Syntax Overview; Language Dictionary; Command Structure - Ametek Amrel PLA Series Operation Manual

SYNTAX OVERVIEW

Use of the Colon (:)
A co lon is used to separate command mnemonics. It indicates a move down in branch level of the command tree.
The command follows a colon is a sub command of the command immediate before the colon. When colon
precedes the first command mnemonic of a message unit, it becomes root specifier. Its action places the parser
(decoder) at the root of the command tree. Parser can only travel downward the command tree. If another
command at different branch needs to be executed, a root specifier (colon) is required to place parser at origin and
a complete path from root level should also be defined.
Use of the Semicolon (;)
A semico lon is used to separate two command statements with the same command message string. The semicolon
does not change location of the parser in the command tree. On ly command statements that are in the current path
of the first command statement can be combined to form a command message.
Use of the Space ( )
A white space is used to separate a parameter (data) from a command mnemonic. When a command statement
includes parameter, data always follows the last keyword of a command.
Use of the Comma (,)
A comma is used to separate adjacent parameters if a command requires more than one parameter.
Use of the Query (?)
A query command is used to instruct the instrument to send a response message. Queries return either measured
values or internal instrument setting. When a keyword is follo wed by a question mark, it becomes a query. The ?
follows the last keyword of a command statement. You should read back the result of first query before you send
out another query or command. Otherwise, returned data will be lost.
Common Commands:
Commands starting with a * and three-letter mnemonic are called common commands. They are generally not
related to specific device operation but to perform the identical function for all instruments that are compliant with
the IEEE-488.2 interface standard. Common commands can be mixed in with regular Electronic Load commands.
The common command will be executed without affecting the position of the parser.
Root-Level Commands:
The root-level commands are those commands specific to the Electronic Load. They are device specific and can be
mixed with common commands.

LANGUAGE DICTIONARY

The syntax and parameters for the IEEE 488.2 common commands and SCPI commands used by the Electronic Load is
presented in this section. The section starts with description for common commands and then follows by SC PI commands
specific to the electronic load.

COMMAND STRUCTURE

The electronic load has two command types for GPIB and RS-232 interface.
Programming commands
Query commands
System commands
Programming commands send programming instructions or values to the electronic load to control the CV/CC/CR/CP
functions. There are two types of commands, the SCPI command and instruction commands that co -exist in the program.
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