Keysight Technologies 3458A Guide D'utilisation page 485

Capturing the Data
The 3458A can be triggered to commence the measurement cycle by the level and
slope of the input signal, by a zero voltage level crossing of the power line, by the
GET (group execute trigger) command on the GPIB, by an external TTL signal, by
an internally generated trigger signal (for burst measurements, this can be
paced), and by the computer asking for a reading.
The 3458A provides all the tools you need to catch the signal of interest by
offering three levels of triggering and up to eight conditions to satisfy including
the wave form's level and slope. The hierarchy of trigger levels is trigger arming
(TARM), trigger (TRIG), and number of readings per trigger (NRDGS). Focused at
digitizing, two additional commands are used for direct sampling and
subsampling: SWEEP which is related to NRDGS, and SSRC which selects the
trigger source (level or external) for subsampling. You can choose from a variety of
events or conditions that must be satisfied before taking measurements, as shown
is
3458A will generate its own trigger as fast as the multimeter set-up allows.
Figure E-5
TARM is the first condition to be satisfied. Its function is to arm the trigger circuit
prior to receiving the trigger signal. For example, if a synchronizing signal were
available external to the signal of interest, then TARM EXT could be used to arm
the 3458A to look for the trigger event. Also, TARM can be used to control
multiple measurement sequences by adding the number of times you want a
particular measurement cycle repeated. For example, TARM SGL,4, specifies that
the trigger arming be applied four times and then stops. Refer to
Keysight 3458A User's Guide
Figure E-5. The default condition for all three levels of triggering is AUTO; the
The trigger event choices shown provide the versatility needed
to match a wide variety of applications.
High Resolution Digitizing With the 3458A E
Figure E-6.
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