Deleting States; Using The Input Buffer; Using The Status Register - Agilent Technologies 3458A User Manual

Deleting States

Using the Input Buffer

Using the Status Register

OUTPUT 722;"RSTATE ACST1"
From the front panel, you can view all stored state names by accessing the
RSTATE command and pressing the up or down arrow key. Once you have
found the correct state, press Enter to recall the state.
You can delete a single stored state using the PURGE command. For
example, to purge the state ACST1, send:
OUTPUT 722;"PURGE ACST1"
You can also use the SCRATCH command to delete all stored states and all
subprograms from memory.
In the multimeter's power-on/PRESET NORM state, the input buffer is
disabled. The means the multimeter must process each GPIB command
individually and wait until the command is executed before releasing the
GPIB bus or accepting another command. In most cases, the controller must
wait until the bus is released before it can continue, which ensures
synchronization between the controller and the instrument. This is most
noticeable on commands that take a long time to execute. For example, if
you run the complete self-test from remote (TEST command), the multimeter
does not release the GPIB bus until the self test is complete, approximately
50 seconds.
With the input buffer enabled, the multimeter temporarily stores commands
in the buffer and immediately releases the GPIB bus. The multimeter then
retrieves and executes the commands in the order received, one by one, from
the input buffer. This allows the controller to perform other operations while
the multimeter is executing commands. The following program enables the
input buffer prior to executing the TEST command.
10 OUTPUT 722;"INBUF ON"
20 OUTPUT 722; "TEST"
30 END
The input buffer holds a maximum of 255 characters. If you send more
characters than the input buffer can hold, the multimeter holds the bus until
buffer space becomes available. When space is available, the remaining
characters are accepted into the input buffer and the bus is released.
When using the input buffer, it may be necessary to know when all buffered
commands have been executed. The multimeter provides this information by
setting bit 4 (ready for instructions) in the status register (discussed next). If
the status register is properly enabled, it drives the GPIB's SRQ (service
request) line true. Your controller will acknowledge this if previously
programmed to accept SRQ as an interrupt.
The status register monitors the following multimeter status information:
Chapter 3 Configuring for Measurements 75