R&S 1129.7246.03, Operating Manual

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R&S ESU Remote Control – Basics
Status Reporting System
5.32 Operating Manual 1302.6163.12 - 03
The instrument first has to be set for the parallel poll using quick-BASIC command
"IBPPC()". This command allocates a data line to the instrument and determines
whether the response is to be inverted. The parallel poll itself is executed using
"IBRPP()".
The parallel-poll method is mainly used in order to quickly find out after an SRQ
which instrument has sent the service request if there are many instruments con-
nected to the GPIB. To this effect, SRE and PPE must be set to the same value. A
detailed example as to the parallel poll is to be found in chapter
“Remote Control –
Programming Examples” .
5.7.4.4 Query by Means of Commands
Each part of every status register can be read by means of queries. The individual
commands are indicated in the detailed description of the registers. What is returned
is always a number which represents the bit pattern of the register queried. Evaluat-
ing this number is effected by the controller program.
Queries are usually used after an SRQ in order to obtain more detailed information
on the cause of the SRQ.
5.7.4.5 Error Queue Query
Each error state in the instrument leads to an entry in the error queue. The entries of
the error queue are detailed plain-text error messages which can be looked at in the
ERROR menu via manual operation or queried via the GPIB using
SYSTem:
ERRor?
command. Each call of
SYSTem:ERRor?
provides an entry from the error
queue. If no error messages are stored there any more, the instrument responds
with 0, "No error".
The error queue should be queried after every SRQ in the controller program as the
entries describe the cause of an error more precisely than the status registers.
Especially in the test phase of a controller program the error queue should be que-
ried regularly since faulty commands from the controller to the instrument are
recorded there as well.