Rohde & Schwarz 1321.0615.02, User Manual

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Remote Commands
R&S
®
Spectrum Rider FPH
300 User Manual 1321.1011.02 ─ 11
"Query UNTERMINATED" to the status reporting system. No data are sent to the con-
troller, the controller waits until it has reached its time limit. This behavior is defined by
IEEE 488.2 and SCPI.
13.4 SCPI Command Structure and Syntax
SCPI describes a standard command set for programming instruments, irrespective of
the type of instrument or manufacturer. The goal of the SCPI consortium is to standard-
ize the device-specific commands to a large extent. For this purpose, a model was
developed which defines the same functions inside a device or for different devices.
Command systems were generated which are assigned to these functions. Thus it is
possible to address the same functions with identical commands. The command sys-
tems are of a hierarchical structure.
SCPI is based on standard IEEE 488.2, i.e. it uses the same syntactic basic elements
as well as the common commands defined in this standard. Part of the syntax of the
device responses is defined with greater restrictions than in standard IEEE 488.2 (see
Chapter 13.4.4, "Responses to Queries" , on page 308).
Remote command examples
Not all commands used in the following examples are implemented in the instrument.
● Structure of a Command .......................................................................................300
● Parameters ............................................................................................................305
● Structure of a Program Message .......................................................................... 307
● Responses to Queries ...........................................................................................308
13.4.1 Structure of a Command
The commands consist of a so-called header and, in most cases, one or more parame-
ters. Header and parameter are separated by a "white space" (ASCII code 0 to 9, 11 to
32 decimal, e.g. blank). The headers may consist of several key words. Queries are
formed by directly appending a question mark to the header.
● Common Commands ............................................................................................ 300
● Device-Specific Commands ..................................................................................301
● Overview of Syntax Elements ............................................................................... 304
13.4.1.1 Common Commands
Common commands consist of a header preceded by an asterisk "*" and one or sev-
eral parameters, if any.
SCPI Command Structure and Syntax
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