Re: Question: Multiple Super Serial Card ][s in //e?

[david@uow.edu.au (David Wilson)]

"Mark Cummings" <NOTfigjams@primus.com.au> writes:
>What annoys me the most on the PC is that manufacturers of cards only
>normally allocate a choice of a few IRQ's for a particular card(s). I have
>tried to free up some unused IRQ's so that other cards could use them, but
>keep running into the problem that the other cards don't have that IRQ as a
>choice. For example try to free up IRQ6 if you remove your floppy drive or
>IRQ15 if you're only using 1 IDE port, and you'll be lucky if you can use
>that IRQ for another card as it's not a hardware option.

I agree. PCI is better in that the card uses whatever the BIOS gives it
(in general - legacy sound card support often requires particular IRQs).
Unfortunately my BP6 will not assign IRQ6 to the PCI bus (having freed it
by using an LS-120 instead of a floppy). Usually IRQ12 will go to PCI if
you disable the PS/2 mouse. In fact 3,4,5,7,9,10,11,12,14 & 15 will normally
be usable by PCI cards if you disable COM or LPT or mouse or IDE ports.
Typically only 4 IRQs will be routed to the PCI bus so some sharing often
occurs.
--
David Wilson  School of IT & CS, Uni of Wollongong, Australia