Keithley 2750, Руководство пользователя

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Model 2750 Multimeter/Switch System User’s Manual Remote Operations 10-9
DCL (device clear)
Use the DCL command to clear the GPIB interface and return it to a known state. Note
that the DCL command is not an addressed command, so all instruments equipped to
implement DCL will do so simultaneously.
When the Model 2750 receives a DCL command, it clears the Input Buffer and Output
Queue, cancels deferred commands, and clears any command that prevents the processing
of any other device command. A DCL does not affect instrument settings and stored data.
SDC (selective device clear)
The SDC command is an addressed command that performs essentially the same function
as the DCL command. However, since each device must be individually addressed, the
SDC command provides a method to clear only selected instruments instead of clearing all
instruments simultaneously, as is the case with DCL.
GET (group execute trigger)
GET is a GPIB trigger that is used as a trigger event to control operation. The Model 2750
reacts to this trigger if it is the programmed trigger control source. The following com-
mand selects the GPIB trigger control source:
TRIGger:SOURce BUS
When a GPIB trigger is sent to the Model 2750, operation will continue in the trigger
model. See
Section 8 for details on triggering.
SPE, SPD (serial polling)
Use the serial polling sequence to obtain the Model 2750 serial poll byte. The serial poll
byte contains important information about internal functions. (See
Section 11 , “ Status
Structure .”) Generally, the serial polling sequence is used by the controller to determine
which of several instruments has requested service with the SRQ line. However, the serial
polling sequence may be performed at any time to obtain the status byte from the Model
2750.
2750-900-01.book Page 9 Wednesday, August 3, 2011 7:56 AM