Introduction to scpi – Teledyne LeCroy PXA125 User Manual

Page 140

User Manual PXA125

Programming Reference 4-22

Introduction To
SCPI

Commands to program the instrument over the GPIB are defined by
the SCPI 1993.0 standard. The SCPI standard defines a common
language protocol. It goes one step further than IEEE-STD-488.2 and
defines a standard set of commands to control every programmable
aspect of the instrument. It also defines the format of command
parameters and the format of values returned by the instrument.

SCPI is an ASCII-based instrument command language designed for
test and measurement instruments. SCPI commands are based on a
hierarchical structure known as a tree system. In this system,
associated commands are grouped together under a common node or
root, thus forming subsystems.

Part of the OUTPut subsystem is shown below to illustrate the tree
system:

OUTPut

:FILTer

[:LPASs]

{NONE|25M|50M|ALL}

[:STATe] OFF | ON

OUTPut is the root keyword of the command; FILTer and STATe are
second level keywords. LPASs is third level keyword. A colon ( : )
separates a command keyword from a lower level keyword.