74 Chapter 2
Programming Fundamentals
SCPI Language Basics
keyword The keywords that are allowed for a particular
command are defined in the command syntax
description.
Units Numeric variables may include units. The valid units
for a command depend on the variable type being used.
See the following variable descriptions. The indicated
default units will be used if no units are sent. Units can
follow the numerical value with, or without, a space.
Variable A variable can be entered in exponential format as well
as standard numeric format. The appropriate range of
the variable and its optional units are defined in the
command description.
The following keywords may also be used in commands,
but not all commands allow keyword variables.
• DEFault - resets the parameter to its default value.
• UP - increments the parameter.
• DOWN - decrements the parameter.
• MINimum - sets the parameter to the smallest
possible value.
• MAXimum - sets the parameter to the largest
possible value.
The numeric value for the function’s MINimum,
MAXimum, or DEFault can be queried by adding the
keyword to the command in its query form. The
keyword must be entered following the question mark.
Example query: SENSE:FREQ:CENTER? MAX
Variable Parameters
<integer> is an integer value with no units.
<real> Is a floating point number with no units.
<freq>
<bandwidth> Is a positive rational number followed by optional units.
The default unit is Hertz. Acceptable units include: Hz,
kHz, MHz, GHz.
<time>
<seconds> Is a rational number followed by optional units. The
default units are seconds. Acceptable units include: ks,
s, ms, μs, ns.
<voltage> Is a rational number followed by optional units. The
default units are Volts. Acceptable units include: V, mV,
μV, n V