Free BIOS (was Resources for DOS (was: DOS Compatable OS))
bob at jfcl.com
Fri Dec 16 10:23:49 CST 2005
Speaking of FreeDOS and DR DOS, is there also a "Free" BIOS?
Yes, I know the BIOS is hardware specific, but most PC compatible
platforms are the pretty much the same. Even if they aren't, it's nice to
have a starting point.
> -----Original Message-----
> From: cctalk-bounces at classiccmp.org
> [mailto:cctalk-bounces at classiccmp.org] On Behalf Of Hans Franke
> Sent: Friday, December 16, 2005 6:38 AM
> To: General Discussion: On-Topic and Off-Topic Posts
> Subject: Resources for DOS (was: DOS Compatable OS)
> Am 14 Dec 2005 16:11 meinte Gary Sparkes:
> > On 12/14/05 3:53 PM, "Sean 'Captain Napalm' Conner"
> <spc at conman.org>
> > wrote:
> > > It was thus said that the Great Gary Sparkes once stated:
> > >> I'm rather bored, so I thought I might try and hack together a
> > >> small project OS compatable with at least DOS 1.x or similar, is
> > >> there any decent resource for information on dos
> compatability and
> > >> how to achieve it, or is it left as a reverse
> engineering exercise
> > >> for 'the reader' ? :)
> > > How compatable? If you go by the published API for MS-DOS 1.x,
> > > then it should be pretty easy, but if by "compatable" you
> mean "run
> > > arbitrary MS-DOS programs, especially those from
> Microsoft" you may
> > > have your work cut out for you. You may want to check out
> > > http://www.freedos.org/.
> > I was thinking of going up compatability in versions, such as going
> > from 1.x to 2.x etc, mainly because, well, I'm very, very bored :)
> Well, that's like building two OSes, since 2 has been realy
> something ifferent, aimed at bridgeing the gap from XPM to Xenix.
> > And of course, it'd be IBM PC compatable stuff, not the odd machine
> > MS-DOS running thingies
> That's not the question. MS/PC Dos is a rather machine
> independent OS. as long as you a real mode x86 CPU, DOS
> itself is compatible across virtualy all machines. Dos uses
> for all its functionality BIOS calls and got no specialities
> to bind it to IBM-PC Hardware.
> Machine specific stuff was all in the BIOS - including lots
> of additional functionality for non-IBM machinery. So,
> straight DOS programms could be easy portet, if DOS was present.
> For incompatibilities there where two major resons:
> a) The Application did use Hardware and or BIOS specific functions,
> like writing directly to screen buffers, doing DMA or fiddling
> with the keyboard.
> b) The Application used inofficial/not public documentated MS-DOS
> calls, like $52 to get the DDA, the root of all things evil
> (and subsequent the memory chain, or the SFT (*1)).
> Most 'incompatible' application fall into cathegory a),
> except for lots of MS Programms, which belong to cat b). To
> my understanding this was what Sean ment with compatible
> beyond the published API.
> A real good book to stat of would be:
> Arne Sch"apers - DOS 5 f"ur Programmierer.
> I got no idea if there ever was an englisch edition, but it's
> eventualy the best analysis and documentation of DOS ever
> made. He covers not only DOS 2-5 but also DR-DOS and all
> similarities and differences. Think of it as a documented,
> debugged and extended version of
> Andrew Schulman (et.al) - Undocumented DOS
> Both books are from Addison-Wesley, so If you can't find
> Arnes, Undocumented DOS is a good start anyway. The other
> real helpful book would be
> The MS-DOS Enzyclopedia from MS-Press
> Good book, but of course only a compilation of the 'official'
> material. only about 20% cover the DOS API, the rest is
> somewhat like the mother of all DOS manuals. ~1500 pages in
> one book. If you need a DOS-manual, try to get this book. It
> even got a small entertaining history secttion. Originaly it
> was HUGE a hard cover book for a unpayable price (I remember
> 500+ Mark).
> Another very important book might be
> Gunter Born - Dateiformate - Die Referenz
> Again, German, and I don't know about a similar English book.
> It lists everything from Lotus to Word, from Autocad to GEM.
> Quite helpful - did I mention that I love to have information
> as paper in front of me?
> Oh, and last but not least, keep Ralf Browns IntList at hand
> when starting the project, Sos is more than just INT 21.
> *1 - I'm not completely shure it $52 was already present in DOS 1.0,
> but it seams to make sense, especialy since funcions like $50/51
> (GET/SET PSP) or $53 (TRANSLATE BPB) are in the same range and
> should have been already present in 1.0 to my understanding.
> Fits also with the idea of starting 'internal' functions at
> such a number (80 decimal)
> VCF Europa 7.0 am 29/30.April und 01.Mai 2006 in Muenchen
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