Parameter Types - Keysight Technologies RP7900 Serie Guide D'utilisation Et De Maintenance

5 SCPI Programming Reference
Square brackets ( [ ]) enclose some syntax elements - nodes and parameters for example. This
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indicates that the element is optional and can be omitted. The brackets are not sent with the com-
mand string. In the case of an optional parameter, if you do not specify a value for an optional para-
meter the instrument will ignore the parameter. In the FETCh:CURRent? example above, the
optional <startindex> and <points> parameters let you return array data starting at startindex and
containing the specified number of data points. If these parameters are not specified, the query
returns all of the array data.
Braces ( { } ) indicate parameters that may be repeated zero or more times. It is used especially for
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showing lists. The notation <value>{,<value>} shows that the first value must be entered, while
additional values may be omitted or may be entered one or more times.

Parameter Types

The SCPI language defines several data formats to be used in commands and queries.
Numeric Parameters
Commands that require numeric parameters will accept all commonly used decimal representations
of numbers including optional signs, decimal points, and scientific notation. If a command accepts only
certain specific values, the instrument will automatically round the input numeric parameters to the
accepted values. The following command requires a numeric parameter for the voltage value:
[SOURce:]VOLTage 50V|MIN|MAX
Note that special values for numeric parameters such as MINimum, MAXimum, and INFinity are also
accepted. Instead of selecting a specific value for the voltage parameter, you can substitute MIN to
set the voltage to its minimum allowable value, MAX to set it to its maximum allowable value.
You can also send engineering unit suffixes with numeric parameters (e.g., V for volts, A for amperes,
W for Watts). All parameters values are in base units.
Discrete Parameters
Discrete parameters are used to program settings that have a limited number of values (like
IMMediate, EXTernal, or BUS). They may have a short form and a long form just like command
keywords. You can use upper- or lower-case letters. Query responses will always return the short
form in all upper-case letters. The following command requires a discrete parameter for the display
settings:
DISPlay:VIEW METER_VI|METER_VP|METER VIP
Boolean Parameters
Boolean parameters represent a single binary condition that is either true or false. For a false
condition, the instrument will accept "OFF" or "0". For a true condition, the instrument will accept "ON"
or "1". When you query a Boolean setting, the instrument will always return "0" or "1". The following
command requires a Boolean parameter:
DISPlay OFF|0|ON|1
184 Keysight RP7900 Series Operating and Service Guide