174
Programming the Test Set
IEEE Common GPIB Commands
Query Instrument Options Returns a string of all the installed instrument options. It is a comma separated list with quotes, such as:
“503,P03,PFR”.
To be IEEE compliant, this command should return an arbitrary ascii variable that would not begin and
end with quotes. But the quotes are needed to be backward compatible with previous SA products and
software. So, the actual implementation will use arbitrary ascii. But quotes will be sent as the first and
last ascii characters that are sent with the comma-separated option list.
Recall Instrument State This command recalls the instrument state from the specified instrument memory register.
If the state being loaded has a newer firmware revision than the revision of the instrument, no state is
recalled and an error is reported
If the state being loaded has an equal firmware revision than the revision of the instrument, the state will
be loaded.
Backwards Compatibility Notes: The ESA/PSA/VSA products do not meet all the requirements for the *OPC
command specified by IEEE 488.2. This is corrected for X-Series. This will
sometimes cause behavior that is not backward compatible, but it will work as
customers expect.
Commands such as, *OPC/*OPC?/*WAI/*RST used to be global. They
considered front panel operation in conjunction with the GPIB functionality.
Now they are evaluated on a per channel basis. That is, the various rear panel
remote ports and the front panel i/o are all considered separately. Only the
functionality initiated on the port where the *OPC was sent, is considered for
its operation.
*OPC used to hold off until the operation bits were cleared. Now it holds off
until all overlapping commands are completed. Also, earlier instruments did
not wait for completion of all processes, only the ones identified here (in the
STATus:OPERation register):
Calibrating: monitored by PSA, ESA, VSA (E4406A)
Sweeping: monitored by PSA, ESA, VSA (E4406A)
Waiting for Trigger: monitored by PSA, ESA, VSA (E4406A)
Measuring: monitored by PSA and ESA (but not in all Modes).
Paused: monitored by VSA (E4406A).
Printing: monitored by VSA (E4406A).
Mass memory busy: monitored by VSA (E4406A).
Initial S/W Revision: Prior to A.02.00
Remote Command: *OPT?
Initial S/W Revision: Prior to A.02.00