Framebuffer or standard VGA ?

ollie lho ollie at sis.com.tw
Tue Sep 10 21:15:00 CEST 2002


On Wed, 2002-09-11 at 00:27, Steve M. Gehlbach wrote:
> I am hoping to get standard alphanumeric vga setup into the linuxbios code
> base, as part of the stpc initialization, in the very near future.  Linux
> assumes the vga registers are already initialized in vgacon.c (in
> drivers/video), and changes only a few register settings.  But (hopefully)
> for alpha mode (not graphics!), the register settings are standard for most
> vga cards and the init can be done in linuxbios without a vga bios.  If it
> turns out that this not true for most modern VGA cards (I am not sure right
> now), and there are extended register settings for alpha mode, then it will
> likely be too difficult to setup alpha mode from linux bios.  Extended
> registers are poorly documented and can be a mess.
> 
> Maybe someone knows if alphanumeric mode setup is via the standard VGA
> register set on most modern VGA cards.
> 

I am afraid your are wrong. For modern VGA cards, there is actually no
alphanumeric mode. These alphanumeric mode were simulated by BIOS or 
drivers. The worst thing, if you have no documents about these extended
registers, you have no way to drive the clock gen for Dot clock, Hsync, 
Vsync.

Ollie

> -Steve





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