Z-80 Unix?

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Chris Rende

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Sep 15, 1988, 9:26:49 AM9/15/88
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In his book "The Unix Operating System" Kaare Christian mentions that Unix
exists for the Z-80. This was a big suprise to me. I didn't know that Unix ran
on any 8 bit CPU's.

Does anyone know anything about Unix running on a Z-80?

car.
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Stephen J. Friedl

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Sep 17, 1988, 10:09:12 PM9/17/88
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In article <2...@pte.UUCP>, c...@pte.UUCP (Chris Rende) writes:
> In his book "The Unix Operating System" Kaare Christian mentions that Unix
> exists for the Z-80. This was a big suprise to me. I didn't know that Unix ran
> on any 8 bit CPU's.
>
> Does anyone know anything about Unix running on a Z-80?

My memory is a little fuzzy, but Morrow Designs [R.I.P.] had a
banked Z80 box running a *v6* UNIX that I think was called `Micronix'.
It must have been 1981-83, and they used v6 because they could
make it fit in the limited memory. I've no clue on performance
or anything like that.

Morrow was a God in the Z80 world but he stayed in it too long when
the IBM PC came out :-(.
--
Steve Friedl V-Systems, Inc. +1 714 545 6442 3B2-kind-of-guy
fri...@vsi.com {backbones}!vsi.com!friedl attmail!vsi!friedl
------------Nancy Reagan on conductance: "Just say mho"------------

Peter Zadrozny

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Sep 19, 1988, 10:05:32 AM9/19/88
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In article <2...@pte.UUCP>, c...@pte.UUCP (Chris Rende) writes:
> Does anyone know anything about Unix running on a Z-80?

Years ago I worked with a series of Cromemco computers,
they where Z-80 S-100 based machines and ran Cromix as
their operating system. Cromix was a pretty good implementation
of Unix even with the limitations imposed by the CPU.
The requirements were one 64K bank for the OS and
one 64K bank for every user (process). The multi-tasking
multi-processing was achieved by bank switching. It was interesting
to be able to run WordStar and dBase II in a "Unix" environment
(since it had a CP/M emulator which resided on the top 3K of the
corresponding bank). More interesting was experiencing the
power a 4MHz Z-80 handling with little visible effect one
secretary hacking the keyboard with WordStar, one clerk
running a dBase II application, and myself compiling little
C monsters. They also had a very good Basic compiler as well
as a Basic based OS (a la RSTS-11).

I do believe that Cromemco is still in business (I saw somebody
in the SF Usenix sporting a badge with their name). They are based
in Mountain View. BTW, most of the computerized TV weather reports
use Cromemco Z-80 machines.

-----------------------------------------------------------------
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Mark Davidson

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Sep 19, 1988, 11:14:05 AM9/19/88
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Years ago, the C Users Group talked about a Z-80 Unix-like operating system
in one of their newsletters. (I don't know about now, but back then, you got
a copy of all the back-issues when you joined; that's where I saw it)
Unfortunately, I don't think it was ever released, as the author of the
system was killed in a swimming or boating accident (I think).
--
In real life: Mark E. Davidson uflorida!novavax!proxftl!markd
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Stephen J. Friedl

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Sep 19, 1988, 9:45:52 PM9/19/88
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In article <7...@proxftl.UUCP>, ma...@proxftl.UUCP (Mark Davidson) writes:
>
> Years ago, the C Users Group talked about a Z-80 Unix-like operating system
> in one of their newsletters. (I don't know about now, but back then, you got
> a copy of all the back-issues when you joined; that's where I saw it)
> Unfortunately, I don't think it was ever released, as the author of the
> system was killed in a swimming or boating accident (I think).

I am digging *way* back here, but I think this was the Mark
operating system. I think the name was Ed Zeimba [??], a friend
of Leor Zolman (creator of BDS C). I don't think it was ever
finished :-(.

Whatever happened to Leor?

