KEPCO TMA 4882-27 - Manual (Page 38)

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TMA 4882-27 021910
3.6.4.2 KEYWORD SEPARATOR
If a command has two or more keywords, adjacent keywords must be separated by a colon (:)
which acts as the keyword separator (e.g., CURR:LEV:TRIG). The colon can also act as a root
specifier (paragraph 3.6.4.7).
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
Some data is required to be boolean. Boolean data represents either an on or off condition. The
TMA 4882-27 accepts either ON or 1 for the true (on) state and either OFF or 0 for the false (off)
state (e.g. OUTPUT OFF is the same as OUTPUT 0).
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
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 3-2) 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.
3.6.5 ADDRESSING MULTIPLE POWER SUPPLIES
Power supplies on the IEEE 1118 bus are selected by node address, also referred to as node
number or channel number. Refer to the applicable manuals for the power modules connected
to the IEEE 1118 bus to set each power module to a unique node number, from 1 to 31 (a maxi-
mum of 27 power modules may be connected to the bus).