copy extended memory.

Adam Sulmicki adam at
Sun Oct 27 19:55:02 CET 2002

> This is such a bitch.


>  I simply could not get this to work

you can find nice example how to use it in linux sources
(some file in linux/arch/i386/boot, head.S IIRC)

> Here's what RB says anyway:
> [snip]
> It should all be pretty straight forward.  The 16 bytes at 00h and the 18
> bytes at 1Eh are probably best used by BIOS to set up it's own segments for
> usage during the copy.

yeah, but I hoped for more authoritative answer than DB.

For example the description in Phoenix's user manual is just plain wrong
:/ It will describe an single GDT entry, but it will not say how many
entries and what is meaning of each entry.

> And don't forget the 32-bit opcodes when in pmode.

Isn't that dependent on D/B flag in appropriate GDT entry?  So if I set 16
b it D/B flag in the CS entry, I still should be able to use 16 bit code,
even if in 32 bit mode.

Adam	The Supreme Headquarters of the 32 bit registers

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