Chapter 4 Command Reference

[:SENSe] Subsystem

[:SENSe]:PHASe:ARM[:STARt]:SOURce IMMediate EXTernal

Sets or queries the start arm for Phase measurements.

Query Response A sequence of ASCII-encoded bytes: IMM or EXT

Comments *RST: IMMediate

Related Gate & ExtArm

Front-Panel

Keys

[:SENSe]:ROSCillator Subtree

This subtree controls the Reference Oscillator .

[:SENSe]:ROSCillator:EXTernal:CHECk ON OFF ONCE

Sets or queries the enable for “checking” the validity and presence of the external reference.

When CHECk is ON and external has been explicitly selected ([:SENS]:ROSC:SOUR is EXT and [:SENS]:ROSC:SOUR:AUTO is OFF), the Counter checks the external reference signal to ensure that the frequency is 1, 5, or 10 MHz and that the reference is present at measurement completion. Note that the HP 53132A only accepts 10 MHz. When CHECk is OFF, the external reference signal is not checked at all.

CHECk ONCE is an event which invokes the external reference check at the time the command is executed. ONCE is only permitted if [:SENS]:ROSC:SOUR is EXT; otherwise, error -221 is generated.

If the CHECk ONCE does not detect a valid timebase, error +2009 is generated. After the check is completed, this command’s parameter is set to OFF.

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Programming Guide