Steve

Robert Lee Bailey

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Sep 19, 1988, 10:17:47 PM9/19/88
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In article <2...@pte.UUCP> c...@pte.UUCP (Chris Rende) writes:
>In his book "The Unix Operating System" Kaare Christian mentions that Unix
>exists for the Z-80. This was a big suprise to me. I didn't know that Unix ran
>on any 8 bit CPU's.
>
>Does anyone know anything about Unix running on a Z-80?
>
I, too, would be interested in Unix on a Z-80! (In my dreams, right?)
~r
Bob Bailey

Andrew Klossner

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Sep 20, 1988, 12:29:33 PM9/20/88
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[]

"Years ago, the C Users Group talked about a Z-80 Unix-like
operating system in one of their newsletters. (I don't know
about now, but back then, you got a copy of all the back-issues
when you joined; that's where I saw it) Unfortunately, I don't
think it was ever released, as the author of the system was
killed in a swimming or boating accident (I think)."

This was the MARC system (I think that's the name ... elapsed time
isn't good for brain cells). Scuttlebutt at the time had it that, upon
the fellow's death, one of his acquaintances, a Los Angeles area
consultant, swooped in on the grieving widow and talked her into
selling him exclusive rights to the work in progress. He then spent
years getting it in shape on a part-time basis, issuing periodic,
tantalizing "it's almost done" notes to the net, until an un-backed-up
hard disk crashed and all was lost.

(The "swooping" part is single-source rumor. The rest is confirmed.)

-=- Andrew Klossner (decvax!tektronix!tekecs!andrew) [UUCP]
(andrew%tekecs....@relay.cs.net) [ARPA]

Doug Braun ~

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Sep 20, 1988, 12:44:15 PM9/20/88
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In article <2...@pte.UUCP> c...@pte.UUCP (Chris Rende) writes:
>In his book "The Unix Operating System" Kaare Christian mentions that Unix
>exists for the Z-80. This was a big suprise to me. I didn't know that Unix ran
>on any 8 bit CPU's.

I wrote one a couple of years ago. It is a totally from-scratch implementation
of the Unix kernel for a 64K CP/M machine. It runs just fine on my machine,
being able to support the 7th edition shell with no problems. I would be
glad to mail the source code or post it to the net.

It works like this: The kernel is in the top 32K, and a process exists
in the bottom 32K. Process switching happens by total swapping. This
arrangement is like the "Mini-Unix" that Bell Labs put out for the smallest
PDP-11's a while back.

Virtually all of the 7th Edition system calls, and most of its functionality
are implemented. Here are the restrictions that I remember offhand:

The debugger system call does not exist (but profiling does exist).
The TTY driver is bare-bones and supports only one TTY.
Inode numbers are 16 bits, so there can be only 32 Meg partitions.
The seek system call uses the old 6th Edition arguments (no 32 bit arguments)
The time and stime system calls use the MS-DOS format for times.
Because of the total swapping, disk I/O is synchronous. There is no point
running another process while one waits for disk I/O, since you would
have to swap it in. The locks and semaphores needed to implement this are
also not present.

On the bright side, everything else seems to work fine. Execve, fork, wait,
etc., all work correctly. The number of processes is limited only by table
sizes (and your patience). Links, pipes, random file access, owner, and
group permissions work correctly. The 4.2BSD stdio library was ported
to the system.

This was written to run on my custom-built hardware. There is no hardware
memory management, just custom disk, tape (9-track!!), and serial I/O
hardware. Of course, the system supports major and minor devices and
character and block device tables, so adding in new drivers is not too
hard.

The kernel was completely written by me, but unfortunately I cannot legally
distribute the shell, ed, cpp, tar, and 15 or so other utilities I ported
to this system. It was compiled by the Q/C compiler (under CP/M) along
with a ported version of cpp. Also, I was never able to get the C
compiler to fit in 32K, but cpp, a patched version of the M80 assembler,
and a linker written by me all run under the system. I also wrote
some utilities such as fsck and ps that are very kernel-dependent.
Most of the Minix programs would probably port to this system, though.

If anybody would like to look at this stuff, let me know, and I will
dig out the disks and figure out how to upload them.

Doug Braun Intel Corp CAD
408 765-4279

/ decwrl \
| hplabs |
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| amd |
\ qantel /

Rex A. Buddenberg

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Sep 21, 1988, 8:46:54 PM9/21/88
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Doug,

This looks really interesting.

1. Suggest you consider uploading to Simtel20 or similar where
we can get at it. This is assuming, as you implied, that your
work is for public domain.

