Tektronix 6 series, Printable Help

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CAN. Use to trigger on CAN Bus signals.
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LIN. Use to trigger on LIN bus signals.
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FlexRay. Use to trigger on FlexRay bus signals.
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USB. Use to trigger on USB bus signals.
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Ethernet. Use to trigger on Ethernet bus signals.
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Audio. Use to trigger on Audio bus signals.
Trigger modes
The trigger mode determines how the instrument behaves in the absence of a trigger event:
■ Normal trigger mode enables the instrument to acquire a waveform only when it is triggered. If no trigger occurs, the
instrument does not acquire a waveform, and the last waveform record acquired remains "frozen" on the display. If no last
waveform exists, no waveform is displayed.
■ Auto trigger mode enables the instrument to acquire a waveform even if a trigger does not occur. Auto mode uses a timer
that starts after a trigger event occurs. If another trigger event is not detected before the time out, the instrument forces a
trigger. The length of time it waits for a trigger event depends on the time base setting.
Auto mode, when forcing triggers in the absence of valid triggering events, does not synchronize the waveform on the display. In
other words, successive acquisitions are not triggered at the same point on the waveform; therefore, the waveform will appear to
roll across the screen. If valid triggers occur, the display will become stable.
Trigger holdoff
Trigger holdoff can help stabilize triggering. When the instrument recognizes a trigger event, it disables the trigger system until
acquisition is complete. In addition, the trigger system remains disabled during the holdoff period that follows each acquisition.
Adjust holdoff to obtain stable triggering when the instrument is triggering on undesired trigger events.
A digital pulse train is a good example of a complex waveform. Each pulse looks like any other, so many possible trigger points
exist. Not all of these will result in the same display. The holdoff period allows the instrument to trigger on the correct edge,
resulting in a stable display.
At the longer holdoff time for the top waveform, unstable triggering occurs. With a shorter holdoff set for the bottom waveform,
triggers all occur on the first pulse in the burst to remedy the unstable trigger.
Trigger concepts
MSO54, MSO56, MSO58, MSO58LP, MSO64 Help 421