FreeBSD  Release  12.0  Install  Guide



Internal PCI Voice modem

Sometimes the GENERIC kernel cannot identify your internal modem and lists the offending PCI modem card as (unknown card) in the /var/run/dmesg.boot log. This problem can also be caused by PCs with pre-Y2K BIOS.

pci0: <unknown card> (vendor=0x1106, dev=0x3050) at 7.3

You will also get this message if your PCI modem is a Winmodem. Very seldom is the PCI modem physically labeled or marked as a Winmodem. Read the marketing information on the box your PCI modem came in, or check out the support web site for the PCI modem's manufacturer to verify it's a Winmodem. If your PCI modem is a Winmodem, replace it.


PCI Modem found as <unknown card>

Try the pciconf -lv command to see if it gives you any useful info.

Some older PCs have BIOS which cannot correctly ID PCI modems. Your only remaining option is to customize the kernel source by adding the following device statement at the end of the kernel source and then recompiling.

device puc

This kernel option enables the 'puc' (PCI Universal Communications) driver which does additional probing during the boot process to help connect PCI-based serial ports to the 'sio' driver. I have not found a situation on desktop PCs where this did not fix the PCI modem <unknown card> problem, as long it’s not a Winmodem.


PCI Modem found and moved to sio4

When the boot probe process finds a PCI modem it automatically moves it to sio4 as the dmesg.boot messages shows below.

sio0: <Zoom PCI Modem> port 0xe400-0xe407,0xe000-0xe0ff,
mem 0xe2000000-0xe20000ff irq 3 at device 19.0 on pci0
sio0: moving to sio4
sio4: type 16550A

Sio4 is internal device cuaa4 and com5.


Determining if your internal PCI modem is

connected to FBSD

You are going to use the 'tip' command to test if FBSD can communicate with your modem. This test will verify that FBSD can connect to the PCI modem and also that it will respond to the Hayes commands you will issue to it.

The ‘tip comx’ command uses the /etc/remote file for the definition of comx. I have listed the whole group of comx statements here from the /etc/remote file for reference so you can see how the siox/comx/cuaax relate to each other.

# Finger friendly shortcuts

On the command line enter:

tip com5      # com5 is your PCI modem


is displayed meaning 'tip' has made contact with the PCI modem.

Type AT and then hit enter.   'AT' is the Hayes attention command.

'OK'    is displayed.

This means the Hayes attention command was received by the modem and issued its normal reply of 'OK'. Your modem configuration has passed the test and is functional.

You now have to ‘train’ the modem to use 115200 as the internal default baud speed. Enter the ‘AT’ Hayes command 10 times. You will receive the ‘OK’ reply from the modem each time. This is a very important step that has a very large impact on the performance of your modem's throughput. Do not bypass this step.

Use the keyboard ~ key followed by the . key to exit tip.

Remember, device ‘cuaa4’ is the device you tell ‘user ppp’ to use.


NOTE:  If you get this message;

Interrupt storm detected on irqX:,  throttling interrupt source.

This means your PCI modem is sharing it's interrupt with another expansion board in your PC. Try moving the PCI modem card to different expansion slots on the motherboard until its not sharing it's IRQ with anything.


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