Ametek EC1000S, Руководство пользователя

Страница: 205 / 291

User Manual EC1000S
California Instruments 201
Figure 6-2. Partial Command Tree

Root level
The command tree top level is the root. With SCPI, the current path is set to the root, as
shown below.
○ Immediately after the device power source goes on
○ When the device receives a “root specifier”
The root specifier is a colon that is attached to the start of a command string to indicate that
the current path is set to the root.
○ When the device has received a “message terminator”
The message terminator is a line feed (LF) at the end of an SCPI message. The current
path is returned to the root level when the device receives a message terminator.

Current path
The current path is a command level within the command tree, which specifies the command
level that will be searched first when the user sends a command.
2) Path separator
The path separator (:) separates the current keyword from the keyword at the next lower level.
Each time a colon (:) is detected in a command string, the current path is moved one level
downward.
When a colon appears at the start of a command string, it indicates that the current path is set to the
root. This starting colon also can be freely omitted.
When a semicolon (;) is used to separate a command string, subsystem command on the same
level can be accessed without changing the current path.
:SOUR:FREQ 1000
FREQuency command, belongs to SOURce subsystem
SOURce subsystem command (SOURce is root command)
Sets current path to root