VI-700 V&l Source
17
Appendix A
SCPI COMMAND REFERENCE
SCPI is an acronym for “Standard Commands for
Programmable Instruments”. For additional informa-
tion 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 define a set of common commands for use on
the IEEE 488 bus. IEEE 488.2 devices are supposed
to receive messages in a more flexible 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: RE-
SPONSE MESSAGE. As part of the protocol stan-
dardization the following rules were generated:
(;)
Semicolons separate messages.
(:)
Colons separate command words.
(,)
Commas separate data fields.
<nl>
Line feed and/or EOI as last character
terminates a 'program message'.
Line feed (ASCII 10) and EOI
terminates a RESPONSE MESSAGE.
(*)
Asterisk defines a 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 instrument 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 capitals denotes
the abbreviated form of the keyword. Either the ab-
breviated or whole keyword may be used when en-
tering a complete command. There must be a space
between the command and a parameter or channel
list. Multiple SCPI commands may be concatenated
together as a compound command by using semico-
lons as command separators.
Keywords shown inside braces [ ] are defaults, and
are optional when constructing a PROGRAM MES-
SAGE.
Commands not recognized have no effect on the unit's
operation and will set the corresponding bits in the
Standard Event Status Register. SCPI commands that
end with a question mark '?' are queries. All queries
should be followed by reading their response to avoid
data loss.
SCPI COMMAND REF
