Checking Your Chipset for Linux Support

If you are not sure what kind of modem you have, examine the chipset on the card before you install it. Using that information, you can check out these websites for information on Linux modem support:

• Winmodems are not modems (http://start.at/modem)-To see if your PCI modem has a supported chipset, click Home Site, and then click the Chipset Database link. The site also contains a wealth of information on winmodems, other modem types (USB, ISA, and so on), and general modem operations.

• A Linmodems support page (linmodems.technion.ac.il)-Although it doesn't contain as large a database of supported modems as the previous site, the content here is very current (there are even references to Fedora).

Installing the Modem

The next step for a PCI modem is to install it and check it out, using the following instructions.

1. Physically install the modem-Follow the manufacturer's instructions for installing the modem. Make sure that you have:

   • Firmly seated the modem in the PCI slot

   • Replaced the screw holding the modem to the case (if appropriate)

   • Plugged the line jack on the modem to your telephone wall jack

2. Boot Linux-During the boot process, the kudzu utility checks the /etc/sysconfig/hwconf file to look for any hardware that has been added or removed since the computer was shut down.

   In this case, kudzu should find the new modem installed in one of your PCI slots and offer to let you configure it. Figure 13-1 shows an example of a kudzu screen where a supported Multitech modem is detected; in Figure 13-2 a nonsupported winmodem is detected:

   Note

   If you are booting to runlevel 5 (the default state), a graphical screen is shown during startup. You need to click Show Details to be able to see the kudzu screen when it appears.

   In Figure 13-1, you can see that a modem containing the supported Lucent Venus chipset was detected. In Figure 13-2, kudzu can tell that the device is a modem from Motorola, but it does not have a driver to support the device. In both cases, you are prompted for a response.

3. Configure Modem in Kudzu-From the kudzu screen, click Configure. Kudzu will try to add your modem to the local /etc/sysconfig/hwconf file (which contains information defining all the hardware on your computer).

Figure 13-1: During boot-up, kudzu finds a supported Multitech modem with a 4Lucent Venus chipset.

Figure 13-2: Here kudzu finds a nonsupported Motorola winmodem.

Checking the Modem

At this point, if the modem was properly detected you should be able to list information about that modem. Here's how:

1. List PCI devices-Once the computer starts up, type the following to list all the PCI devices connected to your computer (presumably including the modem you installed).

   # /sbin/lspci -vv | less
   

   Page through the output (use the space bar) to view the hardware connected to your PCI slots. Here's an example of output for a PCI modem:

   00:09.0 Communication controller: Lucent Microelectronics
           Venus Modem (V90, 56KFlex)
      Subsystem: Lucent Microelectronics: Unknown device 5656
      Control: I/0+ Mem+ BusMaster+ SpecCycle- MemWINV-
        VGASnoop- ParErr- Stepping- SERR- FastB2B-
      Status: Cap+ 66Mhz- UDF- FastB2B+ ParErr-
        DEVSEL=medium>TAbort- <TAbort- <MAbort- >SERR- <PERR-
      Latency: 0 (63000ns min, 3500ns max)
      Interrupt: pin A routed to IRQ 10
   

   In this case, the modem is a MultiTech MT5634ZPX-PCI. Key information is that it is a PCI modem that includes the Lucent Venus chipset. (That is one of a handful of chipsets you can find on internal PCI modems that are controller-based.)

   The lspci output from the winmodem I tested gave less information about the modem:

   00:09.0 Communication controller: Motorola:
          Unknown device 5608
     Subsystem: Motorola: Unknown device 0000
     Flags: bus master, medium devsel, latency 32,IRQ 10
     I/0 ports at ec00 [size=256]
     Memory at dffff000 (32-bit, non-prefetchable) [size=4K]
     Capabilities: [40] Power Management version 2
   
   

   This winmodem contained the Motorola 62412-51 chip, which I had to determine by physically looking at the card. By checking the Chipset Database at the http://start.at/modem site and selecting the Motorola SM56 PCI link, I could see that there was support for that Motorola chip through Red Hat Linux 7.1, but that modems with that chipset were not supported for later systems.

2. Run scanModem-To get more information about your PCI modem, download the scanmodem utility and run it. This utility gives you information about any PCI modems it finds (winmodems or not) and will give you any Fedora-specific information it has about modem drivers.

   1. Change to the directory in which you want to save the scanmodem utility and type the following:

      # wget http://linmodems.technion.ac.il/packages/scanModem.gz
      

   2. Unzip the utility by typing gunzip scanModem.gz

   3. Run the utility by typing sh scanModem

   4. Read the ModemData.txt file (for information specific to Fedora and your modem), ModemData.txt.2 (for general scanModem information), and ModemDriverCompiling.txt (to compile your own winmodem driver).

3. Continue-Where you go from here depends on whether or not you have a controller-based or controller-less modem:

   • Winmodem-If you have a winmodem and are still determined to try to get it working, refer to the "Using Winmodems" sidebar and Table 13-2 for further information. They will help you understand what you need to do to get your winmodem working (if that's possible).

   • Controller-based PCI modem-With a supported controller-based PCI modem, Linux should automatically know to use the serial.o driver to provide a serial interface to the modem. Therefore, to Linux, the modem is configured to be used via a standard serial port (/dev/ttyS0, /dev/ttyS1, and so forth).

The next step is to make sure that Linux can find your modem and communicate with it. For that, skip ahead to the Probing and Trying your Modem section, given later in this chapter.