2. What are implications for the follow-on Z-80 derivative chips
like HD64180 and Z-280? How portable are we here? If you can make
things work in a 64k RAM space, life ought to get easier if you can
lay hands on more RAM... Somehow sounds like an awkward fit though
until you get hardware memory management to take a lot of the load off
your code...muse,muse,muse.

Rex Buddenberg

Mark Zenier

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Sep 22, 1988, 5:09:13 PM9/22/88
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In article <2...@pte.UUCP>, c...@pte.UUCP (Chris Rende) writes:
> In his book "The Unix Operating System" Kaare Christian mentions that Unix
> exists for the Z-80. This was a big suprise to me. I didn't know that Unix ran
> on any 8 bit CPU's.
>
> Does anyone know anything about Unix running on a Z-80?

Whitesmiths may have done IDRIS for the Z80.

Charles Lambert

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Sep 23, 1988, 10:32:14 AM9/23/88
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In article <8...@vsi.UUCP> fri...@vsi.UUCP (Stephen J. Friedl) writes:
>
>Morrow was a God in the Z80 world but he stayed in it too long when
>the IBM PC came out :-(.

He should've emigrated. Alan Sugar is still wringing cash out of the little
monster in Europe :-)

----------
Charlie

William E. Davidsen Jr

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Sep 23, 1988, 2:36:00 PM9/23/88
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In article <7...@tetra.NOSC.MIL> bud...@tetra.nosc.mil.UUCP (Rex A. Buddenberg) writes:

| 2. What are implications for the follow-on Z-80 derivative chips
| like HD64180 and Z-280? How portable are we here? If you can make
| things work in a 64k RAM space, life ought to get easier if you can
| lay hands on more RAM... Somehow sounds like an awkward fit though
| until you get hardware memory management to take a lot of the load off
| your code...muse,muse,muse.

I hacked CP/M to live in an alternate memory bank (actually I ran it
in the 2nd bank and had a faker in the main memory). Using that
technique you could get more memory for UNIX and possibly run a lot more
of it. That would allow you to have multiple processes, too, since there
would be virtually no swap overhead. I don't know about i/o, I can't
think of any *cheap* way to do it into an unselected bank.
--
bill davidsen (we...@ge-crd.arpa)
{uunet | philabs}!steinmetz!crdos1!davidsen
"Stupidity, like virtue, is its own reward" -me

Rusty

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Sep 23, 1988, 3:53:02 PM9/23/88
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In article <29...@mipos3.intel.com> dbr...@cadavr.UUCP (Doug Braun ~) writes:
....

>I wrote one a couple of years ago. It is a totally from-scratch implementation
>of the Unix kernel for a 64K CP/M machine. It runs just fine on my machine,
>being able to support the 7th edition shell with no problems. I would be
>glad to mail the source code or post it to the net.
>
POST! POST! well, email if not enough people agree, but I seriously doubt
that will happen.

>The kernel was completely written by me, but unfortunately I cannot legally

>distribute...

Maybe we can figure a way around this?

-----
Rusty Carruth UUCP: {uunet,boulder}!cadnetix!rusty DOMAIN: ru...@cadnetix.com
Cadnetix Corp. (303) 444-8075x296 \ 5775 Flatiron Pkwy. \ Boulder, Co 80301
Radio: N7IKQ 'home': P.O.B. 461 \ Lafayette, CO 80026

John Antypas

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Sep 24, 1988, 3:20:48 AM9/24/88
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>In article <2...@pte.UUCP>, c...@pte.UUCP (Chris Rende) writes:
>> In his book "The Unix Operating System" Kaare Christian mentions that Unix
>> exists for Z-80. This was a big suprise to me. I didn't know that Unix ran

>> on any 8 bit CPU's.
>>
>> Does anyone know anything about Unix running on a Z-80?
>
>Whitesmiths may have done IDRIS for the Z80.

Indeed they did, but I wouldn't exactly call it Unix. Our labs use Idris
because we must, and the C alone is semi-Unix-like if you look at it
just the right way. They rewrote litterally 90% of the libraries. Truly
non-portable code!

