RTL for Z8000 series CPU?

Chuck F.,

> At that time engineers had a lot more sense than they seem to
> today, and wouldn't consider designing in a sole-source part.  Thus
> the license was a business necessity.

I wish we could bring the same business necessity around again...
Engineers today have no options left - things get monopolised
faster than developed. It is a social rather than a technical problem,
not necessarily solvable in our lifetimes.
 Not that I disagree with you that engineers had more sense back then
:-),
to me a person using tools which do things he/she does not understand
in detail is a machine operator, not an engineer...

Dimiter

------------------------------------------------------
Dimiter Popoff               Transgalactic Instruments

http://www.tgi-sci.com
------------------------------------------------------

ajcrm125 wrote:
> Hey guys, does anyone know where I can get VHDL/Verilog source for the
> Z8001/Z8002 processor?
> Thanks for any info!
>
> -Adam
> ajcrm125@gmail.com

So why exactly would you want such a design? Do you have Z8000 binary
code you must run?

As noted below other IP shops have functionally reversed engineered it.
I recall one aerospace company had to run old code with timing
precision and paid for the Z8000 design to be redone. A functional
clone could give good guarantee that machine codes would run in same
time clock for clock. The Z8000 was complicated enough but was still a
fully predictable design as far as external events were concerned ie no
caches.

As it happens I also reverse engineered some of the Z8000 blocks around
79 and still have paper docs for the datapath, but that wouldn't get
you very far today. Also a good collection of comp arch books before
the H &P bandwagon took over, would often describe the
microarchitectures in some detail of most all mid 70s and earlier
designs.

If you don't need cycle accuracy, why not write a ISA translator and
retarget to Arm, x86, whatever. With the speed advantage you would get
a few orders of improvement. Thats probably already been done too!

transputer guy

Peter Alfke wrote:
> Let me clarify:
> Intel developed and designed the 4004, then 8008, which evolved into
> the 8080. Then there ws the race to 16 bits: Intel 8086, Motorola
> 68000, and Zilog Z8000.
> Intel also made an economy-version of the 8086, called 8088 (8-bit bus
> insted of 16-bit), and IBM picked this intel 8088 for their PC. IBM was
> not in the commodity microprocessor business in those days, and IBM
> never manufactured 8086-like chips.

They did!

There were several 386 and 486 level chips designed and manufactured by 
IBM based on the agreement with Intel. IBM 386SLC, 486SLC and 486BL 
series are the examples. The chips carried Intel's and IBM's copyrights 
and incorporated a reasonable amount of cache. I still have some PS/2 
computers with IBM 486SLC2 and SLC3 CPUs inside.

Then IBM served several x86 companies as chip foundry. They did it at 
least for NexGen, Cyrix and  AMD.

ajcrm125 schrieb:
> How would I be violating anything if I made a Z8000 equivalent design
> in Verilog/VHDL?  I mean, if they had source for it, and I tweaked it
> slightly and called it my own, I can see where that crosses the line.
> But reverse engineering a design from its databook and creating a clone
> isn't copyright infringement from what I understand.
> What do you think?

ISAs are not protected under copyright law. (The ISA documents and the
CPU design are, but not the ISA)

The real pitfall are patents. As Peter noted all original pantents
should be invalid by now, but
- there might be some patents that Zilog filed that were only granted
many years later. These might be still alive. Check USPTO in that case.
Sometimes companies threaten people with patents that were granted, but
for which they stop paying patent fees years ago.
- even when building an old school uC you will likely use modern
concepts some of which might be patented by zilog or others.

Companies like to invoke trademarks and trade secrets in the context.
For the former just make sure that you do not use z8000 as the name of
your processor but use it only in a descriptive way. ("Executes z8000 ISA")
For the latter make sure, that you do not know any trade secrets from
zilog. E.g. that you have never signed an NDA for an z8000 errata sheet
or anything like that.

I would not worry too muc, but h I agree with Peter that it might be a
good idea to try to get zilog on board. They might like what you do and
provide you with advice, contacts, etc.

Kolja Sulimma


Sidenote:
There is a story about a guy who built an Apple-I clone recently and got
sued by apple. When Steve Wozniak realized that he informed the guy that
he never signed off exclusive rights to apple.
Moral: Never believe a company that threatens you. Allways demand proof.

