Keithley 6430, Instruction Manual

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16-4 SCPI Signal-Oriented Measurement Commands
[:SENSe[1]]:DATA[:LATest]?
Description
This command works exactly like FETCh?, except that it returns only the
most recent reading.
:READ?
Description
This command is used to trigger and acquire readings. The number of read-
ings depends on how the trigger model is con
fi gured. For example, if con-
fi gured for 20 source-measure operations (arm count 1, trigger count 20),
then 20 sets of readings will be acquired after the SourceMeter returns to the
idle state.
When this command is sent, the following commands execute in the order
that they are presented:
• :INITiate
• :FETCh?
The :INITiate command starts operation by taking the instrument out of
idle.
After all source-measure operations are completed, the SourceMeter goes
back into idle at which time the :FETCh? command is executed. The read-
ings are sent to the computer and displayed when the SourceMeter is
addressed to talk.
Note that if auto output-off is disabled (:SOURce1:CLEar:AUTO OFF),
then the output must be turned on before you can perform a :READ?. The
output will then remain on after all source-measure operations are
completed.
If auto output-off is enabled (:SOURce1:CLEar:AUTO ON), then the output
will automatically turn on at the beginning of each SDM (source-delay-
measure) cycle and turn off after each measurement.
NOTE
See Appendix C for a detailed explanation on how data flows through the various
operation blocks of the SourceMeter. It clarifies the type of readings that are
acquired by the various commands to read data.