SDB:WinModems and Linux
Version: 4.4 -
Symptom:
Your modem is not recognized in Linux or one or more of the following conditions match:
- It is an internal modem -- a card that can be plugged into the bus of a PC -- or it is an onboard card.
- It is an external USB modem.
- Drivers are only supplied for the Windows operating system, especially in the VXD format.
- The modem is nearly always Plug-and-Play capable.
- The motherboard BIOS is Plug-and-Play capable, too.
Plug-and-Play functions of the motherboard BIOS are not disabled for test purposes.
The BIOS of the computer displays only the previously existing internal or external serial ports, but not any additional port supplied by the card modem. - It is a PCI card that will be read out by the use of the command
/sbin/lspcias Communication Controller. - The modem has one of the following descriptions: HCF/HSF/HSP.
- Linux does not recognize the modem.
Cause:
The modem is a WinModem, which is not controlled by a serial port. The digital signal processor (DSP) on the board must be controlled directly by the main CPU.
There are well-defined command sets for modems, standardized by ITU (International Telecommunications Union, www.itu.ch) and TIA (Telecommunications Industry Association, www.tiaonline.org). The standards ITU V.250 and TIA/EIA 602 define the command set for a modem. The command sets have the ancient names: Hayes command set or AT command set.
Linux is able to handle modems complying with the standards mentioned above. WinModems do not comply with these standards and their interface details are not disclosed frequently.
A long list of modems including information about availability of drivers for Linux can be found under
http://www.linmodems.org/
Solution:
- Try one of the above-mentioned drivers.
- Replace the modem with a regular modem.
- Write a driver on your own or have someone write a driver.
<keyword>modem,windows,winmodem,at,command_set,v.250,tia.602,v.25.ter</keyword>