Trigger Mode - Rigol DS2000E Series User Manual

Chapter 5 To Trigger the Oscilloscope RIGOL

Trigger Mode

The following is the schematic diagram of the acquisition memory. To easily
understand the trigger event, the acquisition memory is divided into the pre-trigger
buffer and post-trigger buffer.
Trigger Event
ost-trigger
Pre-trigger Buffer
P Buffer
Acquisition memory
Figure 5-1 Schematic Diagram of the Acquisition Memory
After the system runs, the oscilloscope operates by first filling the pre-trigger buffer.
It starts searching for a trigger after the pre-trigger buffer is filled. While searching
for the trigger, the data sampled will still be transmitted to the pre-trigger buffer (the
new data will continuously overwrite the previous date). When a trigger is found, the
pre-trigger buffer contains the data acquired just before the trigger. Then, the
oscilloscope will fill the post-trigger buffer and display the data in the acquisition
memory. If the acquisition is activated via RUN/STOP, the oscilloscope will repeat
this process; if the acquisition is activated via SINGLE, the oscilloscope will stop
after finishing a single acquisition (you can pan and zoom the waveform currently
displayed).
Press MODE in the trigger control area (TRIGGER) on the front panel or press
MENU  Sweep to select the desired trigger mode. The corresponding status light
of the mode currently selected turns on.
Auto:
In this trigger mode, the oscilloscope will trigger and sample to display the
waveforms forcibly if no specified trigger condition is found.
This trigger mode is applicable to the following conditions: the signal level is
unknown; the DC should be displayed; the trigger condition always occurs; forcible
trigger is not required.
DS2000E User's Guide 5-3