Product data

USRobotics

Command Reference

Data Command Set - 17

Data Command Set

Command Guidelines

The commands used to control and report modem operation in data modem mode

are defined in this section.

The Data Modem Mode commands and responses described in this section are

applicable when command +FCLASS=0. (See +FCLASS for the definition of the

FCLASS command.)

The default values are typical of a fully configured modem supporting all data

rates and options. The actual default value is dependent upon modem software as

defined by the .INF File.

Commands are accepted by the modem once the previous command has been

fully executed, which is normally indicated by the return of an appropriate result

code. Execution of commands D and A, either as a result of a direct command or

a re-execute command, will be aborted if another character is entered before

completion of the handshake.

Escape Code Sequence

When the modem has established a connection and has entered on-line data

mode, it is possible to break into the data transmission in order to issue further

commands to the modem in an on-line command mode. This is achieved by the

DTE sending to the modem a sequence of three ASCII characters specified by

receipt of the last character of the three escape character sequence from the DTE

and sending of the OK result code to the DTE is controlled by the S12 register.

Data Commands

The modem will respond to the commands detailed below. Parameters applicable

to each command are listed with the command description. The defaults shown

correspond to default values provided in the .INF File.

Generic Modem Control

Z - Reset to Default Configuration

This command instructs the modem to reset to default values as altered by non-

volatile parameter storage. If the modem is connected to the line, it will be

disconnected from the line, terminating any call in progress.