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.

For the text mode, there is a 32KiB space (or is it 64KiB?) divided
into 2KiB segments.  Some of those are 80x25 screens, and somewhere in
there is a character glyph table.  The location is standard for VGA,
so your MoBo's BIOS reprograms the character glyph table to have some
characters replaced with various pieces of the logo.  Then it puts up
the appropriate characters on the screen.  If you don't use the
character map, what you see instead is a jumble of IBM extended
graphics characters.

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.
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