HP 54645A, Руководство пользователя и сервисное руководство

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5
Select the source(s) for the trigger operator by pressing the leftmost
Source
softkey until the desired source is highlighted.
Refer to the table of trigger operators and sources to see the sources and
operators with which they can be used.
The oscilloscope will allow you to choose combinations of sources that are
redundant, such as “Pattern 1 AND Pattern 1”, or combinations that will
create a null trigger condition, such as “Pattern 1 AND Not Pattern 1”.
6
Define the source pattern(s) by pressing the
Source Define
softkey.
If you combined patterns and edges in the same source term, you must
separately select each as the source, set up the source, then select the
combined pattern and edge again.
7
Set the parameters for the trigger operator, if necessary.
For the Duration operators (> time, < time, range), press/hold the duration
value softkey or rotate the Entry knob to set the duration.
Duration > time
When this operator is selected, you have two choices for trigger:
Trigger At: Timout (default) – trigger when > time criteria is met after you enter
the pattern. This is useful for conditions where the pattern occurs and you want
to see the waveform, but no edge follows immediately.
Trigger At: Pat Exit – trigger when you exit the pattern.
8
To set up an edge trigger source, do the following:
a
Select a channel for the source.
•
To choose whether the trigger will occur on the rising or falling edge,
press one of the
Edge Select
softkeys.
•
To set a channel to a don’t care trigger state, press the X softkey.
•
To clear all edge settings, press the
Clear Edge(s)
softkey.
In Edge1, you can select only one edge. You may select multiple edges
in Edge2; those edges are logically ORed.
b
Repeat step a for all channel sources you want to define.
c
Press
Previous Menu
to return to the Advanced Pattern Trigger menu.
Triggering HP 54645A/D Oscilloscopes
To define an advanced pattern trigger
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