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mnemonic, in which case the mnemonics are separated from each other by the colon (':'). For
instrument control commands, the mnemonics are specified by the SCPI standard, and indicate the tree
structure of the command set. The first mnemonic indicates the subsystem being controlled. Common
Command and Query Program Headers consist of a single mnemonic prefixed by an asterisk ('*').
The mnemonics consist of upper - or lower-case alpha characters. Mnemonics may be written in either
the long form, in which the entire mnemonic is written out, or the short form, in which only a specified
portion of the mnemonic is written out. Some mnemonics have only one form due to their short
length. Where a command is described, the portion appearing in upper case is the short form. Only the
short form or the long form may be used.
Example: The command to set the frequency to 1 kHz may be written in the following ways:
SOURCE:FREQUENCY 1KHZ
SOUR:FREQ 1KHZ
SOURCE:FREQ 1KHZ
Some mnemonics in a specified Program Header may be optional. This is indicated in the command
description by the mnemonic being enclosed in square brackets ([...]). This means it is not necessary to
write the mnemonic into the Program Header: it is a default condition. The 'SOURCE' mnemonic, for
example, is optional. Not specifying it will cause the device to search for the mnemonics in the Program
Header under the Source Subsystem. For example, the frequency may be set by the commands
FREQ:CW 1KHz
FREQ 1KHz
since the 'CW' mnemonic is also optional.
b)
Program Header Separator
The Program Header Separator is used to separate the program header from the program data. It
consists of one or more whitespace characters, denoted as <ws>. Typically, it is a space.
c)
Program Data
The Program Data represent the values of the parameters being set, for example, the '1KHZ' in the
above examples. Different forms of program data are accepted, depending on the command. The
Program Data types used in the instrument are:
i.
Character program data
This form of data is comprised of a mnemonic made up of lower - or upper-case alpha characters. As
with Program Header mnemonics, some Character Data mnemonics have short and long forms. Only
the short or the long form may be used.
ii.
Boolean data
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