Tektronix, Inc. P6240, Руководство пользователя

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Triggering on Pulses
TLS 216 User Manual
3–145
Glitch Negative looks at negative-going pulses.
You can specify whether to trigger on glitches or filter out (ignore) glitches by
specifying the glitch width and setting a time qualifier. To ignore glitches shorter
than a time you specify:
1. Press TRIGGER MENU
➞
Type (main)
➞
Pulse (pop-up)
➞
Trig When
(main)
➞
Width (side).
2. Turn the general purpose knob or use the keypad to enter a width for glitches
that are to be ignored.
3. Press > Time. Glitches will have to be wider than the time set in step 2 to
cause the logic scope to trigger. Any glitch wide enough to trigger the logic
scope triggers it at the trailing edge of the glitch.
4. Readjust the trigger threshold as needed. (See procedure on page 3–144.)
To trigger on, rather than ignore, glitches that are narrower than a time you
specify, press < Time instead of > Time in step 3, above. Any glitch narrow
enough to trigger the logic scope triggers it at the trailing edge of the glitch.
To trigger on a glitch at the point it exceeds a width you specify, press Time Out
instead of > Time in step 3, above. Any glitch wide enough to trigger the logic
scope triggers it at the point the glitch width exceeds the time you set.
To Trigger Based on Pulse Width
To trigger on a pulse narrower (or wider) than some specified range of pulse
widths (defined by the upper limit and lower limit), do the following procedures.
To select pulse width triggering, do the following steps.
1. Press TRIGGER MENU
➞
Type (main)
➞
Pulse (pop-up)
➞
Class
(main)
➞
Width (side).
2. Press Polarity (main)
➞
Positive or Negative (side).
Pulse Width Positive looks at positive-going pulses.
Pulse Width Negative looks at negative-going pulses.
Time Qualify the Glitch
Select Pulse Triggering
and Pulse Polarity