Tektronix, Inc. P6240, Руководство пользователя

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Triggering
2–14
TLS 216 User Manual
Input channels provide the most commonly used trigger source. The trigger
source can be any one of the 16 input channels. The channel you select as a
trigger source will function whether it is displayed or not, or whether it belongs
to a waveform group or not.
AC Line Voltage is the trigger source most often used when you are looking at
signals related to the power line frequency. Examples include devices such as
lighting equipment and power supplies. Because the logic scope generates the
trigger, you do not have to input a signal to create it.
Auxiliary Trigger is the trigger source most often used in digital design and
repair. For example, you might want to trigger with an external clock or with a
signal from another part of the circuit. To use the auxiliary trigger, connect the
external triggering signal to the Auxiliary Trigger input connector on the logic
scope rear panel.
Types
The logic scope includes five standard trigger types in both the main and the
delay trigger systems. All five types are described in individual articles found in
the Section 3 Reference. A brief definition of each type follows:
Edge is the “basic” or general-purpose trigger. You can use it with both analog
and digital test circuits. An edge trigger event occurs when the trigger source (the
signal the trigger circuit is monitoring) passes through a specified voltage level
in the specified direction (the trigger slope).
Pulse is a special-purpose trigger primarily used on digital circuits. Two classes
of pulse triggers are width and glitch. Triggering occurs when time constraints
you specify on pulse or glitch width are satisfied.
Pattern is a special-purpose trigger primarily used on digital logic circuits. You
select Boolean operators and define logic levels for the trigger sources. Trigger-
ing occurs when the Boolean conditions are satisfied relative to a time limit or
time range you specify.
State is a special-purpose trigger primarily used on digital logic circuits. Like
pattern trigger, you select Boolean operators and define logic levels for trigger
sources. Triggering occurs when the Boolean conditions are satisfied at the active
edge of the clock.
Sequence is a special-purpose trigger primarily used on digital logic circuits.
Like pattern trigger, you select Boolean operators and define logic levels for
trigger sources, but you do so for two events, a start event and a stop event.
Triggering occurs when the Boolean conditions are first satisfied, for the start
event and then for the end event, relative to a time limit or time range you
specify.