Command And Data Modes - Paradyne COMSPHERE 3920Plus Technical Reference Manual

AT Command Set and S-Registers
Overview
In Singleport mode, the AT command set provides an alternative method to the modem's DCP for
entering commands that control the operation and configuration of the 392xPlus modems. This
chapter discusses guidelines necessary to operate AT commands as well as listing the modifiers for
all AT commands supported by the 392xPlus modems. AT commands are issued from
asynchronous DTEs.

Command and Data Modes

AT commands enable you to operate in Command mode and Data mode. Before a modem goes
online (establishes a successful connection with a remote modem), it is considered to be in
Command mode; an idle state where you can modify its operating parameters or issue modem
commands. (Any command issued is acknowledged with a response in either words or digits
known as Result Codes. Refer to
Once the modems are online, either by answering or originating a call, they automatically switch to
Data mode. Data mode is a state where any entries made from the DTE are considered data and are
transmitted and received between modems. The modems remain in Data mode until the connection
is broken or until they are forced into online Command mode using the escape sequence (+++).
Switching Between Data Mode and Online Command Mode
Sometimes it is necessary to change operating parameters while the modems are online. The
Escape Sequence allows you to toggle the modem between Data mode and online Command mode
while maintaining a connection with the remote modem. This is accomplished using the escape
sequence to exit Data mode and the O command to return to Data mode.
3920-A2-GH30-40
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Command and Data Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Switching Between Data Mode and Online Command Mode
Escape Sequence and Escape Guard Time
Command Guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Result Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
AT Command List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
AT Command Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
S-Register List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
S-Register Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 14-1
October 1998
. . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . .
for a listing of result codes.)
14
14-1
14-1
14-1
14-2
14-2
14-3
14-5
14-5
14-16
14-16
14-1