HP 64783A, Руководство пользователя

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Making Simple Trace Measurements
You can make simple records of the processor’s bus activity using just a few
analyzer commands. When you set up the analyzer to record processor bus activity,
you are preparing to make a trace measurement. During the trace measurement, the
analyzer saves a record of the bus activity in trace memory. The display of the
trace memory content is called the trace list.
The information captured at the occurrence of each clock is called a state. When a
captured state matches your specification for the trigger state, the analyzer
identifies it as the trigger state and stores it in trace memory.
The default specification for the trigger state is "any state." When you start a trace
measurement using the default trace specification, the analyzer will identify the first
state it captures as the trigger state and fill the remaining space in the trace memory
with the states that follow it. A trace is said to be complete when the trace memory
is filled with captured states, and the trigger state resides at its specified point in the
trace memory (the first state captured in memory, by default).
When a trace measurement is started, 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 its 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 keyboard keys to
position the trace list on screen. To speed up the display of traces, you can reduce
the depth of the trace list. Also, when entering trace commands, you can recall and
modify preceding trace commands to speed command entry.
Chapter 5: Using the Emulation-Bus Analyzer
Making Simple Trace Measurements
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