Chapter 5 To Trigger the Oscilloscope RIGOL
MSO1000Z/DS1000Z User’s Guide 5-3
Trigger Mode
Trigger mode affects the way in which the oscilloscope searches for a trigger. The
following is the schematic diagram of the acquisition memory. As shown in the figure
below, the position of the trigger event is determined by the reference time point and
the delay setting.
Note: The acquisition memory of the oscilloscope is a cyclic buffer and the new data
would overwrite the old data until the acquisition finishes.
Figure 5-1 Schematic Diagram of the Acquisition Memory
Pre-trigger/Delayed trigger:
Acquire data before/after the trigger event. The trigger position is usually at the
horizontal center of the screen. In full-screen display, six-grid pre-trigger and delayed
trigger information are displayed respectively. You can adjust the horizontal position
of the waveform through HORIZONTAL
POSITION to view more pre-trigger
information or delayed trigger information, through which the signal information
before/after the trigger (such as capture the glitch generated by the circuit and
analyze the pre-trigger data to find out the reasons for glitch) can be obtained.
Press MODE in the trigger control area (TRIGGER) at 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:
After this mode is selected, the oscilloscope starts searching for trigger signals that
meet the specified condition. If trigger signals that meets the specified condition are
found, “T’D” is displayed at the upper-left corner of the user interface and stable
waveform is displayed. Otherwise, “AUTO” is displayed and unstable waveform is
displayed.
Note: When the horizontal time base setting is 50 ms/div or greater, you can also
observe the input waveform without a trigger signal in this mode.
Normal:
After this mode is selected, the oscilloscope enters the wait-for-trigger state and
starts searching for trigger signals that meet the specified condition. If trigger signals
that meets the specified condition are found, “T’D” is displayed in the running status