HP 1660CS, User Manual

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The Scope Trigger Menu
The Scope Trigger menu allows you to choose the method you want to
use to trigger the oscilloscope for a particular application.
Trigger marker
The trigger marker is the dotted vertical line at the center of the waveform
display. The point where the waveform from the trigger source crosses the
trigger marker is called the trigger point. The trigger point always represents
a delay time of zero seconds.
If you set Delay time to greater than
±
5 times the the setting for s/Div, the
trigger marker will move off the screen.
Mode/Arm menu
The Mode/Arm field provides a pop-up menu with three types of triggering,
plus a fourth choice identical to the Arming Control field in the Analyzer
Trigger menu. The three types of triggering are Edge, Pattern, and
Immediate. For information on Arming Control, refer to "Arming Control
field" earlier in this chapter. Note that to time-correlate the oscilloscope and
the analyzer waveforms when the oscilloscope is armed by a logic analyzer,
the Mode must be set to Immediate.
Edge trigger mode
In the edge trigger mode, the oscilloscope triggers at a specified voltage level
on a rising or falling edge of one of the input channels. In this mode you can
specify which input is the trigger source, set a trigger level voltage, and
specify which edge to trigger on.
When you select edge trigger mode, additional fields appear for Source,
Level, Slope, Count, and Auto-Trig. These fields are discussed in the
following sections.
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