ICS 8099, Инструкция по эксплуатации

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A1
A1.3 SCPI COMMANDS
A1.3.1 Introduction
SCPI (Standard Commands for Programmable Instruments) builds on the
programming syntax of 488.2 to give the programmer the capability handling
a wide variety of instrument functions in a common manner. This gives all
instruments of the same type a common "look and feel".
SCPI commands use common command words defined in the SCPI specifica-
tion. Control of any instrument capability that is described in SCPI shall be
implemented exactly as specified. Guidelines are included for adding new
defined commands in the future as new instruments are introduced without
causing programming problems.
SCPI is designed to be laid on top of the hardware - independent portion of
the IEEE 488.2 and operates with any language or graphic instrument program
generators. The obvious benefits of SCPI for the ATE programmer is in reduc-
ing the learning time on how to program multiple SCPI instruments since they
all use a common command language and syntax.
A second benefit of SCPI is that its English like structure and words are self
documenting, eliminating the needs for comments explaining cryptic instrument
commands. A third benefit is the reduction in programming effort to replace
one manufacturer's instrument with one from another manufacturer, where both
instruments have the same capabilities.
This consistent programming environment is achieved by the use of defined
program messages, instrument responses and data formats for all SCPI devices,
regardless of the manufacturer.
A1.3.2 Command Structure and Examples
SCPI commands are based on a hierarchical structure that eliminates the need
for most multi-word mnemonics. Each key word in the command steps the
device parser out along the decision branch - similar to a squirrel hopping
from the tree trunk out on the branches to the leaves. Subsequent keywords
are considered to be at the same branch level until a new complete command
is sent to the device. SCPI commands may be abbreviated as shown by the
capital letters in Figure A-2 or the whole key word may be used when entering
a command. Figure A-2 shows some single SCPI commands for setting up
and querying a serial interface.