On 8/22/06, James Richard Tyrer <[EMAIL PROTECTED]> wrote:
> On another topic, it is possible to build a graphics card without VGA
> support and a ROM. It's not like you are trying to run Windows on
> these cards. Anyone interested enough to acquire one of these cards
> can switch to a custom GRUB and kernel video driver that don't use
> VGA. Most Macs don't have VGA support and no one ever notices when
> they run Linux on them.
The problem is that PC MotherBoards expect VGA to boot and _configure_.
Not being able to configure your MotherBoard (and not being able to
see the error messages) is like a major issue. Now if they were all
well behaved and always used the Video BIOS calls, it would be no
problem -- the problem is that we are dreaming if we think that. The
easiest solution is to just use a VGA core. We could start with the one
from Open Cores:
The kind of people likely to buy this card would just plug in another
graphics card if they were having trouble with their system BIOS. Some
may even run LinuxBIOS and modify it to use the card. Lack of VGA can
be worked around if it is a lot of trouble to build the electronics
supporting it. Note that Macs don't support VGA. Just let the machine
boot headless until the OS driver loads, or write a version of GRUB
that can talk to the card.
The Voodoo cards only function in 3D mode. You have to have a VGA card
in the system too. I believe they daisy chain the video cables so that
a single monitor works. You plug the VGA output into the Voodoo and
then run video out from the Voodoo to the monitor. When the Voodoo
card first boots it is passive and the video passes through.
VGA cards can be had for under under $25, daisy chaining may be
something to consider.
http://www.opencores.org/projects.cgi/web/vga_lcd/overview
or we could use a commercial VGA core. Either way, we could concentrate
on the 3D stuff and not waste time reinventing the wheel.
--
JRT
--
Jon Smirl
[EMAIL PROTECTED]
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