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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
<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
50 ns 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.
Range. When this field is active, the scope triggers on the first
transition that causes the pattern specification to be false for any input
used in the pattern trigger specification if the specified pattern has
been true for greater than the first time value and less than the second
time value that make up the pattern duration range.
If the pattern specification remains true for longer than the maximum
duration range limit or becomes false before the minimum duration
range limit, the search for a trigger condition starts again the next time
the pattern specification becomes true. If the pattern specification
becomes false within the specified duration time range, the trigger
point will be the point at which the pattern specification becomes false.
The minimum pattern duration time can be any value between 20 ns
and 160 ms in 10 ns steps. The maximum pattern duration time must
be at least 10 ns greater than the minimum time value.