Annex; Remote Control Basics; Messages - R&S SGT100A User Manual

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R&S SGT100A

15 Annex

15.1 Remote Control Basics

This chapter provides basic information on operating an instrument via remote control.

15.1.1 Messages

The messages transferred on the data lines are divided into the following categories:
●
Interface messages
Interface messages are transmitted to the instrument on the data lines, with the
attention line being active (LOW). They are used to communicate between the con-
troller and the instrument. Interface messages can only be sent by instruments that
have GPIB bus functionality. For details see the sections for the required interface.
●
Instrument messages
Instrument messages are employed in the same way for all interfaces, if not indica-
ted otherwise in the description. Structure and syntax of the instrument messages
are described in
detailed description of all messages available for the instrument is provided in the
chapter "Remote Control Commands".
There are different types of instrument messages, depending on the direction they
are sent:
–
–
Commands
Commands (program messages) are messages the controller sends to the instrument.
They operate the instrument functions and request information. The commands are
subdivided according to two criteria:
●
According to the effect they have on the instrument:
–
–
●
According to their definition in standards:
–
–
User Manual 1176.8674.02 ─ 07
Chapter 15.1.3, "SCPI Command
Commands
Instrument responses
Setting commands cause instrument settings such as a reset of the instru-
ment or setting the frequency.
Queries cause data to be provided for remote control, e.g. for identification of
the instrument or polling a parameter value. Queries are formed by directly
appending a question mark to the command header.
Common commands: their function and syntax are precisely defined in stan-
dard IEEE 488.2. They are employed identically on all instruments (if imple-
mented). They refer to functions such as management of the standardized sta-
tus registers, reset and self-test.
Instrument control commands refer to functions depending on the features of
the instrument such as frequency settings. Many of these commands have also
been standardized by the SCPI committee. These commands are marked as
Remote Control Basics
Structure", on page 526. A
Annex
525