples will be
transferred back to
system.
Time
Ɣ Operation start
Ɣ Acquisition start
Trigger
Data N samples M samples
Ɣ
Trigger event occurs
(high active)
Ɣ
Trigger event occurs
(high active)
ƔƔƔƔ