Agilent Technologies E5052A, Руководство программиста

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Overview of Remote Control
Sending SCPI command messages
Sending SCPI command messages
Types and structure of commands
The SCPI commands available for the E5052A are classified into two groups as follows.
E5052A commands
E5052A Commands specific to the E5052A. These cover all measurement functions of the
E5052A as well as some general-purpose functions. The commands in this group are
arranged in a hierarchical structure called the command tree. Each command consists of
character strings (mnemonics) indicating the hierarchical levels and colon (:) separators
between these levels.
IEEE common commands
Commands used to cover general-purpose functions defined in IEEE488.2 available to all
instruments that support this standard. The commands in this group have an asterisk (*) at
the beginning. These commands have no hierarchical structure.
Concepts of the command tree
The command at the top of the command tree is called “root command” or simply “root.”
To access lower level commands in the tree, you need to specify a specific path, like a
directory path in the DOS file system. After power-on or reset, the current path is set as the
root. Special characters in messages change the path setting as described below.
Message terminator A message terminator such as the
<new line> character sets the current path as the root.
Colon (:) A colon between two command mnemonics lowers the level of the
current path in the command tree. A colon used as the first character of
a command specifies the command mnemonic that follows as the
root-level command.
Semicolon (;) A semicolon does not change the current path but separates two
commands in the same message.
Figure 2-10 shows an example of how to use colons and semicolons to efficiently access
commands in the command tree.