IBM Aptiva, Hardware Handbook

Page: 41 / 136

Modem commands 31
Modem commands
Table 3 lists the modem commands you are likely to use most often. The built-in modems are compatible with the
Hayes AT command set. All commands in this table must be preceded by the letters
AT unless otherwise indicated. Not
all of the AT commands are listed here.
For example, locate Ds in the Code/Command column of Table 3. To tell your modem to dial a telephone number using
touch-tone dialing, type ATDT followed by the telephone number and then press Enter . The complete command might
look like this: ATDT5554242 . To dial the same telephone number using pulse dialing, you would type
ATDP5554242 . Spaces are not required in the commands unless otherwise indicated.
Table 3: Modem commands
Code/Command Function
AT Begins the command line. The modem is ready to accept a command.
A/ Repeats the last command given, if it is not preceded by AT or followed by a carriage return.
A Answers the call immediately.
Ds The modem automatically dials a telephone number “ s ” where “ s ” is a complete telephone number. The command may
also include the following codes:
s=P Pulse dialing
s=R Dial an “originate-only” modem
s=T Touch-tone dialing
s=, Pause while dialing
s=@ Wait 30 seconds for a valid ringback followed by 5 seconds silence before next symbol
s=; Return to command state after dialing
s=! Go off-hook 0.5 seconds
s=W Wait for dial tone
Ds=n Dials one of four stored telephone numbers.
En Sets Echo on or off
n=0 Echo off
n=1 Echo on