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Using the Oscilloscope
The Scope Trigger Menu
If the count set in the Count field is one, the trigger event will be the
first pattern event that meets both the pattern specification and the
duration specification. If the count is greater than one, only the first
pattern event must meet the duration specification. Once the pattern
duration specification has been met, subsequent pattern events that
meet the pattern specification can be of any duration and each such
pattern event will contribute to meeting the count specification. For
instance, with a pattern specification of HX, a duration specification of
>60 ns & <100 ns, and a count of 3, a pulse string with pulse widths 200
ns, 80 ns, 150 ns, 50 ns, 75 ns, 20 ns would trigger on the trailing edge
of the 50ns pulse. In this example, the 80 ns pulse meets the duration
specification and is count 1, the 150 ns pulse is count 2, and the 50 ns
pulse is count 3.
Count field
In pattern trigger mode, you can define a pattern as a trigger qualifier.
When the oscilloscope detects the trigger qualifier, it will trigger when
the number of patterns specified in the Count field have occurred on all
inputs.
The Count field defines the number of events that must occur after the
first trigger qualifier before the oscilloscope will trigger and acquire a
waveform.
Count can be set to any integer from 1 to 32,000. The default value for
the Count field is 1.