Stephen J. Friedl

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Sep 24, 1988, 1:30:27 PM9/24/88
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In article <4...@ucrmath.UUCP>, jant...@ucrmath.UUCP (John Antypas) writes:
> >
> >Whitesmiths may have done IDRIS for the Z80.
>
> Indeed they did, but I wouldn't exactly call it Unix. Our labs use Idris
> because we must, and the C alone is semi-Unix-like if you look at it
> just the right way. They rewrote literally 90% of the libraries. Truly
> non-portable code!

In the early days, Whitesmiths felt they were In Charge of C
programming. Above, `rewrote 90% of the libraries' means that
the usage and function names were different as well. For example:

putfmt("The number is %i\n", i);

replaced your good old printf. After a time, they released a
compatible library, but it was likely due to outrage. I have
never in the meantime seen such a blatant example of gratuitous
incompatibility. What is surprising is that this came from
the man who cowrite _Elements of Programming Style_, P.J.
Plauger. Sad.

My memory is a bit dated on the details, corrections welcome.

Steve

--
Steve Friedl V-Systems, Inc. +1 714 545 6442 3B2-kind-of-guy
fri...@vsi.com {backbones}!vsi.com!friedl attmail!vsi!friedl

------[I'm on vacation in Ohio from 26-Sep to 10-Oct 1988]----------

Andrew Klossner

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Sep 26, 1988, 11:09:11 AM9/26/88
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[]

"I have never in the meantime seen such a blatant example of
gratuitous incompatibility. What is surprising is that this
came from the man who cowrite _Elements of Programming Style_,
P.J. Plauger."

This discussion has overlooked the motivation of Unix incompatibility
in Idris. Plauger and associates were scared that AT&T lawyers would
shut them down under the trade secret laws because they had access to
Unix source code before they formed Whitesmiths. The "galloping
incompatibility" was an attempt to demonstrate that Idris was not a
Unix rip-off.

This was back in the days when the same company that sold Unix would
hassle you about adding an unregistered extension phone, and the
lowest-cost Unix license was $20,000 (no cheap binaries). I'd say
their concern was justified.

Tom Donohue

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Sep 28, 1988, 3:54:30 PM9/28/88
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In article <8...@vsi.UUCP>, fri...@vsi.UUCP (Stephen J. Friedl) writes:
> In the early days, Whitesmiths felt they were In Charge of C
> programming. Above, `rewrote 90% of the libraries' means that
> the usage and function names were different as well. For example:
>
> putfmt("The number is %i\n", i);
>
> replaced your good old printf. After a time, they released a
> compatible library, but it was likely due to outrage.


At the time (~1979), I beleive Whitesmiths was afraid of incurring
the wrath of AT&T. Copyrights and such. Perhaps they were overly
cautious, or perhaps it was a valid concern. I don't know where
I heard this, but it wasn't from Whitesmiths, so take it with a grain
of salt.
--
-- tom ...!{rutgers,uunet}!cbmvax!hutch!tom

Dennis S. Breckenridge

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Sep 28, 1988, 9:53:26 PM9/28/88
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In article <29...@mipos3.intel.com>, dbr...@cadavr.intel.com (Doug Braun ~) writes:
> In article <2...@pte.UUCP> c...@pte.UUCP (Chris Rende) writes:
> >In his book "The Unix Operating System" Kaare Christian mentions that Unix
> >exists for the Z-80. This was a big suprise to me. I didn't know that Unix ran
> >on any 8 bit CPU's.
>
> If anybody would like to look at this stuff, let me know, and I will
> dig out the disks and figure out how to upload them.
>
> Doug Braun Intel Corp CAD
> 408 765-4279
>
> / decwrl \
> | hplabs |
> -| oliveb |- !intelca!mipos3!cadev4!dbraun
> | amd |
> \ qantel /

I tried to send you mail directly but it bounced from mordor - joyce.

Subject: UNIX Z80

Hi Doug, I seen you posting for the source for z80 UNIX (tm) and I am very
interested in getting a copy. I should mention that I work for AT&T Canada
I am in the National Technical Support area and can be reached at ...!attcan!
dennis or here on my 6386 at home.
I have several CP/M systems lying around here and it would be great fun to
try and get UNIX running on at least one of them. I do not have any version
7 source.

Thanks in advance

--
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waste!" 206 Poyntz Ave
North York, Ontario M2N1J6
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