CXR V.34bis series, Руководство по эксплуатации и установке

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V.34bis Series Standalone & Rackmount Modems 19
3
Modes and Configurations
Common Operations
The AJ Modems are typically operated using the industry-standard AT
command set. The AT commands for these modems have been expanded
beyond the standard set in order to incorporate the many additional
features that are included in these modems. AT commands are issued to
the modem in Command Mode. The modem is in Command Mode when it
is disconnected from the phone line. This is sometimes referred to as the
Idle Mode.
An asynchronous communication program eliminates the need to learn the
modem commands. All AT commands, except A/ and the escape code
(+++) begin with the letters AT, meaning "attention". Several commands
may share a line as a single string of commands, but only one AT prefix is
required, at the beginning of the line. Each command consists of the
following elements:
•
The two character sequence
AT
•
A command
•
A command parameter (optional)
•
A carriage return
Example:
To enter the command 'Answer', type
ATA
and <enter>.
If the subscript n = 0 is desired it is not necessary to type the "0".
If the n
position is left blank the modem assumes a "0".
Table 6.2 provides the
full details of the AT commands.
Some commands do not have parameters. Any missing parameter in a
command is assigned the value zero, which may be a valid parameter for
the command. The sequence followed by AT command causes the modem
to enter a command state. That is, AT without a command serves as a
wake up code and an "OK" appears on the screen.
The modem queues commands in a 40-character command line. The
command line beginning with AT can have several commands. A separator
is not required between the commands. The command line format is:
AT command (parameter)...
(enter)