Comtrol AT Command Set Rev A - Manual (Page 141)

AT Commands Reference Manual
100722B Conexant 3-115
3.4.3 Operation
Once the driver is loaded and the modem is connected to the cellular phone, and the
phone is powered on dial/answer functions will be routed through the phone instead of
the landline DAA, i.e., no special commands are needed to place or answer calls, the
same AT commands and software packages that are used for landline communication
sessions can be used. If the cellular phone is not connected or is powered off dial/answer
functions will be routed through the landline DAA, and if V.42 bis connection is
established the cellular phone driver will be purged so that the V.42 bis dictionaries can
be increased to their normal size.
While the modem is being used with a cellular phone it will respond with normal result
messages with the following differences in meaning:
NO DIAL TONE Indicates that cellular service is not currently available.
RING Indicates that the cellular phone is receiving an incoming call.
Modem Configuration
Modem performance will be improved by modification of your standard configuration; it
is recommended that the landline modem also be EC compatible for reliable
communications.
Cell Site AT&F
Base Site AT&F -SEC=1,18
MNP10-EC is automatically enabled on the cell side when a cellular phone driver is
loaded and the modem firmware detects that the cellular phone is attached, also in the
V.34 mode the modem is automatically configured to force the connection in V.32bis
mode.
On the cell side the transmit level is defined in the cellular driver, therefore it is not
necessary to set the level using the AT-SEC command.
In the V.34 mode, on the landline side, if MNP10-EC is disabled (AT-SEC=0), it will
automatically be enabled if another V.34 modem is calling (V.8 bis/V.8 signal indicates
cellular capability). No particular modulation will be chosen on the land line side.
Therefore if a landside V.34 modem is NOT going to receive any calls from a V.32bis
MNP10-EC modem it can be configured using AT&F -SEC=0,18 , otherwise use the
configuration above.
If MNP10-EC is enabled manually (using AT-SEC=1) no particular modulation will be
chosen, therefore if the user wishes to force V.32bis modulation they should use the
AT+MS=10,1,minspeed,maxspeed command (e.g., AT+MS=10,1,4800,12000 would
force V.32bis and limit the speed between 4800 and 12000 bps). To allow V.34
modulation use AT+MS=11,1,minspeed,maxspeed (e.g., AT+MS=11,1,4800,19200
would allow V.34 speeds between 4800 and 19200).
When MNP10-EC is enabled in V.34 modes the symbol rate is limited to 3000, therefore
the maximum speed would be 26.4K however the initial connect speed is limited to
21600.
If an AXCELL™ solution is used, a transmit level of -10dBm is required, therefore the
following initialization string should be used:
Cell Site AT &F -SEC=1,10