More About Oscilloscope Commands
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Keysight InfiniiVision M9241/42/43A PXIe Oscilloscopes SCPI Programmer's Guide
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Valid Command/Query Strings
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"Tree Traversal Rules and Multiple Commands"
Program Message Syntax
To program the instrument remotely, you must understand the command format
and structure expected by the instrument. The IEEE 488.2 syntax rules govern how
individual elements such as headers, separators, program data, and terminators
may be grouped together to form complete instructions. Syntax definitions are
also given to show how query responses are formatted. The following figure shows
the main syntactical parts of a typical program statement.
Instructions (both commands and queries) normally appear as a string embedded
in a statement of your host language, such as Visual Basic or C/C++. The only time
a parameter is not meant to be expressed as a string is when the instruction's
syntax definition specifies <block data>, such as <learn string>. There are only a
few instructions that use block data.
Program messages can have long or short form commands (and data in some
cases — see
"Long Form to Short Form Truncation Rules"
on page 1370), and
upper and/or lower case ASCII characters may be used. (Query responses,
however, are always returned in upper case.)
Instructions are composed of two main parts:
• The header, which specifies the command or query to be sent.
• The program data, which provide additional information needed to clarify the
meaning of the instruction.
Instruction Header
The instruction header is one or more mnemonics separated by colons (:) that
represent the operation to be performed by the instrument.
":DISPlay:LABel ON" is a command. Queries are indicated by adding a question
mark (?) to the end of the header, for example, ":DISPlay:LABel?". Many
instructions can be used as either commands or queries, depending on whether or
":DISPLAY:LABEL ON"
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