On Saturday 29 July 2006 03:09, Timothy Miller wrote:
> On 7/28/06, James Richard Tyrer <[EMAIL PROTECTED]> wrote:
> > Also, I still don't know how my MotherBoard's BIOS displays that
> > Energy-Star logo, but it obviously isn't using TTY mode.
>
> I do.  I had to write a VGA BIOS once.
<hack involving character glyph table>

ISTR experimenting with this back in the days of Turbo Pascal and inline 
asm direct VGA programming. Many of the techniques described in the 
tutorials of the day came from the demoscene. I always suspected that 
this hack could be used to display that logo, and it's interesting to 
see that it really did make it into the mainstream this way.

> Another thing I recall is that, at least for this MoBo, it started up
> first in the EGA mode where the physical resolution is 640x350 (or
> 720x350), and the character cells are 8x14.  Then it switches modes
> to the VGA [EMAIL PROTECTED] (or 720x400), with 8x16 (or 9x16) cells.
>
> I was never sure where the 9th pixel came from.

IIRC, the eighth column was repeated. Normal letters and symbols have 
that final column empty, so there's just one pixel extra spacing. The 
only characters using it are the special characters used to draw 
frames, and repeating the last column makes them connect nicely.

Lourens

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