Agilent Technologies 4294A, Programming Manual

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Chapter 2 29
Remote Control, Overview
Sending GPIB Command Messages
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Sending GPIB Command Messages
GPIB commands
GPIB commands can be grouped into two classes:
IEEE common commands
Commands defined by IEEE488.2
Agilent 4294A commands
Commands specific to the Agilent 4294A. These include all of the measurement functions
and some of the general-purpose functions.
Message syntax
Descriptions of the syntax used in sending program messages from the GPIB are given
below. A program message is sent from an external controller to a measuring instrument.
The content of a program message is composed of a series of commands that are properly
set off and terminated by delimiters and a message terminator.
Uppercase letters and lowercase letters
The difference between uppercase and lowercase letters is disregarded.
Program message terminator
A program message must terminate with one of three program message terminators: <new
line>, <^END>, or <new line><^END>. <^END> means that EOI turns to the active level
on the GPIB interface as soon as the immediately preceding data byte is sent out. For
example, the OUTPUT statement of HP BASIC automatically sends a message terminator
along with the last data byte.
Parameters
A space (ASCII code 32) must be put between the last command mnemonic and the first
parameter.
To send two or more parameters by a single command, each parameter must be delimited
by a comma (,).
A message including two or more commands
To send two or more commands within a single message, each command must be delimited
by a semicolon (;). An example is given below in which the “PRES” command and the
“*CLS” command are sent within a single message.
OUTPUT 717;"PRES;*CLS"