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11.2
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Protocol SCPI
11.2.1 Physical layer
SCPI is based over the LAN interface that can be connected via a commercial RJ-45 cable to a network with
TCP/IP protocol. The TCP port used is 23 (Telnet port) or 5025 (both are enabled on the device).
11.2.2 Command syntax
SCPI commands to an instrument may either perform :
• Command operation (e.g. switching a power supply on)
• Query operation (e.g. reading a voltage). Queries are issued to an instrument by appending a question-mark
to the end of a command.
Use a semicolon ( ; ) to separate multiple commands e.g. *IDN ? ; VALID ?
Abbreviating commands
The command syntax shows some characters in a mixture of upper and lower case. Abbreviating the command
to only sending the upper case has the same meaning as sending the upper and lower case command.
For example, the command "DATe" could also alternatively be abbreviated "DAT"
Arguments
Some commands require an additional argument. Arguments are given after the command, and are separated
by a space.For example, the command to set the trigger mode of an instrument to "normal" may be given as
"TRIGger :MODe NORMal". Here, the word "NORMal" is used as the argument to the "TRIGger :MODe" command.
There are several types of data items :
• Alphanumerical data : 1 to 12-character words that can be alphabetical (upper or lower case) digital or the "-"
character (95d). A word always starts with an alphabetical character. For example, for a non-digital parameter :
S1M.
• Decimal digital data : Made of a significand and, possibly, an exponent, and displayed as a chain of ASCII-
coded characters starting with a digit or a sign (+ or -).
• Text : Any chain of characters under 7-bit ASCII code, between quotation marks (") or apostrophes ('). For
example : "Channel 1"
DAS
Manuel utilisateur
CHAPITRE 11. ANNEXES
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