Model 2651A High Power System SourceMeter® Instrument Reference Manual
Section 2: General operation
2651A-901-01 Rev. A / March 2011
2-79
General bus commands
Command
Effect on Model 2651A
REN
Goes into remote when next addressed to listen.
IFC
Goes into talker and listener idle states.
LLO
LOCAL
key locked out.
GTL
Cancel remote; restore Model 2651A front panel operation.
DCL
Returns all devices to known conditions.
SDC
Returns Model 2651A to known conditions.
GET
Initiates a trigger.
SPE, SPD
Serial polls the Model 2651A.
REN
The remote enable command (REN) is sent to the Model 2651A by the controller to set up the
instrument for remote operation. Generally, the instrument should be placed in the remote mode
before you attempt to program it over the bus. Setting REN true does not place the instrument in the
remote state. You must address the instrument to listen after setting REN true before it goes into
remote.
IFC
The interface clear command (IFC) is sent by the controller to place the Model 2651A in the local,
talker, or listener idle states. The unit responds to the IFC command by cancelling front panel TALK
or LSTN lights, if the instrument was previously placed in one of these states.
Transfer of command messages to the instrument and transfer of response messages from the
instrument are not interrupted by IFC. If a response message was suspended by IFC, transfer of the
message will resume when the unit is addressed to talk. If a command message transfer was
suspended by IFC, the rest of the message can be sent when the unit is addressed to listen.
LLO
When the unit is in remote operation, all front-panel controls are disabled except the EXIT (LOCAL)
key and the OUTPUT ON/OFF control (and, of course, the POWER switch). The LLO command (local
lockout) disables the EXIT (LOCAL) key, but it does not affect the OUTPUT ON/OFF control, which
cannot be disabled.
GTL
Use the go to local command (GTL) to put a remote-mode instrument into local mode. Leaving the
remote state also restores operation of all front panel controls.