copy extended memory.
Eric W. Biederman
ebiederman at lnxi.com
Sat Oct 26 11:02:00 CEST 2002
Adam Sulmicki <adam at cfar.umd.edu> writes:
> can anyone point me to an documenation on bios's
> interrupt 15, ah=87. It is 'copy extended memory'.
> I suspect the implementation I have is wrong, and
> thus stops me from adding support for legacy
> applications under LinuxBIOS.
> Going over phoenix manual and Ralf Browns's
> interrupt list, I know that
> CX = counter
> ES:SI = pointer to GDT
> what is not clear to me is what does determine source and destination
> of the copy. Would it just copy between first and second segment
> (if so why it is not documented).
I have in my documentation the following addtional information.
CX is a count of works (2 byte quantities) With the max being
And the format of the GDT is:
source GDT entry
target GDT entry
This code works for a 286 so it has a 16MB limit. And segments
are limted to 64K, if my memory serves me correctly.
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