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Chapter 4  Remote Interface Reference
An Introduction to the SCPI Language
4
An Introduction to the SCPI Language 
SCPI (Standard Commands for Programmable Instruments) is an 
ASCII-based instrument command language designed for test and 
measurement instruments. Refer to “Simplified Programming Overview” 
starting on page 160, for an introduction to the basic techniques used to 
program the function generator over the remote interface. 
SCPI commands are based on a hierarchical structure, also known as a 
tree system. In this system, associated commands are grouped together 
under a common node or root, thus forming subsystems. A portion of the 
SOURce subsystem is shown below to illustrate the tree system. 
SOURce: 
FREQuency 
:STARt {<
frequency>|MINimum|MAXimum} 
:STARt? [MINimum|MAXimum] 
FREQuency 
:STOP {<
frequency>|MINimum|MAXimum} 
:STOP? [MINimum|MAXimum] 
SWEep 
:SPACing {LINear|LOGarithmic} 
:SPACing? 
SWEep 
:TIME {<
seconds>|MINimum|MAXimum} 
:TIME? [MINimum|MAXimum] 
SWEep 
:STATe {OFF|ON} 
:STATe? 
SOURce is the root keyword of the command, FREQuency and SWEep are 
second-level keywords, and STARt and STOP are third-level keywords. 
A colon ( : ) separates a command keyword from a lower-level keyword. 
33210A users guide.book Page 265 Wednesday, July 16, 2008  11:16 AM