Tektronix 2714, Руководство программиста

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Instrument-Specific Message Structure
2–12
2714 & 2715 Programmer Manual
hundreds of data words in a single argument called a binary block.
SET?
is a
special query that returns many arguments separated by semicolons (;) so the
response can be read back to the spectrum analyzer as a series of commands.
The 2714 or 2715 understands uppercase letters, lowercase letters, or a mixture
of upper and lowercase letters in command and query headers. Our examples use
the long form of command and query headers. However, most (but not all)
command and query headers can be written using only the first three letters. That
is,
FRE
means the same as
FREq
and
FOF
means the same as
FOFfset
.
As you become more familiar with the commands and queries, you will find that
the shortened forms are quicker to use. However, the long forms are easier to
read and are always used by the instrument in response headers.
Throughout the remainder of this manual the long form for headers will be used.
The required letters will be capital letters and the optional characters will be
lowercase letters. These examples show how headers will appear in this manual:
FREq
VRTdsp
MAMpl
You can also use variations of the short and long header forms.
VRT
,
VRTd
,
VRTds
, and
VRTdsp
are all acceptable header forms for the vertical display
command or query.
The space character is used to separate a command or response header from its
first argument, or to separate the question mark (?) following a query header
from its argument. The space is optional when there are no arguments.
Commas are used to separate or delimit multiple arguments in commands and
responses. They should not be used elsewhere.
Semicolons are normally used to separate or delimit multiple message units in a
single message. They may also (optionally) follow the last argument of a
command or query. They should not be used elsewhere. The line feed character
can be substituted for the semicolon.
Colons are used to connect the two parts of a linked argument. They should not
be used elsewhere.
Headers
Space ( )
Comma (,)
Semicolon (;)
Colon (:)