On Fri, 23 Dec 2005 18:20:15 GMT, "Monte Dalrymple"
<monted@systemyde.com> wrote:

[snipped]

>I doubt that those schematics survive though, as they predated
>the era of document control at Zilog.
>

I often wonder how many products never got developed further because
of lost documents at companies. Also how many companies can truly
recover if somwhow they had to start from scratch with only their
documentation in config control.

Regards
  Anton Erasmus

Anton Erasmus wrote:
> "Monte Dalrymple" <monted@systemyde.com> wrote:
> 
> [snipped]
> 
>> I doubt that those schematics survive though, as they predated
>>  the era of document control at Zilog.
> 
> I often wonder how many products never got developed further
> because of lost documents at companies. Also how many companies
> can truly recover if somwhow they had to start from scratch with
> only their documentation in config control.

Believe it or not, adequate documentation and control predates the 
use of computers by a considerable margin.  It involved such things 
as file cabinets with suitably dimensioned drawers to hold original 
drawings, prepared on paper and mylar, sometimes with India Ink, 
the use of Ozalid machines, proper parts list, etc.

-- 
"If you want to post a followup via groups.google.com, don't use
  the broken "Reply" link at the bottom of the article.  Click on
  "show options" at the top of the article, then click on the
  "Reply" at the bottom of the article headers." - Keith Thompson
More details at: <http://cfaj.freeshell.org/google/>

"Chuck F. " <cbfalconer@yahoo.com> wrote in message
news:D4idnfQAhvXC-TDeRVn-pA@maineline.net...
> Anton Erasmus wrote:
> > "Monte Dalrymple" <monted@systemyde.com> wrote:
> >
> > [snipped]
> >
> >> I doubt that those schematics survive though, as they predated
> >>  the era of document control at Zilog.
> >
> > I often wonder how many products never got developed further
> > because of lost documents at companies. Also how many companies
> > can truly recover if somwhow they had to start from scratch with
> > only their documentation in config control.
>
> Believe it or not, adequate documentation and control predates the
> use of computers by a considerable margin.  It involved such things
> as file cabinets with suitably dimensioned drawers to hold original
> drawings, prepared on paper and mylar, sometimes with India Ink,
> the use of Ozalid machines, proper parts list, etc.
>

Oh, the documentation existed, and it was in the control of Shima, the
designer. But once he left the company I don't know who, if anyone,
inherited his filing cabinet. It wasn't until much later that such design
materials were kept in a centralized location with a control number
and access/revision control. Even then, sometimes things went in to
DC never to be found again, so designers hated to give the original
stuff up to DC.

Monte

I collect classic arcade games and am looking to do a remake of the
troublesome Pole Position boardset.  I then stumbled on this page:
www.fpgaarcade.com

and loved the idea.  The PPI and PPII boardsets are Z8000 based.
-Adam
================
 www.onecircuit.com
================

AMD received the transistor diagrams as part of the second-source
agreement, and they then reverse-engineered a logic diagram. (I know,
for I was involved).
AMD is a bigger, and perhaps more organized company.
But this is all some 27 years ago...
Peter Alfke
=============
Monte Dalrymple wrote:
>
> > >> Oh, the documentation existed, and it was in the control of Shima, the
> designer. But once he left the company I don't know who, if anyone,
> inherited his filing cabinet. It wasn't until much later that such design
> materials were kept in a centralized location with a control number
> and access/revision control. Even then, sometimes things went in to
> DC never to be found again, so designers hated to give the original
> stuff up to DC.
> 
> Monte

I looked at doing a conversion of the game, but the main problem is the CPU.
Having done most of the debugging work on the T80 core, which required
running a real cpu in parallel with the soft core and triggering the
analyser when they went separate ways - I can assure you it is a lot of work
to get it cycle accurate.

I am going to release the source of the Namco customs I have reverse
engineered some time soon, some of them are on the Pole Position board which
may help.

Cheers,
MikeJ
www.fpgaarcade.com

"ajcrm125" <ajcrm125@gmail.com> wrote in message
news:1135447235.214449.17090@o13g2000cwo.googlegroups.com...
> I collect classic arcade games and am looking to do a remake of the
> troublesome Pole Position boardset.  I then stumbled on this page:
> www.fpgaarcade.com
>
> and loved the idea.  The PPI and PPII boardsets are Z8000 based.
> -Adam
> ================
>  www.onecircuit.com
> ================
>