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Note: the 2560 Series oscilloscopes allow the use of either voltage or current units for waveform
measurements. The remainder of this chapter will refer to just voltages, but it applies to current
levels, too.
5.2
Auto Setup
The oscilloscope automatically identifies the waveform type, trigger level, and scales to produce
a usable display of the input signal.
Press the Auto Setup button to perform the function and the following softkeys will be available.
Softkey
Description
Multiple cycles
Shows multiple cycles. This is the default behavior.
One cycle
Shows one cycle of the waveform.
Rising edge
Puts a rising edge at the center of the screen by changing the
trigger slope to positive.
Falling edge
Puts a falling edge at the center of the screen by changing the
trigger slope to negative.
Restore previous settings
Go back to your previous settings. This acts like an undo button.
Noisy sine wave
Changes to averaging mode with a sample size of 16 to reduce
noise.
If the waveform is out of the Auto Setup's range, a dialog window will is displayed explaining that
Auto Setup did not work.
5.3
Setting the Trigger
Digital oscilloscopes capture the waveform continuously, but will not display the captured
waveform unless the oscilloscope is triggered. A stable display needs a stable trigger. The
triggering circuitry generates a trigger event when the logical trigger conditions are satisfied by
the waveform.
Here is a schematic diagram of the acquisition memory. The position of the trigger event in time
is defined to be the zero-time location. Waveform samples before the trigger event are in the
pre-trigger buffer and samples after the trigger event are in the post-trigger buffer. By default,
the trigger event is shown at the center of the screen, but turning the horizontal position knob
lets you put other portions of the buffer in the center of the screen.