Modem Interface
This combination card also has a modem that supports data
communication at up to 56 Kbps and fax communications at up to
14.4 Kbps. The on-board modem is compliant with nearly all of the
current standards for data/fax modems, such as V.90/K56flex
56 Kbps data protocols and Class 1 Group 3 14.4 Kbps fax
protocols.
The Cheetah Mini PCI Combo Adapter allows you to connect to
the Internet over standard phone lines, exchange information over
Bulletin Board Systems (BBS) and send and receive fax
messages like a standard fax machine. This card also allows you
to operate the modem in conjuction with Ethernet networking.
System Requirements
Before you install the Cheetah Mini PCI Combo Adapter, check
your system for the following requirements:
• A PC and BIOS that support the PCI Local Bus Specification
v2.0 or later
• An available bus-mastering type IIIA 32-bit Mini PCI slot
• An available telephone wall jack for modem connection
• A 10BASE-T/100BASE-TX switch or hub installed in your
network for connection to an Ethernet network
The Cheeah PCI Combo Adapter accepts standard AT commands
from the host PC to configure and control its modem functions.
Usually AT commands are sent to the modem by software
applications, so users have no need to input commands directly.
However, for modem testing and specific configuration, AT
commands can be entered from the keyboard using any terminal
communication software such as the Windows HyperTerminal
program.
AT commands must be entered in a particular format for the
modem to recognize them. A command always begins with the
letters “AT” (or lower case “at”), followed by one or more
commands and then <Enter>. The modem responds to an AT
command by sending a result code. An “OK” result means that the
command was executed. An “ERROR” result means that the
command was invalid.
Note that the modem must be in “command mode” or off-line to
accept AT commands. When the modem has established a
connection with another modem, it is on-line or in “data mode.” In
data mode any characters sent to the modem from the PC will be
transmitted to the remote modem and not interpreted as AT
commands.
When the modem is in data mode you can enter an escape code
sequence of “+++” to return it to command mode.
Connecting to the RJ-11 Port
The notebook’s RJ-11 port supports a standard telephone cable
connection. This port must be connected to an RJ-11 wall jack.
1. Attach the male RJ-11 connector on one end of a telephone
cable to the notebook’s RJ-11 port.
2. Attach the male connector on the other end of the cable
directly to an RJ-11 wall jack.
Modem Problems
• If there is no sound from the modem, check that your computer
speaker is working and that the volume is correctly set.
• If an “Error” message is displayed, or your modem is not
responding, check if you have selected the correct COM port in
your software set up.
• If the modem will not dial:
- check all phone line and cable connections and make sure
that you are using a standard analogue phone line.
- make sure that the parity, modem speed, word length and
stop bits are all set in accordance with your software’s
specifications.
• If the fax is not working, check if you have selected the correct
FAX class.
Troubleshooting With AT Commands
• If the modem can connect to some modems but not to others
you may have to enter AT commands directly. The following is
a table of possible commands to use. Note that, in this table,
“protocol” means error correction and data compression. The
first two entries are likely to be the most useful.
AT Command Function
To force different communication speeds
AT& F Negotiates speed and protocol (default
setting)
AT \N0 Negotiates speed only, not protocol (not
recommended)
AT \N3 Forces the protocol
AT-V90=1 S38=1
(default)
Dualmode (V.90 or K56flex)—5600 bps
AT-V90=0 K56flex only (disable V.90)—5600 bps
ATS38=0 V.90 only (disable K56flex)—5600 bps
AT-V90=0 S38=0 Disable both 56K and autorate on
V.34—3600 bps
AT S37=19 V.34—33600 bps
AT S37=11 V.32bis—14400 bps
AT S37=9 V.32—9600 bps
AT S37=6 2400 bps
AT S37=2 1200 bps
Other possible forced configurations
AT \N2 MNP 5 / MNP 4 operation
AT \N4 LAPM only
AT \N2 %C0 MNP 4 only
AT \N0 “Normal” operation: modem communicates
without error correction or data compression,
but retains speed buffering and auto-
negotiation of speed. This is not to be
confused with “standard“ configuration
AT S0=1 Auto-answer
Notes: 1.
When the protocol is forced, the modem will try to
communicate at the fastest speed available within the
forced protocol. It will not attempt to communicate using
other protocols
2.
To save all setup parameters in non-volatile memory:
type AT, followed by the parameter settings, followed by
&W and then press Enter.
3.
After having returned the modem to its default
configuration (using the AT &F command), and having
saved the setup parameters, use the ATZ command to
ensure that the modem receives your software’s
initialization string.
initialization string.
If the modem does not connect reliably at V.90, modify the
initialization string.
To do this in Windows 95 and 98:
1. Double-click “My Computer” on your desktop.
2. Double click “Dial-up Networking”.
