Tektronix AFG2021 Programmer's Manual page 21

AFG2021 Arbitrary Function Generator Programmer Manual
Table 2-2: Command message elements
Symbol Meaning
<Header>
The basic command name. If the header ends with a question mark, the
command is a query. The header may begin with a colon (:) character;
if the command is concatenated with other commands the beginning
colon is required. The beginning colon can never be used with command
headers beginning with a star (*).
<Mnemonic> A header subfunction. Some command headers have only one mnemonic.
If a command header has multiple mnemonics, they are always separated
from each other by a colon (:) character.
<Argument> A quantity, quality, restriction, or limit associated with the header. Not
all commands have an argument, while other commands have multiple
arguments. Arguments are separated from the header by a <Space>.
Arguments are separated from each other by a <Comma>.
A single comma between arguments of multiple-argument commands. It
<Comma>
may optionally have white space characters before and after the comma.
A white space character between command header and argument. It may
<Space>
optionally consist of multiple white space characters.
The following figure shows the five command message elements.
Commands. Commands cause the instrument to perform a specific function or
change one of its settings. Commands have the structure:
[:]<Header>[<Space><Argument>[<Comma><Argument>]...]
A command header is made up of one or more mnemonics arranged in a
hierarchical or tree structure. The first mnemonic is the base or root of the tree and
each subsequent mnemonic is a level or branch of the previous one. Commands at
a higher level in the tree may affect those at a lower level. The leading colon (:)
always returns you to the base of the command tree.
Queries. Queries cause the instrument to return information about its status or
settings. Queries have the structure:
[:]<Header>?
[:]<Header>?[<Space><Argument>[<Comma><Argument>]...]
Command Syntax
2-3