B-4 APPENDIX B: AT COMMANDS, REGISTERS, AND RESULT CODES
AT Command Set for Internal Analog Fax Modem

Table B-1 summarizes the AT command set for the internal

analog modem.

Table B-2 AT Command Set Summary for the Internal Analog Modem
Command Function (Example) Description
BSet 1200 bps (operation= 0) Initiates calls using either ITU-T V.220 or
Bell 212a at 1200 bps.
0 — V.22
1 — Bell 212a (default)
C1 ATC1 Modem responds with OK
F Select modem modulation mode 0 — Auto detect (default)
1 — V.21/Bell 103
3 — V.23
4 — V.22/Bell 212a
5 — V.22bis
6 — V.32bis/V.32 4800 bps
7 — V.32bis/V.32 7200 bps
8 — V.32bis/V.32 9600 bps
9 — V.32bis 12000 bps
10 — V.32bis 14400 bps
L Modem speaker volume control 0,1 — Low
2 — Medium (default)
3 — High
M Modem speaker operation 0 — Off
1 — On during handshaking, off while
receiving carrier (default)
2 — On during handshaking, on while
receiving carrier
3 — Off while receiving carrier, on
during answering
(continued)