Subject: Re: is ANYONE running multiple vga cards right now.
To: None <email@example.com>
From: Michael C. Richardson <firstname.lastname@example.org>
Date: 08/27/1999 19:40:43
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>>>>> "Todd" == Todd Whitesel <email@example.com> writes:
>> Also, isn't VGA's video RAM always at 0xa0000? I even see that address
>> hardcoded in sys/dev/ic/vga.c. Makes it sound like it might be pretty
>> tough getting multiple cards running in text mode :(
Todd> You're right -- for ISA video cards.
Todd> But I'm talking about PCI video cards, which have to use address ranges
Todd> assigned to them by the BIOS.
Yes, but you see, video cards are allowed to break the PCI spec. Or,
rather the spec has an exception for them. They get to map themselves into
stock ISA VGA address memory as well as getting PCI address space assigned.
This is so that the system can boot, etc. and have video etc. without
a PnP aware OS --- e.g. DOS, Win3.11, OS/2.
:!mcr!: | Cow#1: Are you worried about getting Mad Cow Disease?
Michael Richardson | Cow#2: No. I'm a duck.
Home: firstname.lastname@example.org. PGP key available.
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