We have been given an old Intel PCI mother board with socket 4, AMI BIOS
from 1992, a 60 MHz Pentium CPU with bug, 2 x 4 MB PS/2 SIMMs, Cirrus
Logic SVGA on board, I/O on board. Using an old mini tower case and an
80 MB Seagate hard disk I've built a working PC from it which runs Linux
2.0.33. The only card in that PC is a 16 bit ISA WD8003 ethernet card
(IRQ 11 and shared memory are registered in BIOS).
Everything runs fine except for my attempts to connect a mouse. I've
tried several mice, all of which work perfectly in other PCs. Regardless
whether I connect it to COM1 or COM2 (which are both enabled in BIOS and
use IRQ 4 and 3, respectively) there are no characters on cua0 nor on
cua1. On other PCs running Linix I can send a whole bunch of characters
to the console with cat /dev/cua0 (or cat /dev/cua1) when moving the
When I'm running gpm on either of the two serial ports the respective
number of interrupts (listed in /proc/interrupts) does not increase when
moving the mouse or pressing a mouse button. Only on plugging in or
unplugging the mouse does the respective interrupt count increase by
one. This behaviour is identical for all three mice tested (which run
fine on other PCs).
I've then disabled in BIOS the on board I/O and plugged in a 16 bit ISA
I/O card on which everything except for the two serial ports was
diabled. I got exacly the same behaviour. I've also removed the ethernet
card, which did not make any difference though. Even unplugging the disk
drives didn't make a difference.
Anybody got an idea what the reason for this strange behaviour could be?
Some kind of address conflict? I'd be very glad about any hints to this
really annoying problem. Thanks.
Institut fr Theoretische Physik +49 30 314-24254, FAX -21130
Technische Universit?t Berlin http://home.pages.de/~schwarz/