Black Box MD1641A manual PC Initialization Strings, Changing Default Parameters, AT &F X4 S0=0 M

SERIES II INTELLIGENT DATA/FAX MODEMS

3.4 PC Initialization Strings

We recommend the following initialization string for a Series II Modem connected to a PC-compatible computer when sharing a line with a telephone:

AT &F X4 S0=0 ^M

This string resets the Modem to the factory default settings, selects ex- tended result codes with NO DIAL TONE and BUSY, and turns off auto- answer. ^M must end every string sent to the modem from software.

It is the ASCII code for the RETURN key on most keyboards, and the default code for the carriage return character in the Modem and most communications programs. The carriage return character is defined in the Modem in S-register S3; if you change it, you must also change the carriage return character code used in your communications software. If you send a command directly to the modem in terminal mode rather than indirectly through communications software, you must end the command string by pressing the RETURN key (<CR>) instead of adding ^M to the string.

The following initialization string is for a Modem on a telephone line that functions solely as a DATA LINE:

AT &F X4 S0= 2 ^M

3.4.1 Changing Default Parameters

By default, the Series II Modem will answer after the first ring and try to communicate with a modem on the other end of the line. If you have one telephone line for voice, fax, and modem communications, the Modem may attempt to answer all incoming calls, voice as well as data. To change auto-answer to default off, open your communications program and type the following string in the terminal window:

AT &F S0=0 &F9 &W0 <CR>

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