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3 query indicator, 4 data, 5 data separator – KEPCO BOP 1KW-MG Operator Manual, Firmware Ver.2.01 to 2.37 User Manual

Page 118: Figure 3-19. message structure, 6 message unit separator, 7 root specifier, Query indicator -58, Data -58, Data separator -58, Message unit separator -58

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BOP HIPWR 022108

3.6.4.3

QUERY INDICATOR

The question mark (?) following a keyword is a query indicator. This changes the command into
a query. If there is more than one keyword in the command, the query indicator follows the last
keyword. (e.g., VOLT? and MEAS:CURR?).

3.6.4.4

DATA

Some commands require data to accompany the keyword either in the form of a numeric value
or character string. Data always follows the last keyword of a command or query (e.g.,
VOLT:LEV:TRIG 14 or SOUR:VOLT? MAX

3.6.4.5

DATA SEPARATOR

Data must be separated from the last keyword by a space (e.g., VOLT:LEV:TRIG 14 or
SOUR:VOLT? MAX

FIGURE 3-19. MESSAGE STRUCTURE

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 3.5;:OUTP ON;:CURR?

MESSAGE TERMINATOR

KEYWORD

QUERY INDICATOR

ROOT SPECIFIER

MESSAGE UNIT SEPARATOR

DATA

KEYWORD

KEYWORD SEPARATOR

KEYWORD

MESSAGE UNIT SEPARATOR

DATA

MESSAGE UNIT

DATA SEPARATOR

ROOT SPECIFIER