LeCroy USB Protocol Suite Advisor T3, Руководство пользователя

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USB Protocol Suite User Manual Chapter 10: Recording Options
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10.6.9 Counters and Timers for USB 3.0
Timer: A timer counts the time from a starting event to a final event. For example, if you
enter 10 , the Analyzer counts 10 nanoseconds or milliseconds after the starting event
before it performs whatever action you assign. Timers cannot be applied to events with
Filter Actions. The maximum timer value is 65,535.
Counter: A counter tells the Analyzer to search for x instances of the selected event. For
example, if you enter 10 , the Analyzer counts 10 instances of the selected event before
it performs whatever action you assign. Counters cannot be applied to events with Filter
Actions. The maximum counter value is 65,535.
Triggers can be set on multiple instances of an event. For example, you can set a trigger
to occur following five instances of any DLP. To configure the Analyzer to look for multiple
events, you enable Counters. Counters tell the Analyzer how many occurrences of an
event for which it should wait before triggering. For example, use a counter to Trigger
following the 16th occurrence of an error or DLLP message.
Events and Actions
Within events, counters determine how many times the event must occur before the
associated actions are triggered. Event counters typically have two properties:
• Count Randomly : Can be set to “Yes” or “No” (default value is “No”). If set to “Yes”,
the event repeats a random number of times (between 1 and the value set in the
property Max Random Count, which replaces the property Counter Value when
“Yes” is selected), before the action is triggered.
• Counter Value : Number of repeats required when Count Randomly is set to “No”.
The default value is 1.
Within actions, counters determine how many times the system calls the action before it
acts. Action counters typically have two properties:
• Random : Can be set to “Yes” or “No” (default value is “No”). If set to “Yes”, the
action triggers a number of occurrences before the action takes place. That number
ranges randomly between 1 and the value set in the property At least every Nth
occurrence, which replaces the property Every Nth occurrence when “Yes” is
selected.
• Every Nth occurrence : Number of times the system calls the action before it acts.
Note that there is some overlap in the way these counters can be used. For example, in
the simple case of a single event leading to a single action, it makes no difference
whether you specify the event to require five repeats before triggering the action, or the
action to require five occurrences before it acts.
However, in the case of combined events and/or actions, the separate counters provide
flexibility in designing test cases. For example, consider the case where Event_1 OR
Event_2 leads to Action. If Event_1 has a counter of 5, then the Action triggers either
when Event_1 has repeated five times or when Event_2 happens the first time,
whichever occurs first.
But if the event counters are set to 1 and the Action counter is set to 5, then the Action
happens after five occurrences of EITHER Event_1 or Event_2.
Number of Analyzer Counters and Timers
The Analyzer includes one event counter and one time counter (timer). If you try to assign
more, you get a warning.