Ceyear 1465 Series, Programming Manual

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2 Remote Control
2.1 Remote control basis
10
For example: LIST:POWer 5
Table 2.3 Command Syntax
Character, Keyword and Syntax Example
Upper-case characters represent the minimum character set
required by
command execution. [:SOURce]:FREQuency[:CW]?,
FREQ is the short-format part of the
command.
The lower-case characters portion of command is optional;
Such flexible
format is called ―flexible listening‖. For more information,
please refer to ―Command
Parameter and Response‖.
:FREQuency
:FREQ, :FREQuency or
:FREQUENCY,
any of which is correct.
When a colon is placed between two command mnemonics,
it moves
the current path down one level in the command tree. For
more information, please refer to the command
path part of ―Command Trees‖.
:TRIGger[:SEQuence]:SOURce?
TRIGger is the topmost keyword of this
command.
If a command requires more than one parameter, you must
separate adjacent parameters
using a comma. Parameters do not affect path layers
as they are not the portion of the command path.
[:SOURce]:LIST:DWELl <val>{,<val>}
A semicolon separates 2 adjacent commands without
affecting the current
path.
:FREQ 2.5GHZ; :POW 10DBM
White space characters, such as <space> or <tab>, are
generally ignored
so long as they don‘t appear between or among
. However, the command and parameter must be separated
by a blank character, without affecting the current path. :FREQ uency or :POWer :LEVel6.2 is not
allowed.
:LEVel and 6.2 must be separated by a
space.
i.e. :POWer:LEVel 6.2
4) Command tree
Most remote control programming tasks involve instrument-specific commands. When such a command
is parsed, the SCPI will use a structure similar to the file structure, and it is called as a command tree, as
shown in Figure 2.2:
Figure 2.2 Simplified Command Tree Diagram
The top command is root command, or simply ―root‖. In the case of command parsing, the command at
the next layer is reached by following a specific route based on the tree structure. For
example: :POWer:ALC:SOURce
？
where, POWer stands for AA,: ALC stands for BB, :SOURce stands
for GG, and the whole command path is (:AA:BB:GG).
A software module in the instrument software
—the command interpreter—is responsible for parsing
AA
BB
CC
DD
EE
FF
GG HH
JJ
Root