Chapter 8
SCPI
Syntax and notation
4460 GSM System Option and 4468 EDGE System Option
Version 12.20
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Parameters
Many commands require parameters to be specified. Those parameters are
placed behind the command, separated by at least one blank (space).
The following types of parameters do exist on the 4400:
–
Numeric parameters
. These are integers, floating point numbers (with a
maximum of 6 decimals) or exponential numbers (see specifications IEEE
488.2 NRf format or ANSI X3.42-1975 for details).
Some numeric parameters may carry a physical unit (details can be found in
subsection variables of the RAPID! chapter).
Example:
:RFG:FREQ 930.071965 MHz
makes the RF generator switch
to the specified transmission frequency.
–
Boolean parameters
are specified using the binary numbers 0 | 1, or ON |
OFF instead.
–
Enumerated parameters
are strings that only may be selected from a
predefined list. To distinguish them from string parameters, the enumerated
parameters
must not
be put in quotation marks.
Example:
:CONFigure:GSM:TYPE GSM9001800
sets the 4400 to work
as test set for GSM 900/1800.
–
String parameters
are user-defined strings.
Example:
PROGram:NAME “/rapid/examples/ms_test.rbm”
loads
the specified RAPID! program file.
–
Block parameters
are a special case and will be described with the related
commands.
Queries
Many commands also have a query form. These queries enable you to read out
the current value of parameters or the results of measurements.
For a query, simply add a question mark to the command (without any spaces or
other symbols in-between).
Example:
:RFG:FREQ?
returns the current transmission frequency of the RF
generator.
Common commands
Common commands are defined in IEEE 488.2.
They work on the device itself (and on any subsystem) and always start with an
asterisk (*).
Example:
*RST
resets the 4400 and sets all system parameters to default
values.
NOTE
The decimal point of floating point numbers
must be
the dot (.) within SCPI as
a comma (,) will always be interpreted as the separator between two parame-
ters (see Notes below for details).
NOTE
The result of a query is saved internally on the 4400. Details can be found in
subsection