On Wed, Oct 16, 2002 at 06:36:23PM +0200, Johan Danielsson wrote:
> Ken Hornstein <kenh@cmf.nrl.navy.mil> writes:
> 
> > There are some video cards that use the com3 I/O space, and when the
> > com probe routine tries to probe for com3, the card gets in a mode
> > where it doesn't display anything (I have one of these cards).
> 
> I think the issue is
> 
> com0	at isa? port 0x3f8 irq 4	# Standard PC serial ports
> com1	at isa? port 0x2f8 irq 3
> com2	at isa? port 0x3e8 irq 5
> #com3	at isa? port 0x2e8 irq 9
 
> I suppose one reason to use com0 instead of com* is to make sure these
> ports are exactly that.

I'd suggest sticking with the above config. Some/many machines have
BIOS settings to turn off selected serial ports. It would be a shame
to introduce the "jumping serial port" problem that we also have with
hard disks. 
-- 
Kevin P. Neal                                http://www.pobox.com/~kpn/

"It sounded pretty good, but it's hard to tell how it will work out
in practice." -- Dennis Ritchie, ~1977, "Summary of a DEC 32-bit machine"