BNC 645 - Manual (Page 120)

120
B
Remote Interface Reference
B.1 An Introduction to the SCPI Language
SCPI (Standard Commands for Programmable Instruments) is an
ASCII-based instrument command language designed for testing and
measurement instruments. It is 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
explain 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]
SOURce is the root keyword of the command, SWEep and FREQuency are
second-level keywords, and STARt and STOP are third-level keywords. A
colon ( : ) separates a command keyword from a lower-level keyword.
B.1.1 Command Format Used in This Manual
The command format used in this manual is shown below:
STARt {<frequency>|MINimum|MAXimum}