BNC 835 Programmer Manual - Manual (Page 17)

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— SCPI required commands
— SCPI optional commands (per SCPI 1999.0)
— SCPI compliant commands that are unique to the BENCHTOP MICROWAVE SOURCE. Not
all of the commands supported by the instrument are taken from the SCPI standard; however,
their syntax follows SCPI rules.
4.3 SCPI Command Syntax
Typical SCPI commands consist of one or more keywords, parameters, and punctuation. SCPI
command keywords can be a mixture of upper and lower case characters. Except for common
commands, each keyword has a long and a short form. In this manual, the long form is presented with
the short form in upper case and the remainder in lower case. Unrecognized versions of long form or
short form commands, or improper syntax, will generate an error.
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.