From: linstee@dutecaj.et.tudelft.nl (Erik van Linstee)
Subject: BIOS arguments (Was: is Windows 3.1 ....)
Organization: Delft University of Technology, Dept. of Electrical Engineering
Date: Mon, 23 Nov 1992 13:44:16 GMT


Joe writes:

>In article <1992Nov20.104838.28137@donau.et.tudelft.nl> linstee@dutecaj.et.tudelft.nl (Erik van Linstee) writes:
>>To Joe:
>>
>>You keep failing to grasp that the bootstrap loader is NOT part of the
>>BIOS, it is a totally seperate function, ONLY in the same black little
>>thingy. As long as you can't see that, your arguments about the BIOS
>>being part of DOS lack credibility.
>>
>>Good luck
>>Erik
>>

>The bootstrap loader uses the same "BIOS" low-level disk routines that
>INT 13 uses (check the BIOS listing in the AT Technical reference manual).

Think of this. You have to write a bootstrap loader for some machine.
Major part of it is to write the code to access the bootstrap device.
Now, you're writing a BIOS. Part of it is to write an interface
to a storage device.
If you're doing booth you obviously do not choos to write this code
twice only because they're for two different things. Obviously you
use the code you already wrote for the BIOS to access the bootstrap
device from the bootstrap loader. This is only the sensible thing to
do. This doesn't connect the BIOS to the bootstrap loader or vice
versa. They remain separate functions.

>So, the argument really isn't whether the bootstrap loader is part of the
>BIOS (because at least *part* of it is)... but whether or not the mere

Here, you use the same argument you use to say the BIOS is part
of DOS, because one uses the other. This is exactly what we are 
argueing about.

>use of the BIOS during bootup by an operating system constitutes that
>(at least in small part) the BIOS is part of the operating system.  After
>suitable reflection, I think that it is not (hence, the BIOS is not part of
>OS/2 unless OS/2 depends on the BIOS for other functions, such as a DOS 
>window).

>But, the BIOS routines are well integrated into DOS (At least DOS on *my* 
>PC).  And DOS programmers and DOS programming books have accepted that
>the BIOS INT functions are a valid API for DOS programs--so much so that
>the BIOS can be considered *part* of DOS (by the OS definition by
>D. Comer in _Operating System Design, a XINU approach_), if not de jure
>then at the very least de facto.

Now this is a totally different thing. The BIOS routines *are* well
integrated into DOS and many programmers use the BIOS routines
expecting them to be their because they are programming for DOS.
You spoil it though by saying it can be considered part of DOS. You
most likely mean, it is so common to DOS machines that anyone who
hears about DOS envisions a machine having a BIOS. I think you
mean to say, the BIOS is so common to DOS machines that any
programmer writing for DOS uses BIOS routines to perform certain
tasks because it is very very likely that the target machine has
a BIOS to perform those functions.


>TO recap this thread, the arguments therefore go like this:

>    Windows is not an operating system.
>    Sure it is, it performs all operating system functions in the
>      textbook definition (cited _System Software_ by L. Beck)
>    But it's built on top of DOS.
>    So what?  DOS is simply another layer in the Windows operating system
>       design (cited Beck, and, may I add, D. Comer  in _Operating
>       System Design_ *insists* on a layered approach in operating system
>       design).
>    But even DOS is not an operating system.
>    So people have been using a computer without an operating system for over
>       15 years?
>    But an OS should handle all hardware related interfaces.  It doesn't
>       even do graphics.
>    An OS doesn't have to handle all hardware (examples of specialized
>       hardware that no OS handles out-of-the-box).  Besides the graphics
>       routines are handled adequately (cough,cough) by the BIOS.  In
>       this sense, the BIOS can be considered part of DOS (cites reference
>       from D. Comer).  Hints that the BIOS may be part of OS/2 because
>       (a) it uses the BIOS to boot (and may use the BIOS for DOS windows),
>       but the minimal use of the BIOS routines in this respect makes such
>       classification a grey area.
>    But the BIOS is part of the PC architecture.
>    Anything that is built on is an "architecture." (definition of
>       architecture from Webster's Dictionary).  If one's PC development
Architecture:

'The architecture of a computer system can be defined as its functional
appearance to its immediate users.'    Amdahl, 1964

>       consists only of OS/2, then his PC Architecture includes OS/2.

