Paradyne 3910 operation manual AT Command Set and S-Registers, Operating Modes

AT Command Set and S-Registers 5

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1

Operating Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1

Switching Between Data Mode and Online Command Mode . . . . . . . . . 5-1

Escape Sequence and Escape Guard Time . . . . . . . . . . . . . . . . . . . . . . 5-2

Command Guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2

Result Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3

AT Command List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4

AT Command Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4

S-Register List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-14

S-Register Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-15

Overview

The AT command set provides an alternative method to the modem's DCP for entering commands that control the operation and configuration of the 391x Series modems. This chapter discusses guidelines necessary to operate AT commands as well as listing the modifiers for all AT commands supported by the 391x Series modems. AT commands are issued from asynchronous DTEs.

Operating Modes

The 391x Series modem has two operating modes, 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 Table 5-1 for a listing of result codes.)

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.

3910-A2-GN32-30 November 1996 5-1