KEPCO BOP 1KW-MG Operator Manual, Firmware Ver.4.12 and higher - Manual (Page 128)

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BOP HIPWR 031014
3.6.4.6 MESSAGE UNIT SEPARATOR
When two or more message units are combined in a program message, they must be separated
by a semicolon (;) (e.g., VOLT 15;MEAS:VOLT? and CURR 12; CURR:TRIG 12.5).
3.6.4.7 ROOT SPECIFIER
The root specifier is a colon (:) that precedes the first keyword of a program message. This
places the parser at the root (top left, Figure 3-18) of the command tree. Note the difference
between using the colon as a keyword separator and a root specifier in the following examples:
VOLT:LEV:IMM 16 Both colons are keyword separators.
:CURR:LEV:IMM 4 The first colon is the root specifier, the other two are keyword separators.
VOLT:LEV 6;:CURR:LEV 15 The second colon is the root specifier, the first and third are key-
word separators
:INIT ON;:TRIG;:MEAS:CURR?;VOLT? The first three colons are root specifiers.
3.6.4.8 MESSAGE TERMINATOR
The message terminator defines the end of a message. One message terminator is permitted:
• new line (<NL>), ASCII 10 (decimal) or 0A (hex)
NOTE: Kepco power supplies require a message terminator at the end of each program mes-
sage. The examples shown in this manual assume a message terminator will be added
at the end of each message. Where a message terminator is shown it is represented
as <NL> regardless of the actual terminator character.
3.6.5 UNDERSTANDING THE COMMAND STRUCTURE
Understanding the command structure requires an understanding of the subsystem command
tree illustrated in Figure 3-18. The “root” is located at the top left corner of the diagram. The
parser goes to the root if:
• a message terminator is recognized by the parser
• a root specifier is recognized by the parser
Optional keywords are enclosed in brackets [ ] for identification; optional keywords can be omit-
ted and the power supply will respond as if they were included in the message. The root level
keyword [SOURce] is an optional keyword. Starting at the root, there are various branches or
paths corresponding to the subsystems. The root keywords for the BOP Power Supply are
:ABORt, :CALibrate, :DISPlay, :INITiate, :LIST, :MEASure, :OUTPut, [:SOURce], :STATus,
:SYSTem and :TRIGger. Because the [SOURce] keyword is optional, the parser moves the path
to the next level, so that VOLTage, CURRent, and FUNCtion commands are at the root level.
Each time the parser encounters a keyword separator, the parser moves to the next indented
level of the tree diagram. As an example, the STATus branch is a root level branch that has
three sub-branches: OPERation, PRESet, and QUEStionable. The following illustrates how
SCPI code is interpreted by the parser: