California Instruments 2001RP, User And Programming Manual

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User and Programming Manual - Rev N
Query Indicator
Following a header with a question mark turns it into a query (VOLTage?, VRANGe?).
Message Unit Separator
When two or more message units are combined into a compound message, separate the units
with a semicolon (VOLT 100;FREQ 60).
Root Specifier
When it precedes the first header of a message unit, the colon becomes the root specifier. It
tells the command parser that this is the root or the top node of the command tree. Note the
difference between root specifiers and header separators in the following examples:
SOURce:VOLTage:LEVel 100 All colons are header separators
:SOURce:VOLTage:LEVel 100 Only the first colon is a root specifier
SOURce:VOLTage:LEVel 100;:FREQuency 55 Only the third colon is a root specifier
You do not have to precede root-level commands with a colon; there is an implied colon in front
of every root-level command.
Message Terminator
A terminator informs SCPI that it has reached the end of a message. The only permitted
message terminator is:
•
newline (<NL>), which is ASCII decimal 10 or hex 0A.
In the examples of this manual, there is an assumed message terminator at the end of each
message. If the terminator needs to be shown, it is indicated as <NL> regardless of the actual
terminator character.
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