HP 53181A Programming Manual page 225

Commands Reference
Measurement Instructions (:CONFigure, :FETCh, :MEASure, :READ)
How to Use the Measurement Instruction Commands (Cont.)
Use
:SENS:EVEN:LEV 0V
to set the trigger level to 0 Volts.
Use
:INITIATE
to start the measurement.
Use
:FETCH?
to query for result.
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