Chapter 6: Concepts

Understanding Logic Analyzer Triggering

“not in range” function as well. Ranges are a convenient shortcut so that you don't have to specify “ADDR >= 1000 and ADDR <= 2000”.

Next: “Flags” on page 247

Flags

Flags are Boolean variables that are used to send signals from one module to another. They can be set when a condition occurs in one module and tested later by another module. In the example below, flag 1 is used to keep track of what happens in the trigger sequence of Module 1 so that this information can be used in Module 2.

Trigger Sequence for Module 1

1.If ADDR < 5000 then Set Flag 1

Trigger and fill memory

Trigger Sequence for Module 2

1.If DATA = 5000 and Flag 1 is set then Trigger Else if DATA = 1000 and not Flag 1 then Trigger

Next: “Occurrence Counters and Global Counters” on page 247

Occurrence Counters and Global Counters

Occurrence Counters are used in situations where you want to find the Nth occurrence of an event. For example, if you want to trigger on the 5th time that ADDR = 1000, you could set up the trigger as:

If ADDR = 1000 occurs 5 times then Trigger

Global Counters are like integer variables. They are more flexible than Occurrence Counters because they can be used to count complex events such as an edge followed by another edge. Global Counters can be incremented, tested, and reset. By default, Global Counters begin with zero and don't need to be reset unless they have already been used in the trigger sequence. In general, Occurrence Counters should

247

Page 247
Image 247
Agilent Technologies 16760A manual Occurrence Counters and Global Counters, Next Flags on, Trigger Sequence for Module