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RE: [colorforth] Reverse engineering the BIOS (2)


On Sat, 24 Apr 2004 howerd.oakford@xxxxxxxxxxxx wrote:

> Hi Albert,
>
> An obvious question - how do you decide on the name and address of the
> labels based only on the BIOS code?

Artificial and natural intelligence, cheating, Ralphs BIOS information,
google and everything else that serves the goal.

> Are the sections of code always bounded by call-ret pairs?

That is actually a good name SECTION !

The answer is no, even if I generalise your question to "points of
unconditional transfer to and from in pairs." Sections of code, byte,
strings, words are reverse information and ultimately under user
control. The bag SECTION will essentially be a number of labels,
starting out as DON'T-KNOW sections.
They can be proposed by a crawler that starts from the reset vector,
or from any vectors in the interrupt table that point into ROM.
Unfortunately, by the time DOS has started, many or all of those
interrupts are compromised (revectored by DOS to suit their purpose.)

I'm not sure yet whether I want them in begin-end pairs, or with
automatic ending at the next section.

> Howerd
Groetjes Albert
>

<SNIP>
You should have snipped the code at least.

Groetjes Albert

P.S. I hope not to offend people by posting ciforth code.
It is all I got for now.

Albert van der Horst,Oranjestr 8,3511 RA UTRECHT,THE NETHERLANDS
        One man-hour to invent,
                One man-week to implement,
                        One lawyer-year to patent.
albertt@xxxxxxxxxxxxxxxxxx http://home.hccnet.nl/a.w.m.van.der.horst

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