serial ports

Magnus Hiie (Mgn@ekspress.ee)
Mon, 5 Aug 1996 13:17:49 +0200


Hi!

I'm sorry, if this is a newbie question, but:

Why is it impossible for multiple (standard) serial ports (ttyS?) to
use the same IRQs?

If the ports are used one by one (a process opens a port, does smth
with it, closes it), they can be on the same IRQ. But this can't be
done using these IRQ sharing ports at the same time (overrun errors).

If I remember correctly, I once did smth like this when I used DOS.

Is it some hardware limitation or what? When an interrupt occurs,
serial driver could look up which port it was meant for, couldn't it?

*********************************
Magnus Hiie
Computer Manager
Eesti Ekspress
E-mail: mgn@ekspress.ee
Tel: +372 6408046
GSM: +372 56 51146