Rohde & Schwarz SML01, Operating Manual

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R&S®SML / R&S®SMV03 Structure and Syntax of Device Messages
1090.3123.12 E-6 5.7
SOURce
POWer AM FM
MODE INTernal EXTernal STATe POLarity
POLarity COUPling
Fig. 5-1 Tree structure of SCPI command systems using the SOURce system as an example
Some key words occur at several levels within one command system.
Their effect depends on the structure of the command, that is to say, at
what position of the header of a command they are inserted.
Example:
:SOURce:FM:POLarity NORMal
This command contains the key word POLarity at the third
command level. It defines the polarity between the modulator
and the modulation signal.
Example
:SOURce:FM:EXTernal:POLarity NORMal
This command contains the key word POLarity at the fourth
command level. It defines the polarity between the modulation
voltage and the resulting direction of the modulation only for the
external signal source indicated.
Optional key words: Some command systems permit certain key words to be optionally inserted
into the header or omitted. These key words are marked in the description
by square brackets. The instrument must recognize the full command
length for reasons of compatibility with the SCPI standard. Some
commands can be considerably shortened by omitting optional key words.
Example:
[SOURce]:POWer[:LEVel][:IMMediate]:OFFSet 1
This command immediately sets the offset of the signal to 1 dB.
The following command has the same effect:
POWer:OFFSet 1
Note: An optional key word must not be omitted if its effect is specified
in greater detail by means of a numerical suffix.
Long and short form:
Key words have a long form and a short form. Either the long form or the
short form may be entered, other abbreviations are not permissible.
Example:
STATus:QUEStionable:ENABle 1= STAT:QUES:ENAB 1
Note: The short form is characterized by upper-case letters, the long
form corresponds to the complete word. Upper-case and lower-
case notation only serve the above purpose, the device itself
does not make any difference between upper-case and lower-
case letters.