5 Oct
2007
5 Oct
'07
4:28 a.m.
From: "Michael Kerpan"
<madcrow.maxwell(a)gmail.com>
Date: Thu, 4 Oct 2007 14:44:27 -0400
Awesome work. I notice that you require at least a 486 to run this
though. Is there any technical reason, or could this be moved to a 386
by means of a simple recompile? Also, how 32-bit IS the port? Would it
be hard to build a 286 version or even 8086/8088 version to give a
real OS to the old XT/AT in the basement?
8086 lacks the required protected mode. don't remember how xenix over
came this problem when it was first released. no one even has to think
about this problem today
5 Oct
5 Oct
4:44 a.m.
New subject: New V7 port available
tuhs(a)cuzuco.com scripsit:
8086 lacks the required protected mode. don't
remember how xenix over
came this problem when it was first released. no one even has to think
about this problem today
Coherent also ran on the x86, and is available for download
(its copyright status is uncertain); chase links from
http://en.wikipedia.org/wiki/Coherent_(operating_system) .
--
We pledge allegiance to the penguin John Cowan
and to the intellectual property regime cowan(a)ccil.org
for which he stands, one world under http://www.ccil.org/~cowan
Linux, with free music and open source
software for all. --Julian Dibbell on Brazil, edited
5:11 a.m.
New subject: New V7 port available
In message: <20071005044448.GK27520(a)mercury.ccil.org>
John Cowan <cowan(a)ccil.org> writes:
: tuhs(a)cuzuco.com scripsit:
:
: > 8086 lacks the required protected mode. don't remember how xenix over
: > came this problem when it was first released. no one even has to think
: > about this problem today
:
: Coherent also ran on the x86, and is available for download
: (its copyright status is uncertain); chase links from
: http://en.wikipedia.org/wiki/Coherent_(operating_system) .
Coherent was a v6 port. There was a Dec Rainbow port as well, but
nobody seems to have a copy of that anymore. The only copies I've
been able to find are for either the 286 or 8086. The 286 version was
a v7 port, iirc.
Warner
6:11 a.m.
New subject: New V7 port available
M. Warner Losh wrote:
Coherent was a v6 port. There was a Dec Rainbow port
as well, but
nobody seems to have a copy of that anymore. The only copies I've
been able to find are for either the 286 or 8086. The 286 version was
a v7 port, iirc.
Coherent wasn't a port of Research Unix. It was written from scratch.
5:10 a.m.
New subject: New V7 port available
tuhs(a)cuzuco.com wrote:
8086 lacks the required protected mode. don't
remember how xenix over
came this problem when it was first released. no one even has to think
about this problem today
Xenix for the 8086 only supported "small model" user programs of up to
64k text + 64k data
and used the segment registers to point to the appropriate text and data
segments in physical
memory. User programs were not supposed to ever look at or change the
contents of their
segment registers - if they did then chaos was likely to ensue.
And, of course, there was no protection so a rogue process could access
all of physical
memory including the memory used by the kernel.
It's quite amazing that it worked as well as it did.
md
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4 comments
5 participants
participants (5)
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Andrew Warkentin -
John Cowan -
M. Warner Losh -
Michael Davidson -
tuhs＠cuzuco.com