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Rerouting PCI interrupts to legacy interrupts

Posted: Thu Feb 10, 2022 1:37 pm
by Award
Hi, first post here. I searched the site but found nothing relevant. I'm not always good at searching.

If it's possible I want to configure a fairly old PC which has only PCI slots to use the legacy interrupts IRQ3 and/or IRQ4 for PCI multi-serial-port expansion cards.

The software which wants to use those IRQs is a business suite which can handle many serial ports but expects their interrupts only on IRQ3 and 4. It was originally installed on a box with ISA slots but the box recently died and has been replaced by a slightly younger one. This replacement PC uses a Phoenix Award BIOS but if there's a general approach which is independent of the BIOS provider that would be great. The BIOS does have some options for configuring PCI/legacy interrupts but I don't think this will do what I want. Someone here may be able to tell me I'm wrong about that.

As long as it's reliable it doesn't matter to me if it's a BIOS settings change, a BIOS tweak, a BIOS replacement, or some add-on, or a driver but obviously the lower the risk the better.

The operating system is MS-DOS 6.22.

Thanks for reading.