When Field - HP 1660CS-Series User Manual

The Scope Trigger Menu

When field

When field
The When field appears only when Pattern mode is selected. When you
select this field, a pop-up menu appears that lets you specify the trigger
When condition.
Pattern When condition pop-up menu
The Pattern When pop-up menu is used to specify the trigger-when condition
for pattern triggering. The default selection for the When field is When
Entered.
When Entered When this field is active, the oscilloscope triggers on the
first transition that makes the pattern specification true for every input
used in the pattern trigger specification. If the count set in the Count
field is more than 1, the pattern must be true for the number of times set
in the count field.
When Exited When this field is active, the oscilloscope triggers on the
first transition that causes the pattern specification to be false for every
input used in the pattern trigger specification. If the count set in the
Count field is more than 1, the pattern must be true for the number of
times set in the count field before turning false.
Present > When this field is active, the scope triggers on the first
transition that causes the pattern specification to be false for any input
used in the pattern trigger specification if the specified pattern has been
true for the time duration specified. If the pattern specification becomes
false before the specified duration time has elapsed, the search for a
trigger condition starts again. If the pattern specification remains true
longer than the specified duration time, the trigger point will be the point
at which the pattern specification becomes false.
The pattern duration time can be any value between 20 ns and 160 ms in
10 ns steps.
If the count set in the Count field is one, the trigger event will be the first
pattern event that meets both the pattern specification and the duration
specification. If the count is greater than one, only the first pattern event
must meet the duration specification. Once the pattern duration
specification has been met, subsequent pattern events that meet the pattern
specification can be of any duration and each such pattern event will
contribute to meeting the count specification. For instance, with a pattern
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