If you use an older ISA or EISA bus device, you will need to configure it.
Unlike PCI, IDA devices do not automatically configure their IRQs, I/O
addresses, etc.

Just before the PCI bus became the standard, a way was found to automatically
configure ISA devices, called "Plug-and-Play", or "PnP".  This standard
didn't work very well at all and earned the nickname "Plug-and-Pray".   It
works slightly better on Windows than on Unix or Linux.

If you have such a computer then you will want to or need to set up PnP.  First
you will need to install the "isapnptools" package.  Then the steps to
use the tools in this package are:

If the system is dual-booted with Windows, use the Windows device manager
to see the values for your ISA-PnP devices, such as internal modems and
sound cards.  Record those values someplace.

Save /etc/isapnp.conf if there is one:
   # mv /etc/isapnp.conf /etc/isapnp.conf.old

Make a new one:
   # pnpdump > /etc/isapnp.conf

Uncomment the resources for your modem and sound card as you got them
from Windows:
   # vi /etc/isapnp.conf

Load the settings:
   # isapnp /etc/isapnp.conf

If configuring an ISA-PnP modem, you need to tell the device driver
what settings your modem is using.  For instance, if you set the
modem on IRQ 11, then:

   # setserial /dev/ttyS0 irq 11