B-2 APPENDIX B: ALPHABETIC COMMAND SUMMARY
With the exception of the Dial options, modems ignore any commands issued after D in the same command string.
Bn Set handshaking options.
B1 Bell answer tone. This setting selects HST
modulation, but use it only if the modem is
not required to answer V.34-type calls.
Cn Enable or disable the transmitter.
C0 Transmitter disabled; for receiving only.
C1 Transmitter enabled.
Command Function
Dn Dial a phone number and issue other optional commands.
The numbers 0-9 are accepted. The maximum number of
characters allowed is 36, including the AT prefix, punctuation,
and spaces.
Optional parameters:
P Dial using pulses. Accepted but ignored.
TDial using tones. Accepted but ignored.
,(Comma) Pause for 2 seconds (or the time in
S-Register 8). Accepted but ignored.
;(Semicolon) Remain in Command mode after
dialing.
" Dial the letters that follow.
WWait for a second dial tone before continuing
dialing (with X3 or higher). Accepted but
ignored.
@Wait for an answer (with X3, X4, or X7).
Accepted but ignored.
/Pause for 125 milliseconds. Accepted but
ignored.
RReverse frequencies. Use this command
when calling an originate-only modem. It
forces the modem to dial out at the answer
frequency.
Command Function