Trigger Types - Teledyne HDO9000 Operator's Manual

Trigger Types

The Trigger Type sets the triggering conditions. Special MultiStage types allow one set of conditions
for arming and another (same or different) set for triggering.
If a type is part of a subgroup (e.g., Smart), first choose the subgroup to display all the trigger options.
Basic Types
Edge triggers upon a achieving a certain voltage level in the positive or negative slope of the
waveform.
Width triggers upon finding a positive- or negative-going pulse width when measured at the specified
voltage level.
Pattern triggers upon a user-defined pattern of concurrent high and low voltage levels on selected
inputs. In Mixed-Signal oscilloscopes, it may be a digital logic pattern relative to voltage levels on
analog channels, or just a digital logic pattern omitting any analog inputs. Likewise, if your
oscilloscope does not have Mixed-Signal capability, the pattern can be set using analog channels
alone.
TV triggers on a specified line and field in standard (PAL, SECAM, NTSC, HDTV) or custom composite
video signals.
Serial triggers on the occurrence of user-defined serial data events. This type will only appear if you
have installed protocol-specific serial data trigger and decode options.
Measurement is not technically a trigger, per se, but permits the instrument to stop and display
acquisition based on a post-processing measurement result, similar to a trigger.
MultiStage Types
MultiStage subgroup triggers establish dependencies between two or more distinct events, some that
"qualify" or arm, and others that trigger. The individual events are defined exactly as are the basic
types (Edge, Width, Pattern, etc.).
Cascaded establishes a succession of criteria in Stages A-D. The trigger occurs when stages B
through D—or whatever is the last defined event—are achieved. In Normal trigger mode, it
automatically resets after finding the last defined event. You may apply additional Holdoff by time or
number of events between each stage in the cascade.
QualFirst arms the oscilloscope on the A event, then triggers on all subsequent B events, saving each
as a Sequence Mode segment.
Note: This trigger is only enabled when using Sequence sampling mode.
Qualified arms on the A event, then triggers on the B event. In Normal trigger mode, it automatically
resets after the B event, and re-arms upon the next matching A event.
Note: This functionality is identical to Teledyne LeCroy's previous Qualify and State triggers,
but presented through a different user interface.
Acquisition
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