Racal Instruments 3151, User Manual

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3151 And 3151A User Manual
Using The Instrument 3-20
remains at a certain DC level as long as the TRIG IN signal from the
front panel remains inactive. A TTL level signal is used to stimulate
the TRIG input. The gating signal can be programmed to be either
active high or active low. Each time the proper level is present at the
trigger input connector, the Model 3151/3151A generates output
waveforms as long as the gate signal is present. When the gate
signal is de-asserted, the output completes the last cycle and
resumes position at a DC level equal to the last point of the
waveform.
Gated mode operates on standard waveforms, arbitrary waveforms,
and on sequences of waveforms. Observe the limitations of the
gating signal as listed in the specification section of this manual. To
place the Model 3151/3151A in Gated mode, use the following
commands:
INIT:CONT OFF
TRIGger:GATE {OFF | ON}
The default state for the Gated mode is OFF. Turning Gated mode
ON automatically turns Burst mode off.
The query:
TRIGger:GATE?
queries the gate state and returns "0" (OFF) or "1" (ON).
Burst Mode
Burst mode is very similar to Triggered mode with the exception that
only one trigger signal is needed to generate a counted number of
output waveforms. In Burst mode, the output remains at a certain DC
level as long as the TRIG IN signal from the front panel remains
inactive. A TTL signal is used to stimulate the TRIG input. The
generator is sensitive to either the rising edge or the falling edge.
Each time a transition at the trigger input occurs, the Model
3151/3151A generates a number of output cycles that have been
programmed in the burst count parameter. At the end of the burst,
the output resumes position at a DC level equal to the last point of
the waveform. The burst count is programmable from 1 to 10
6
. The
default burst value is 1.
The Burst mode operates on standard waveforms and arbitrary
waveforms. Note that the Model 3151/3151A cannot operate in
Sequence and Burst modes simultanously. Observe the limitations of
the trigger signal as listed in the specification section of this manual.
To place the Model 3151/3151A in Burst mode, use the following
commands:
INITitiate:CONTinuous OFF
TRIGger:BURSt ON