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Re: [colorforth] Reverse engineering the BIOS

On Sat, 6 Mar 2004, Mark Slicker wrote:

> On Thu, 4 Mar 2004, Albert van der Horst wrote:
>
> > Dear all,
> > This is a side trail. We want to analyse the BIOS in order
> > to extract information about interfacing colorforth to the hardware.
> > Whoever wants to be involved, will have to contact me directly,
> > because I will not burden the colorforth mailing list after this
> > message (until practical successes.)
>
> I am just curious what you expect to find. The two sources of
> incompatibility of colorForth are the floppy and video. The video is

Exactly that.

> hopeless unless you are prepared to write a driver for the card. For the
  ^^^^^^^^
I don't think so. From the perspective of a Forther who is used to write
his own, it may look so. From my perspective (with maybe more experience
in reverse engineering than in Forth) it isn't.

> floppy perhaps a look at the bios will provide insight. However in
                                                  ^^^^^^
A reverse engineer is not necessarily after insight about how it works.
Insight about how you can call it is sufficient.

> this case you are not interested in whole bios, just the part that deals
> with floppy. This is just something to consider, you may find the
> complexity of the bios undermines a complete understanding.

I am pretty sure I must set my dogs (the disassembler) after the whole
BIOS. You are right that it helps that I want to deal with one or two
tiny aspects. If not the complexity, then the amount of code in the BIOS
makes complete understanding impossible. But that is not needed to
attain our very limited goals. Interestingly a 2 Mbyte BIOS doesn't
scare me dogs, no more than a 32 kbyte BIOS. They'll chew a little longer.

Look at it this way. Why would you love to have a nice 3000 page
description of the BIOS? To look in the index and see what chapters
you can skip...

Anyway, I'm determined to go on, and anyone interested can come
on board.

> Mark

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.
albert@xxxxxxxxxxxxxxxxxx     http://home.hccnet.nl/a.w.m.van.der.horst

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