[OpenBIOS] Development environment, testing, sample code...

[David Woodhouse]

I suggest that we use dev86 for our development environment. It includes a C
compiler capable of generating both real mode and protected mode code, along
with libraries for each and binutils, amongst other toys.

Its output formats include Linux OMAGIC, ELKS, DOS .COM (small or tiny model),
and - this is the important one - standalone code. It has libraries suitable
for each target.

It can be found at http://www.linux.org.uk/ELKS-Home/dev14.html

I've also been investigating testing possibilities - Dosemu and Bochs seem to
be the main contenders. Of these, Bochs does a more complete emulation of the
hardware. So much so, in fact, that it can even run Win95 in an X window, 
albeit slowly.

In general, the BIOS in Dosemu does callbacks into the Dosemu code, while the
Bochs BIOS code actually tries to manipulate the hardware, letting the Bochs
host code trap and emulate the actual IO accesses. This means that we'd be
better off testing our BIOS code under Bochs.

Bochs is available at http://world.std.com/~bochs

Remember, though:
> The general registration fee for BOCHS is $25 per workstation, PC, or
> X-terminal, and should be paid by check in U.S. funds to:
> Kevin Lawton
> Bochs Software Company
> 528 Lexington St.
> Waltham, MA 02154

Both Bochs and Dosemu have BIOS code which we can learn from, but can't copy. 
Bochs is commercial, and Dosemu GPL. Neither can be used if we intend to 
release OpenBIOS under LGPL.

The interesting bits are:
    bochs-980124/bios/rombios.c 
and	dosemu-0.97.3/src/base/bios/bios.S

----                              ----                              ----
David Woodhouse, Robinson College, CB3 9AN, England.   ([phone]
    [e-mail]        http://dwmw2.robinson.cam.ac.uk
        finger [e-mail] for PGP key.

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