For the developer the architecture IS OS/2. For the operating systems
designer the 80x86 with surrouding parts (including the BIOS) is the
architecture. For a user the architecture is DOS or OS/2 or whatever
is the current OS.

Quote:

The architecture can be regarded as the appearance of a system. The
term architecture was probably first applied to computers by Buchholz
(1962) in the description of the Strech computer. Yet is is obvious that,
viewed in the light of this definition, every mechanism in fact has an
architecture, so that the concept of 'system architecture' is much older.
When children are taught to tell the time, they are tought the
architecture of an analog clock. They learn that there are two
hands - the lang hand an, which indicates minutes, and the short hand,
which indicates hours - and that the position of both hands together
indicates te time. When they can distinguish this architecture from the
realization of the clock, they can use a wristwach as easily as a church
clock to see what time it is.

Computer architecture and design - A.J. van de Goor

By this quote you can tell why the BIOS is part of the IBM PC
architecture. It is there to always appear as an IBM PC to a user
even though the realisation of the hardware can be completely different.
As long as you go through the BIOS you have no problem, even if
the graphics adapter is at a totally different address and functions
completely differently from an MGO adapter.
DOS in its turn was written for the PC architecture so of course it
relies on the BIOS being there, just as you rely on there being hands
on an analog clock no matter if its made of wood, metal or sand, hangs
from the wall, floats in the air or bounces off the ceiling.
If you can agree on this than you must know it can't be part of DOS
since it can't be part of both. They *are* heavily connected though.

>       Besides, an operating system consists of a collection of software
>       that performs OS functions (D. Comer again)... as long as the BIOS
>       is considered *software* it could be considered part of the OS that uses
>       it.
>    But only the bootstrap loader is used by OS/2.  The loader is not part
>       of the BIOS, it's in the same ROM, but it is separate.  If you can't
>       get that through your head, your arguments about the BIOS being part
>       of DOS lack credibility.
>    The low level disk access routines are shared by the BIOS and loader 
>       (cites appendix H. BIOS listing of _AT Technical reference manual_).
>       Agrees that if OS/2 only uses the BIOS to boot, the BIOS is not part
>       of OS/2 (but questions whether or not OS/2 uses the BIOS for a DOS
>       window).

>As you can see, the thread has carried far from the original question: is
>Windows (plus DOS)  an operating system ?  But also note that only *one* 
>side of the argument is presenting references and definitions

First of all, I am my own reference. I showed that in another post
for this reason. I do not have to go around quoting other people,
as they do not have to go around qouting themselves, me or anyone
else of the same abilities.
Second, I have not seen any qoutes that say, or even imply that if
DOS uses the BIOS then the BIOS is part of DOS.



>>You keep failing to grasp that the bootstrap loader is NOT part of the
>>BIOS, it is a totally seperate function, ONLY in the same black little
>>thingy. As long as you can't see that, your arguments about the BIOS
>>being part of DOS lack credibility.

> 

>As long as people keep pulling definitions and concepts from a hat--without
>citing references, their entire argument lacks credibility.

See above. I'll give you some references though:

Computer architecture and design - A.J. van de Goor
Computer organization and architecture - W. Stallings
Delft University of Technology, faculty of electronics,
department of Computer Architecture And Digital Technique

-- 
Erik van Linstee   |   Delft University of Technology   |   I'll be back ... 
----
   We are god, 'cause only we can create the idea of his existence
   in our holy brains...  (Yello)
Newsgroups: comp.os.os2.advocacy