Tektronix, Inc. P6240, Руководство пользователя

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Triggering on a Sequence
TLS 216 User Manual
3–153
To change the holdoff time and select the trigger mode:
1. Press TRIGGER MENU
➞
Mode & Holdoff (main)
➞
Auto or Normal
(side).
In Auto mode the logic scope triggers an acquisition after a specific time has
elapsed even if a trigger event does not occur. The amount of time the logic
scope waits depends on the time base setting.
In Normal mode the logic scope acquires only if there is a valid trigger.
2. Press Holdoff (side). Enter the value in percent using the general purpose
knob or the keypad.
You can set the trigger threshold of each input individually to the same or
different levels. Also, you can set the trigger threshold of one input and copy it
to a group of inputs or to all inputs with one operation. To set the thresholds,
refer the general procedure To Set Trigger Thresholds on page 3–162.
NOTE . Although you can set the pattern logic levels (HIGH, LOW, and Don’t
Care) and pattern logic (AND, NAND, OR, and NOR) independently for the start
and end patterns, they must share the same trigger threshold levels. For
example, the threshold level you set for Ch1 is used for both patterns.
Also, when using sequence triggering with delayed acquisitions, see Trigger
Sources and Thresholds on page 3–122 for special considerations for setting
trigger thresholds.
To control how much time that a TRUE end pattern must trail a TRUE start
pattern in order for a trigger to occur, you must time qualify it. To do so, perform
one of the following procedures.
H
To trigger immediately when a TRUE end pattern follows a TRUE start
pattern, perform To Trigger Immediately on a Sequence below.
H
To trigger when a TRUE end pattern follows a TRUE start pattern within a
time less than or greater than a time limit that you specify, perform To
Trigger on a Time-Limit Qualified Sequence on page 3–155.
H
To trigger when a TRUE end pattern follows a TRUE start pattern within a
time that falls inside or outside a time range (window) that you specify,
perform To Trigger on a Time-Range Qualified Sequence on page 3–157.
Set Mode & Holdoff
Set the Trigger Thresholds
Qualify the Trigger