Paradyne 3821PLUS manual 3821Plus AT Commands

AT Commands and S-Registers

Table 4-1

(1 of 13)

3821Plus AT Commands

*** ± AT Command Recovery Mode

Allows the modem to remain in Asynchronous data mode so that AT commands can be used to change the modem's current configuration. Use this command when AT commands are disabled or the modem is operating in Synchronous data mode.

This command can only be executed after the completion of a power-up self-test. Refer to Recovering AT Commands later in this chapter for procedures and guidelines on this command.

A / ± Repeat Last Command

Reexecutes the last command string. (Not to be preceded with AT or followed by pressing the Enter key.)

A ± Answer Mode

Allows the modem to go off-hook and attempts to establish a connection without waiting for a ring.

B ± ITU-T/Bell Mode

Determines the protocol used if the dial-line rate is set to 300 or 1200 bps. It has no effect if the rate is set to another value. (See %B.)

B, B0 V.21 or V.22 (300 or 1200 bps)

B1 Bell 103 or Bell 212A (300 or 1200 bps)

Dn ± Dial

Begins the dialing sequence. The dial string n (modifiers and telephone number) is entered after the D command.

Any digit 0±9, * , # , A, B, C, D, may be dialed as a DTMF tone. Only the digits 0±9 can be dialed in Pulse Dial mode.

The following example shows how to dial through a PBX. The dial string consists of the command string and the telephone number:

ATDT9,5551234

Command Telephone

String Number

Dial String

Modifiers include the following parameters:

T ± Tone (DTMF) dial. Any digit 0±9, * , # , A, B, C, or D can be dialed as tone.

P ± Pulse dial. Only the digits 0±9 can be dialed in Pulse Dial mode.

NOTE: Once a dialing method (tone or pulse) has been specified, it will remain active only until the end of that dial string. The factory setting is Tone dial.

,± Pause. Causes the modem to pause before processing the next character in the dial string. The length of this pause is determined by the value held in S-register S8, the Pause Time configuration option.

W ± Wait for dial tone. Modem waits for a second dial tone before processing the dial string. This can be the initial dial tone or a second tone received when dialing through a tandem PBX (for example, 9W555-6789), or when invoking special features (for example, 70#W555-6789, where 70# is the local telephone company command that disables Call Waiting).

3821-A2-GB20-40 January 1999 4-3