HP 54620A, Руководство пользователя и сервисное руководство

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Period is calculated by selecting
the first and third transitions from
the left side of the visible display and
measuring the delta time between
these two transitions.
Positive width is the time of a sig-
nal or glitch that is high.
Pixel memory See “Display mem-
ory.”
Print copies the current display to
the attached printer. You must have
either an HP-IB, RS-232, or Centron-
ics/parallel Interface module to use
the print capability.
RUN indicator is displayed at the
right end of the status line when the
acquisition is running.
Sample period is the interval at
which the input is sampled. The ana-
lyzer acquires data by sampling the
voltage on each input channel and
comparing it to the threshold voltage
to determine whether the input was
a logic high or logic low. The acquisi-
tion mode, trigger functions, delayed
sweep, and measurement functions
depend on the sample period. The
sample period, in turn, depends on
the Time/Div setting.
Setup memory allows you to save
the current configuration of the in-
strument, including time base,
threshold, channel settings, measure-
ment definitions, and labels. You can
use these later to verify the results
of a change, or you can use them
regularly for testing and trou-
bleshooting. These memories are
non-volatile.
Setup time is the time for which a
data input to a clocked device must
remain stable before the active edge
of the clock occurs. Violating the
setup time specification of a device
can lead to unstable circuit opera-
tion.
Signal inputs connect the logic
analyzer acquisition system to the
probes.
Single indicator is shown as the
letters “Sngl” in the display and indi-
cates that the current display was
captured by pressing the Single key
(a single acquisition was performed,
then the analyzer stopped).
Single-channel measurements
measure time between sets of events
on the same channel, then calculate
the appropriate values based on the
definition of the measurement. Meas-
urements include period, frequency,
duty cycle, positive width, and nega-
tive width.
Glossary
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