Date: Mon, 27 Jan 1997 17:36:10 -0600 (MDT)
From: Roger Ivie <IVIE AT cc DOT usu DOT edu>
Subject: [opendos] Re: OpenDOS to be released next week!
To: OPENDOS AT MAIL DOT TACOMA DOT NET
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Oh boy! I get to climb on the soapbox!

Mike Harris wrote:
>On Wed, 22 Jan 1997, Chip Turner wrote:
>> For instance, the 640k barrier.  Technical details omitted, suffice it to
>> say that the original 8088/8086 processors could only address 1 meg total.
>> This had to include memory for programs but also ROM for the BIOS and video
>> card (not much else; this was before there were many different expansion
>> boards).  This had to be placed somewhere in the 1meg, 

Not necessarily. SOP in the CP/M world is to switch the boot ROM out once
the OS is up. Machines such as the Kaypro line also switched out the (ugh!)
memory mapped video. Of cousre, we also tend to like serial consoles so we
don't have to worry about memory mapped video in the first place...

> Agreed.  MS didn't MAKE the INTEL architecture, however the OS could
> have been coded more portably so that programs could have room to
> breathe in future architectures.  

MS-DOS used to be highly portable to non-PC machines. The DEC Rainbow, for
instance, runs MS-DOS just fine despite being a non-PC clone. It also
allows up to 896K of user memory instead of the piddly 640K allowed by the
PC architecture. Of course, this is still an Intel-based machine...

Of course, one of the things I'll be really interested in looking at when the
sources are available is the possibility of running OpenDOS on non-PC clone
hardware (still Intel-based of course, just things like 386EX embedded 
systems, etc).

>> Yeah, I agree with all you've said here, but I still think that they
>> could have done a much better job and broken the OS barriers earlier.
>> The 386 was out in '85 or so and it is just NOW that we're really
>> getting to actually USE the damned thing!!!  I'm talking about
>> Linux/OS2/NT/and DOS extenders.  These things could all have easily
>> been around 10 years earlier.

Lest anyone forget, DR had MP/M-86, Concurrent CP/M-86, and DR MultiUser
DOS running for many years before Novell gave up on DOS. These things 
allow better use of even 8086 machines than MS-DOS ever allowed. It'll be
interesting to see how much Caldera can find in the stuff they bought
from Novell.

Roger Ivie
ivie AT cc DOT usu DOT edu