HP 54620A, User'S And Service Manual

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the analyzer to recognize it as match-
ing a pattern trigger specification.
At very fast sweep speeds (small
Time/Div settings), the pattern
width is nearly a constant value. At
time base settings of 2
µ
s/div and
slower, this is approximately a con-
stant value plus one sample period.
Minimum duration trigger setting
specifies the shortest duration set-
ting that the analyzer can accurately
verify against the incoming pattern.
The minimum duration trigger set-
ting is two sample periods or 16 ns,
whichever is greater.
Negative width is the time for
which a signal is low.
Normal trigger mode causes the
analyzer to begin filling the pre-trig-
ger buffer with data. When the
buffer is full, the analyzer will begin
searching for the trigger event.
When the trigger is event is found,
the analyzer fills the post-trigger
buffer and displays the acquisition
memory. Until the analyzer finds the
trigger, the acquisition will not be
displayed, and the analyzer will
search for the trigger indefinitely.
Occurrence trigger operator is
used to specify the number of times
an edge term or a pattern and edge
term combination occurs. Occur-
rence operators are available in ad-
vanced trigger mode, are valid only
when at least one edge term is in-
volved, and are not selectable when
only pattern terms are selected as a
source.
Palettes include colors that you
can assign to channels with the
HP 54620C color logic analyzer. Six
color palettes are available, and are
individually named so that you can
select the palette that best suits your
needs. In each palette, colors are
used for cursors, waveforms, soft-
keys, and Autostore. A monochrome
palette is also available.
Pan the display means the acqui-
sition moves horizontally on screen
when you rotate the Delay knob. Pan-
ning the display adjusts the amount
of time between the trigger event
and the time reference point on the
display.
Pattern trigger defines a set of
pattern of highs, lows, and don’t care
inputs that must be recognized
across the input channels during any
given input sample. The pattern may
be combined with one edge on any
input channel to form the complete
trigger specification. The pattern
trigger occurs when the pattern is en-
tered.
Glossary
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