Agilent Technologies A.18.00 Device Clear (DCL) GPIB Bus Command

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Chapter 5, Advanced Operations
Instrument Initialization
Device Clear (DCL) GPIB Bus Command
The Device Clear (DCL) Reset is accomplished by sending the DCL message to
the Test Set through the GPIB bus.
The DCL command clears the Input Buffer and Output Queue, clears any
commands in process, puts the Test Set into the Operation Complete idle state,
and prepares the Test Set to receive new comman ds. The DCL bus c ommand d oes
not change any settings or stored data (except as noted previously), interrupt fro nt
panel I/O, interrupt any Test Set operation in progress (except as noted
previously), or change the contents of the Status Byte Register (other than
clearing the MAV bit as a consequence of clearing the Output Queue).
The DCL bus command has no effect on the I/O CONFIGURE, CONFIGURE,
PRINT CONFIGURE, or TESTS (Main Menu, Execution Conditions, External
Devices, Printer Setup) screens.
Other operational characteristics are also affected by the DCL bus command as
follows:
• The Power-up self-test diagnostics are not performed.
• The GPIB interface is not reset (any pending Service Request is not cleared)
• Measurement triggering is not affected.
• Calibration data is not affected.
• The Contents of the SAVE/RECALL registers are not affected.
• All Enable registers are unaffected: Service Request, Standard Event, Hardware #1,
Hardware #2, Operation, Calibration,Call Processing and Questionable Data/Signal.
• All Negative Transition Filter registers are unaffected: Hardware #1, Hardware #2, Op-
eration, Calibration,Call Processing and Questionable Data/Signal.
• All Positive Transition Filter registers are unaffected: Hardware #1, Hardware #2, Op-
eration, Calibration,Call Processing and Questionable Data/Signal.
• The contents of the RAM memory are unaffected.
• The contents of the Error Queue are unaffected.
• The state of the Test Set’s display screen is unaffected.