Error Output - HP 8753E Programming And Command Reference Manual

If a bit in one of the event-status registers is enabled, and therefore, the
summary bit in the status byte is enabled, an SRQ will be generated.
The SRQ will not be cleared until one of the five following conditions
transpire:
1. The event-status register is read, clearing the latched bit.
2. The summary bit in the status byte is disabled.
3. The event-status register bit is disabled.
4. The status registers are cleared with the
5. An instrument preset is performed.
Service requests generated when there are error messages or when the
instrument is waiting for the Group Execute Trigger (GET) command are
cleared by:
reading the errors
n
issuing GET (disabling the bits)
n
clearing the status registers
n

Error Output

When an error condition is detected in the analyzer, a message is
generated, displayed on the analyzer's display screen, and placed in the
error queue. Error messages consist of an error number followed by an
ASCII string no more than 50-characters long. The string contains the
same message that appears on the analyzer's display. The error queue
holds up to 20 error messages in the order in which they occur. The
error messages remain in the error queue until the errors are read by
the system controller using the command OUTPERRO. The OUTPERRO
command outputs one error message.
Note
The error queue can only be cleared by performing an
instrument preset or by cycling the line power. In
order to keep the queue up-to-date, it is important to
read all of the messages out of the queue each time
errors are detected.
HP-IB Programmi ng and Command Reference Guide