HP 1660CS, User Manual

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Modifying the user macro
Before you begin building a trigger specification using the user macro, it
should be noted that in most cases one of the pre-defined trigger macros will
work.
If you need to accommodate a specific trigger condition, or you prefer to
construct a trigger specification from scratch, use the User macro as a
starting point. This macro appears in long form, which means it has the
analyzer’s total flexibility available in terms of resource terms, global timers,
occurrence counters, duration counters, and two-way branching.
The User macro has a "fill-in-the-blanks" type statement. You have the
following elements to use:
•
Bit Patterns, Ranges, and Edges
•
Storage Qualification
•
< and > Durations
•
Occurrence Counters
•
Timers
•
Branching
A typical method used during a debug operation is to first trigger on a known
pattern, edge or range. From that point, it becomes an iterative process of
adding more levels to further filter the data. It is important for you to know
how to use such elements as occurrence counters, timers, and branching, to
zero in and trigger at the desired point.
As the analyzer executes the trigger specification, it searches for a match
between the resource term value and the data. When a match is found, that
part of the sequence statement becomes true and the sequencing continues
to the next part of the statement or the next sequence level.
Eventually a path of "true" resource terms leads to your trigger command. If
timers or occurrence counters are used, the analyzer waits or counts
occurrences of a specified value before continuing.
The following examples illustrate the use of resource terms, occurrence
counters, timers, branching, and store qualification. You will use them in
your trigger specification either by themselves or combined with each other.
The Analyzer Trigger Menu
Modifying the user macro
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