Section 2: General operation
Model 2651A High Power System SourceMeter® Instrument Reference Manual
2-78
2651A-901-01 Rev. A / March 2011
Connect any additional connectors from other instruments as required for your application. Make sure
the other end of the cable is properly connected to the controller. You can only have 15 devices
connected to an IEEE-488 bus, including the controller. The maximum cable length is either 20
meters or two meters multiplied by the number of devices, whichever is less. Not observing these
limits may cause erratic bus operation.
Primary address
The Model 2651A ships from the factory with a GPIB primary address of 26. If the GPIB interface is
enabled, it momentarily displays the primary address on power-up. You can set the address to a
value from 0 to 30, but do not assign the same address to another device or to a controller that is on
the same GPIB bus (controller addresses are usually 0 or 21).
Front panel primary address
To set or check the primary address:
1. Press
the
MENU
key, then select
GPIB
, and then press the
ENTER
key or the navigation wheel
.
2. Turn the navigation wheel
to set the primary address to the desired value, then press the
ENTER
key or the navigation wheel
.
3. Press
the
EXIT (LOCAL)
key to back out of the menu structure.
Remote primary address
Use the following command to set the primary address by remote:
gpib.address = address
To remotely set the primary address to 20, send:
gpib.address = 20
Note that changing the GPIB address takes effect when the command is processed. Any response
messages generated after processing this command will be sent with the new settings. If command
messages are being queued (sent before this command has executed), the new settings may take
effect in the middle of a subsequent command message, so care should be exercised when setting
this attribute from the GPIB interface.
Terminator
When receiving data over the GPIB, the instrument terminates messages on any line feed character
or any data byte with EOI asserted (line feed with EOI asserted is also valid). When sending data, it
appends a line feed character to all outgoing messages. The EOI line is asserted with the terminating
line feed character.
General bus commands
General commands are commands that have the same general meaning regardless of the instrument
(for example, DCL). The following table lists the general bus commands.