using an FPGA to emulate a vintage computer

Fri Feb 05, 2010 9:19 pm   

Has anyone created a copy machine of an old system using an FPGA? I
was wondering if it would be possible to take an entire SWTPC 6800 and
compile the schematics and have it run on an FPGA board.? Wouldn't
even have to be the latest Xylinx product, I suspect.

Fri Feb 05, 2010 9:19 pm   

On 05/02/2010 18:19, in article
badc12c3-cb2b-4ce9-9543-237d60fc22d5_at_o8g2000vbm.googlegroups.com, "Eric
Chomko" <pne.chomko_at_comcast.net> wrote:


I think such a project would valuable, and perhaps even more valuable if it
aimed to recreate a machine of the "heroic" era -- a 7094, an Atlas, or a
KDF9, say. Perhaps even a Stretch.

KDF9 had about 20K transistors, a few K logic transformers, and a comparable
number of diodes; less than 50K devices in total. I imagine this would be
easily accommodated on a modern FPGA. The big question would be whether to
go for functional equivalence, or whether to try to replicate the original
internal structures.

Documentation would be the main challenge for the latter.

--
Bill Findlay
<surname><forename> chez blueyonder.co.uk

Fri Feb 05, 2010 9:19 pm   

["Followup-To:" set to comp.arch.fpga.]
Eric Chomko <pne.chomko_at_comcast.net> wrote:

There are several such projects, eg. this Atari ST clone:
http://www.experiment-s.de/en/

so most systems from the 8-bit era should be no problem at all.

cu
Michael

Fri Feb 05, 2010 10:10 pm   

On Fri, 5 Feb 2010 10:19:25 -0800 (PST), Eric Chomko
<pne.chomko_at_comcast.net> wrote:

|Has anyone created a copy machine of an old system using an FPGA? I
|was wondering if it would be possible to take an entire SWTPC 6800 and
|compile the schematics and have it run on an FPGA board.? Wouldn't
|even have to be the latest Xylinx product, I suspect.


John Kent has done a lot of work using Xilinx chips and synthesizing a
6809 version of the SWTPC onto a chip.

See his webpage here

http://members.optusnet.com.au/jekent/system09/

There is also a yahoo group that is centered around the Tandy CoCO3 on
a Digilent Spartan 3 starter board with the XC3S1000 chip option. The
yahoo group is known as CoCo3fpga I think.

james

Sat Feb 06, 2010 12:57 am   

In comp.arch.fpga Eric Chomko <pne.chomko_at_comcast.net> wrote:

I haven't done it yet, but I am interested. I have a Digilent
Spartan3E board for that purpose. I think it is big enough for
the whole system for many of those machines.

-- glen

Sat Feb 06, 2010 2:33 am   

Eric Chomko wrote:

No fpga, but same idea:
http://www.grc.com/pdp-8/pdp-8.htm


-- Mike Treseler

Sat Feb 06, 2010 2:57 am   

Eric Chomko wrote:

I did. Some 8 years ago.

http://alexfreed.com/FPGApple/

And then a few other vintage computers.

-Alex.

--- news://freenews.netfront.net/ - complaints: news_at_netfront.net ---

Sat Feb 06, 2010 2:59 am   

"Eric Chomko" <pne.chomko_at_comcast.net> wrote in message
news:badc12c3-cb2b-4ce9-9543-237d60fc22d5_at_o8g2000vbm.googlegroups.com...

There have recently been some discussions along these lines in the
comp.lang.modula2 newsgroup regarding different ways of re-implementing a
Lilith.

Also MiniMig is an Amiga 500 re-implemented using an FPGA.

http://en.wikipedia.org/wiki/Minimig

--
Chris Burrows
CFB Software
http://www.cfbsoftware.com/modula2

Sat Feb 06, 2010 12:23 pm   

"Mike Treseler" <mtreseler_at_gmail.com> wrote in message
news:7t3rmlFhriU1_at_mid.individual.net...

Looking at the PDP8 picture brings back bad memories of me helping to clear out
the computer lab at my old University which was full of PDP8 and PDP11, it all
went into the skip......;-(

Hans
www.ht-lab.com

Sat Feb 06, 2010 1:34 pm   

On 5 Feb, 18:19, Eric Chomko <pne.cho...@comcast.net> wrote:


Like Alex Freed this person made an Apple 2 on FPGA

http://www.cs.columbia.edu/~sedwards/apple2fpga/

An amazing project however one looks at it. The power consumption
figures are interesting.

James

Sat Feb 06, 2010 2:29 pm   

On Feb 6, 1:19 am, Eric Chomko <pne.cho...@comcast.net> wrote:

It's the answer to a different question of course,
but a National Semiconducter subsidiary once tried to
emulate an IBM 3033 at full speed using Fairchild 100k parts.
.... the reason for failure is interesting ...

James Dow Allen

Sat Feb 06, 2010 2:35 pm   

Eric Chomko <pne.chomko_at_comcast.net> wrote:


Many people already did that.

http://www.hat.hi-ho.ne.jp/tujikawa/esepld/esemsx2/

--
Failure does not prove something is impossible, failure simply
indicates you are not using the right tools...
nico_at_nctdevpuntnl (punt=.)
--------------------------------------------------------------

Sat Feb 06, 2010 3:23 pm   

On Fri, 05 Feb 2010 16:33:24 -0800, Mike Treseler wrote:


Wow, thanks for that wonderful link, and thanks to
the wonderful but certifiably deranged people who
put together all those resources. I cut my teeth
on PDP8s in various forms; FOCAL was my first
programming language; a PDP8/a (yes, I know, not
a real classic but a nice Classic nonetheless) was
the first computer whose guts I got to mess with.
That one was mostly 74-TTL, with quite a lot of
small bipolar PROMs for its state machines.
(For the youngsters: "small" here means 256 byte
or thereabouts. Byte, not kilobyte, please note.)

