Chapter 3 - AT Commands

Chapter 3 - AT Commands (Win 98 Only)

Introduction

AT commands are the means by which you and your communications software are able to communicate with and configure your ISDN adapter. These commands enable you to establish, read and modify parameters associated with your ISDN connections, line protocols and call handling. The following provides a list of the AT commands recognized by Multi-Tech’s MultiModem ISDN terminal adapters.

Where indicated below, the AT prefix must be issued with the command. The AT command tells the modem “ATtention!, commands to follow”. If you issue AT as a command by itself, the adapter should respond OK, indicating that your cables are connected correctly and your baud rate is set properly.

AT commands are entered in HyperTerminal mode or can be issued as an extra setting for your connection. Use Start>Settings>Control Panel>Modems>ISDN Modem>Properties>Connection>Advanced>Extra settings.

Commands and Descriptions

ATA

Answer an incoming call

ATBn

Select protocol of transmission in B channel

ATB0

64K HDLC (default with universal modems under Win95)

ATB20

V.120 Async.

ATB21

V.120 Sync.

ATB3

X.75 Transparent, the same as ATB30 (default with ISDN X.75 Transparent modem under Win95)

ATB30

X.75 Transparent

ATB31

X.75 T.70 NL

ATB32

X.75 ISO 8208

ATB4

Async PPP to Sync PPP converter (default setting with Win95 Async to Sync PPP modem)

ATB41

Async to Sync PPP conversion in ML PPP mode, compatible with Microsoft ISDN Accelerator pack

ATB42

Async to sync PPP conversion to MLPPP

ATB43

Async to sync PPP conversion in MLPPP+BOD (bandwidth on demand)

ATB6

Async to sync PPP conversion over X.75 transmission

ATB61

Async to sync PPP conversion over X.75, but setting up secondary device in Dial-Up Networking

 

required.

ATB62

Async to sync PPP conversion in MLPPP over X.75

ATB63

Async to sync PPP conversion in MLPPP+BOD over X.75

ATDs

Dial a telephone number

ATDL

Dial the last number

ATD7693007

Dial telephone number 7693007

ATEn

Echo characters when in command mode

ATE0

Echo off

ATE1

Echo on ( default )

ATHn

On-Off Hook

ATH

On-Hook, Disconnect (same as ATH0)

ATH1

Off-Hook

ATI

Display version number, selected protocol, packet size, connected speed, MSN, and outgoing call

 

number.

ATO

On-Line command, switch to on-line from command mode

ATQn

Return the result code

ATQ0

Return the result code (default)

ATQ1

Does not return the result code

ATSr

Set or display the register value

ATS0=1

Set register 0 to 1, (S0=0 default, disable the auto-answer mode)

ATSr?

Display register content

MT128ISA/PCI

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