Product data

USRobotics
Command Reference
Syntax and Procedures - 4
character may not appear in the body. The modem can accept at least 80
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.
Repeating a Command Line
If the prefix "A/" or "a/" is received, the modem immediately executes once again
the body of the preceding command line. No editing is possible, and no
termination character is necessary. A command line may be repeated multiple
times in this manner. Responses to the repeated command line are issued using
format of the original command line. If "A/" is received before any command line
has been executed, the preceding command line is assumed to have been empty
(that results in an OK result code).
Types of DTE Commands
There are two types of commands: action commands and parameter commands.
Commands of either type may be included in command lines, in any order.
Action commands may be "executed" (to invoke a particular function of the
equipment, which generally involves more than the simple storage of a value for
later use), or "tested" (to determine whether or not the equipment implements the
action command, and, if subparameters are associated with the action, the ranges
of subparameter values that are supported).