Aegis OSC-9200, Руководство пользователя

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Trigger Mode
The oscilloscope’s trigger mode includes auto, normal, single and Force. The mode affects how the
oscilloscope searches for the trigger event.
After the oscilloscope starts running, it first fills the pre-trigger buffer. After the pre-trigger buffer is
filled, it begins to search for a trigger. Data continues to flow through this buffer while the scope
searches for the trigger. As the scope continues to search, overflow from the pre-trigger buffer is
discarded on a first-in, first-out basis.
When a trigger is found, the oscilloscope fills the post- trigger buffer and displays the acquisition
memory.
Press the
Trigger Setup button and Mode F key to select the desired trigger mode.
Ø
In the Auto trigger mode (the default setting), if the specified trigger conditions are not found,
triggers are forced and acquisitions are made so that signal activity is displayed on the
oscilloscope.
The
Auto trigger mode is appropriate when:
l
Checking DC signals or signals with unknown levels or activity.
l
Trigger events occur often enough that forced triggers are unnecessary.
Ø
In the Normal trigger mode, triggers and acquisitions only occur when the specified trigger
conditions are found. Otherwise, the oscilloscope holds the original waveform and waits for the
next trigger.
The
Normal trigger mode is appropriate when:
l
You only want to acquire specific events specified by the trigger settings.
l
Triggering on an infrequent signal from a serial bus (for example, I2C, SPI, CAN, LIN, etc.) or
another signal that arrives in bursts. The
Normal trigger mode lets you stabilize the display
by preventing the oscilloscope from auto-triggering.
Ø
In the Single trigger mode, the oscilloscope waits for a trigger, displays the waveform when the
trigger condition is met, and stops.
The
Single trigger mode is appropriate when you want:
l
To capture a single event or a periodic signal.
l
To capture a burst or other unusual signals.
Ø
In the Force trigger mode, when the trigger condition is not met, it will be force triggered after
the frame is acquired. The trigger status in the upper left corner of the screen will be displayed as
"FStop".