Chroma 61501, Руководство пользователя

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Programmable AC Source 61501/61502/61503/61504 User’s Manual
8-4
8.3.5 Basic Definition
Command Tree Table:
The commands of the AC source are based on a hierarchical structure, also known as a tree
system. In order to obtain a particular command, the full path to that command must be
specified. This path is represented in the table by placing the highest node in the farthest
left position of the hierarchy. Lower nodes in the hierarchy are indented in the position to
the right, below the parent node.
Program Headers:
Program headers are key words that identify the command. They follow the syntax
described in subsection 8.6 of IEEE 488.2. The AC source accepts characters in both
upper and lower case without distinguishing the difference. Program headers consist of two
distinctive types, common command headers and instrument-controlled headers.
Common Command and Query Headers:
The syntax of common command and query headers is described in IEEE 488.2. It is used
together with the IEEE 488.2-defined common commands and queries. The commands
with a leading “ * ” are common commands.
Instrument-Controlled Headers:
Instrument-controlled headers are used for all other instrument commands. Each of them
has a long form and a short form. The AC source only accepts the exact short and long
forms. A special notation will be taken to differentiate the short form header from the long
one of the same header in this subsection. The short forms of the header are shown in
characters of upper case, whereas the rest of the headers are shown in those of lower case.
Program Header Separator (:):
If a command has more than one header, the user must separate them with a colon
(FETC:CURR?, VOLT:DC 10). Data must be separated from program header by one space
at least.
Program Message:
Program message consists of a sequence of zero or more elements of program message
unit that is separated by separator elements of program message unit.
Program Message Unit:
Program message unit represents a single command, programming data, or query.
Example: FREQ?, OUTPut ON.
Program Message Unit Separator ( ; ):
The separator (semicolon ;) separates the program message unit elements from one another
in a program message.
Example: VOLT:AC 110 ; FREQ 120<PMT>