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PRS-300 Series
APPENDIX A 33
Appendix A
SCPI COMMAND REFERENCE
SCPI is an acronym for “Standard Com-
mands for Programmable Instruments”. For
additional information or an on-line copy of
this standard, see:
http://www.scpiconsortium.org.
The IEEE 488.2 Standard was established
in 1987 to standardize message protocols and
status reporting and to de
fi ne a set of common
commands for use on the IEEE 488 bus. IEEE
488.2 devices are supposed to receive mes-
sages in a more
fl exible manner than they send.
A message sent from GPIB controller to GPIB
device is called: PROGRAM MESSAGE.
A message sent from device to controller is
called: RESPONSE MESSAGE. As part of the
protocol standardization the following rules
were generated:
(;) Semicolons separate messages.
(:) Colons separate command
words.
(,) Commas separate data fi elds.
<nl> Line feed and/or EOI as last
character
terminates a ‘program message’.
Line feed (ASCII 10) and EOI
terminates a RESPONSE MESSAGE.
(*)
Asterisk de fi nes a IEEE 488.2
common command.
(?) Ends a query where a reply is
expected.
SCPI builds on the programming syntax
of IEEE-488.2 to give the programmer the
capability of handling a wide variety of instru-
ment functions in a common manner. This
gives all instruments a common “look and
feel”. SCPI commands are not case-sensitive.
The portion of commands shown in capi-
tals denotes the abbreviated form of the key-
word. Either the abbreviated or whole keyword
may be used when entering a complete com-
mand. There must be a space between the com-
mand and a parameter or channel list. Multiple
SCPI commands may be concatenated together
as a compound command by using semicolons
as command separators.