And I totally agree with all the hagiography on
that site celebrating the 8's superb economy of
design, in the days when that desperately mattered.
It spilt over into programming too. OS/8 required
you to write device drivers in only 256 12-bit
words; I managed to do one of those myself.
DEC got the entire FORTRAN runtime library into
only 4K of (self-modifying!!) code.

Sorry, I'm rambling. I'm still on a nostalgia high
after a visit to the fabulous collection of old
computer equipment in the Deutsches Museum in
Munich a couple of weeks ago. Strangely, though,
they had no DEC equipment at all!
--
Jonathan Bromley

Sat Feb 06, 2010 7:10 pm   

On 2/6/10 3:29 AM, James Dow Allen wrote:

I would be interested in what the reason for failure was.
I assume it wasn't the obvious chip-chip delays using commodity
ICs.

Sat Feb 06, 2010 8:15 pm   

James Dow Allen <jdallen2000_at_yahoo.com> writes:

in the early 80s los gatos did custom hardware for chip logic simulation
(LSM ... "losgatos state machine" ... then "logic simulation machine"
for publication) ... dozen plus rack boxes ... ran 50,000 times faster
faster than logic simulation in software on 3033

this mentions putting 4.5 meter dish in back parking lot of los gatos
lab (and on east coast in field near yorkton research).
http://www.garlic.com/~lynn/2010c.html#57 watches

a dish also went into austin ... and austin credits the link and access
to hardware logic simulation (relatively high bandwidth for the period
.... for transmission of chip design files) with helping bring in the
RIOS chipset 12 months early ... recent reference to six chipset RIOS
(aka POWER, used in rs/6000).
http://www.garlic.com/~lynn/2010c.html#20 Processes' memory

later hardware logic simulators assumed synchronous clock ... but the
LSM had clock support ... allowed simulation of digital chips with
analog circuits ... (the then) new generation of thin-film disk heads
and chips with non-globally synchronous circuit.

however, the 3033 in bldg. 15 (disk product test lab) was used for air
bearing software simulation (shape for floating disk heads) ... misc.
past posts getting to play disk engineer in bldgs. 14&15
http://www.garlic.com/~lynn/subtopic.html#disk

misc. past posts mentioning LSM
http://www.garlic.com/~lynn/2002d.html#3 Chip Emulators - was How does a chip get designed?
http://www.garlic.com/~lynn/2002g.html#55 Multics hardware (was Re: "Soul of a New Machine" Computer?)
http://www.garlic.com/~lynn/2002g.html#77 Pipelining in the past
http://www.garlic.com/~lynn/2002g.html#82 Future architecture
http://www.garlic.com/~lynn/2002j.html#26 LSM, YSE, & EVE
http://www.garlic.com/~lynn/2003.html#31 asynchronous CPUs
http://www.garlic.com/~lynn/2003k.html#3 Ping: Anne & Lynn Wheeler
http://www.garlic.com/~lynn/2003k.html#14 Ping: Anne & Lynn Wheeler
http://www.garlic.com/~lynn/2003o.html#38 When nerds were nerds
http://www.garlic.com/~lynn/2004j.html#16 US fiscal policy (Was: Bob Bemer, Computer Pioneer,Father of ASCII,Invento
http://www.garlic.com/~lynn/2004o.html#25 CKD Disks?
http://www.garlic.com/~lynn/2004o.html#65 360 longevity, was RISCs too close to hardware?
http://www.garlic.com/~lynn/2005c.html#6 [Lit.] Buffer overruns
http://www.garlic.com/~lynn/2005d.html#33 Thou shalt have no other gods before the ANSI C standard
http://www.garlic.com/~lynn/2006q.html#42 Was FORTRAN buggy?
http://www.garlic.com/~lynn/2006r.html#11 Was FORTRAN buggy?
http://www.garlic.com/~lynn/2007f.html#73 Is computer history taught now?
http://www.garlic.com/~lynn/2007h.html#61 Fast and Safe C Strings: User friendly C macros to Declare and use C Strings
http://www.garlic.com/~lynn/2007l.html#53 Drums: Memory or Peripheral?
http://www.garlic.com/~lynn/2007m.html#58 Is Parallel Programming Just Too Hard?
http://www.garlic.com/~lynn/2007m.html#61 Is Parallel Programming Just Too Hard?
http://www.garlic.com/~lynn/2007n.html#22 What if phone company had developed Internet?
http://www.garlic.com/~lynn/2007o.html#67 1401 simulator for OS/360
http://www.garlic.com/~lynn/2007o.html#68 CA to IBM TCP Conversion
http://www.garlic.com/~lynn/2008c.html#68 Toyota Beats GM in Global Production
http://www.garlic.com/~lynn/2009k.html#75 Disksize history question
http://www.garlic.com/~lynn/2009m.html#63 What happened to computer architecture (and comp.arch?)

--
42yrs virtualization experience (since Jan68), online at home since Mar1970