Rohde & Schwarz R&S FPH, User Manual

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Remote Commands
R&S ® Spectrum Rider FPH
274 User Manual 1321.1011.02 ─ 06.00
"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 (Standard Commands for Programmable Instruments) describes a standard
command set for programming instruments, irrespective of the type of instrument or
manufacturer. The goal of the SCPI consortium is to standardize 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 systems 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 282).
Remote command examples
Not all commands used in the following examples are implemented in the instrument.
● Structure of a Command .......................................................................................274
● Parameters ............................................................................................................279
● Structure of a Program Message .......................................................................... 281
● Responses to Queries ...........................................................................................282
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 ............................................................................................ 274
● Device-Specific Commands ..................................................................................275
● Overview of Syntax Elements ............................................................................... 278
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