BNC 845-M - Manual (Page 14)

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Model 845-M Programmer’s Manual V1.1 2011
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.
Hierarchical Command Structure
All SCPI commands, except the common commands, are organized in a hierarchical structure similar
to the inverted tree file structure used in most computers. The SCPI standard refers to this structure
as “the Command Tree.” The command keywords that correspond to the major instrument control
functions are located at the top of the command tree. The command keywords for the Model 845-M
SCPI command set are shown below.
:ABORt
:DIAGnostic
:DISPlay
:INITiate
:OUTput
SOURce
:STATus