Chapter 6: Concepts

Understanding Logic Analyzer Triggering

“Find Edge” and “Find Pattern” together

Next: “Setting Up Complex Triggers” on page 254

Setting Up Complex Triggers

Frequently, the most difficult part of setting up a complex trigger is breaking down the problem. In other words, how do you map a complex trigger into sequence levels, branches, and Boolean expressions? Here are step by step instructions:

1.Break down the problem into events that don't happen simultaneously. These correspond to the sequence levels.

2.Scan the list of trigger functions to try to find some that match the events identified in Step #1.

3.Within all remaining events, break them down into Boolean expressions and their corresponding actions. Each Boolean expression/Action pair corresponds to a separate branch within a sequence level. Remember that “Store” branches may exist that are used only to handle storage qualification for that sequence level.

Next: “Document Your Trigger Sequences” on page 254

Document Your Trigger Sequences

If a trigger sequence is important at one time, it is likely to be important again. This is why documenting trigger sequences is so valuable. Complex trigger sequences generally are too difficult to understand without some accompanying explanation. The following figure shows an example of the inline documentation on an Agilent Technologies logic analyzer. Inline means that the documentation is included in the trigger definition itself. This allows you to document

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Agilent Technologies 16760A manual Setting Up Complex Triggers, Document Your Trigger Sequences