Telenetics 56 - Manual (Page 32)

AT Commands
Page 24
Command Line General Format
A command line is made up of three elements: the prefix, the body, and the termination
character.
The command line prefix consists of the characters "AT" or "at". To repeat the execution
of the previous command line, the characters "A/" or "a/" are used without typing the
command line prefix.
The body is made up of individual commands described in this document. Space
characters (IA5 2/0) are ignored and may be used freely for formatting purposes, unless
they are embedded in numeric or string constants. The termination character may not
appear in the body. The modem can accept at least 50 characters in the body.
The termination character may be selected by a user option (parameter S3), the default
being CR.
Command Line Editing
The character defined by parameter S5 (default, BS) is interpreted as a request from the
DTE to the modem to delete the previous character. Any control characters (IA5 0/0
through 1/15, inclusive) that remain in the command line after receipt of the termination
character are ignored by the modem.
The modem checks characters from the DTE first to see if they match the termination
character (S3), then the editing character (S5), before checking for other characters. This
ensures that these characters will be properly recognized even if they are set to values
that the modem uses for other purposes. If S3 and S5 are set to the same value, a
matching character will be treated as matching S3 (S3 is checked before S5).
Command Line Echo
The modem may echo characters received from the DTE during command state and
online command state back to the DTE, depending on the setting of the E command. If
enabled, characters received from the DTE are echoed in the same format as received.
Invalid characters in the command line or incomplete or improperly formed command
line prefixes may not be echoed.