HP 64782, Руководство пользователя, Страница: 196 / 554

The Basics of Starting, Stopping, and
Displaying Traces
This section describes the basic tasks that relate to starting and stopping
trace measurements.
When you start a trace measurement, the analyzer begins looking at the data
on the emulation processor’s bus and control signals on each analyzer clock
signal. The information seen on a particular clock is called a state.
When one of these states matches the "trigger state" you specify, the analyzer
stores states in trace memory. When trace memory is filled, the trace is said
to be "complete." The default trigger state specification is "any state," so
when you start a trace measurement after initializing the analyzer, the
analyzer will "trigger" on the first state it sees and store the following states
in trace memory.
Once you start a trace measurement, you can view the progress of the
measurement by displaying the trace status.
In some situations, for example, when the trigger state is never found or
when the analyzer hasn’t filled trace memory, the trace measurement does
not complete. In these situations, you can halt the trace measurement.
Once a trace is displayed, you can use the cursor keys and other keys to
position the trace list on the display. To speed up the display of traces, you
can reduce the depth of the trace list. Also, when entering trace commands,
there is a special command that allows you to recall and modify the last trace
command entered.
This section describes how to:
•
Start a trace measurement.
•
Display the trace list.
•
Display the trace status.
•
Change the trace depth.
•
Modify the last trace command entered.
•
Repeat the previous trace command.
•
Position the trace display on the screen.
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