BNC 835-3 Programmer Manual - Manual (Page 13)

Berkeley Nucleonics
www.Berkeley Nucleonics.com
835-3
Programmer’s Manual v1.0
Page 13 of 37
Structure of a Command Line
A command line may consist of one or several commands. It is terminated by an EOI
together with the last data byte.
Several commands in a command line must be separated by a semicolon ";". If the next
command belongs to a different command system, the semicolon is followed by a colon.
A colon ":" at the beginning of a command marks the root node of the command tree.
If the successive commands belong to the same system, having one or several levels in
common, the command line can be abbreviated. To this end, the second command after
the semicolon starts with the level that lies below the common levels. The colon following
the semicolon must be omitted in this case.
Responses to Queries
A query is defined for each setting command unless explicitly specified otherwise. It is
formed by adding a question mark to the associated setting command. According to
SCPI, the responses to queries are partly subject to stricter rules than in standard IEEE
488.2.
Parameters
Most commands require a parameter to be specified. The parameters must be separated
from the header by a "white space". Permissible parameters are numerical values,
Boolean parameters, text, character strings and block data. The type of parameter
required for the respective command and the permissible range of values are specified in
the command description.
Numerical values Numerical values can be entered in any form, i.e. with sign, decimal
point and exponent. Values exceeding the resolution of the instrument are rounded up or
down. The mantissa may comprise up to 255 characters, the values must be in the value
range –9.9E37 to 9.9E37. The exponent is introduced by an "E" or "e". Entry of the
exponent alone is not allowed.
Units In the case of physical quantities, the unit can be entered. Permissible unit
prefixes are G (giga), MA (mega), MHZ are also permissible), K (kilo), M (milli), U
(micro) and N (nano). If the unit is missing, the basic unit is used.
Boolean Parameters Boolean parameters represent two states. The ON state (logically
true) is represented by ON or a numerical value unequal to 0. The OFF state (logically
false) is represented by OFF or the numerical value 0. ON or OFF is returned by a query.