Specifications

30 Chapter 2
Outline of Remote Control
Outline of GPIB remote control system
The concept of command tree
The command at the highest-level position in the command tree hierarchy is called “root
command” or simply “root.” To access a lower command in the tree structure’s hierarchy, a
particular “path” has to be specified in the same way as a directory path in the DOS file
system. The current path is set as “root” after the power is turned on or a reset is executed.
Depending on the special symbols in the massage, the setting of the path changes as
follows.
Message terminator
A message terminator such as <new line> sets the current path as the
“root.”
Colon (:) When a colon is located between two command mnemonics, the colon
lowers the level of the current path on the command tree. When it is
used as the first character of a command, it specifies the command
mnemonic to follow it as the command of root level.
Semi-colon (;) A semi-colon divides two commands within one message without
changing the current path.
Figure 2-2 shows an example of using the colon and semi-colon for efficient access of
various commands within the command tree.
Figure 2-2 Usage of colon and semi-colon