PACE Series SCPI Manual
K0472 Revision A
2-1
2
COMMAND STRUCTURE
This section describes the structure of the commands and data sent and received by a PACE
Series Controller/Calibrator.
2.1
Notation
All SCPI commands are based on a hierarchical tree structure consisting of key words and
parameters. Associated commands are grouped together under a common node in the
hierachy.
In the command tree the command A is the root command. A tree pointer is used to decode
the SCPI commands. At power-up the pointer goes to the root command.
2.2
Message Terminators
All SCPI commands are terminated by line feed i.e., either <newline> (ASCII character,
decimal 10), EOI for IEEE. After receiving a termination character the tree pointer returns to
the root command.
Colon
A colon moves the current path down one level in the command tree, (e.g., the colon in
SOURCE:PRESSURE specifies PRESSURE the is one level below SOURCE). When the colon is
the first character of the command, it specifies that the next command is a root level
command (e.g., :SOURCE specifies that SOURCE is a root level command).
Semicolon
A semicolon separates two commands in the same message without changing the tree
pointer.
(e.g., with reference to the tree):A:B:E;F;G
This equivalent to sending three messages:
:A:B:E
:A:B:F
:A:B:G
root
Level 1
Level 2
A
B
C
D
E
F
G
H
J
