Tektronix, Inc. P6240, User Manual

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Triggering on Patterns
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TLS 216 User Manual
4. The logic scope keeps time to make sure the pattern remains TRUE for a
time you specify.
5. When the pattern satisfies the time qualification, the logic scope triggers.
Table 3–7 lists each time qualifier versus the trigger event it qualifies.
Table 3–7: Time Qualifiers
Trig When Time Qualifiers versus Trigger Event
< Time The inputs must be TRUE
1,2
for a period that ends before a user-specified
time expires.
The logic scope triggers at the point that the inputs go FALSE.
> Time The inputs must be TRUE for a period that ends after a user-specified time
expires.
The logic scope triggers at the point that inputs go FALSE.
Time Out The inputs must stay TRUE for a period that continues after a user-specified
time expires.
The logic scope triggers at the point that time expires.
In Range The inputs must stay TRUE for a period that ends after a user-specified
minimum time but before a user-specified maximum time expires.
The logic scope triggers at the point that the inputs go FALSE.
Out of Range The inputs must stay TRUE for a period that ends before a user-specified
minimum time or after a user-specified maximum time expires.
The logic scope triggers at the point that the inputs go FALSE.
1
Inputs are TRUE when they meet the Boolean requirement for the logic function selected;
otherwise they are FALSE. See Table 3–6.
2
The logic scope starts timing the period at the point when the inputs become TRUE. (See
footnote 1.)
As Table 3–7 indicates, the time qualifier you choose determines the trigger
point. Depending on the time qualifier you choose, you can:
H
trigger as soon as possible after the logic scope recognizes your pattern.
H
trigger after the logic scope recognizes your pattern for a time you specify.
The two ways of triggering just listed reflect the following key concepts
governing pattern triggering with the logic scope.
H
The trigger event does not occur when the inputs first meet Boolean
requirements (input pattern compares TRUE). Rather, the logic scope starts a
timer it uses to determine if the pattern satisfies the time qualification set.
How Time Qualification
Affects the Trigger Point