

Mark 1 FORTH Computer - Cieplak
http://www.holmea.demon.co.uk/Mk1/Architecture.htm

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rbanffy
One of my graduation projects was a processor. Halfway through the design, I
decided to ditch most of the registers and make it into a mostly stack-based
machine. Since it was never built (the project was to _design_ a processor), I
imagine it was very far from buildable. It would probably be expensive for the
late 80's too - the printed OrCAD files occupied an area larger than my room
and chip count was a couple hundred ICs.

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aklein
Killer! Does anyone know good (free) software to build a computer
(simulation), to test a design? Did you utilize any software in your specs?

~~~
noselasd
There's a lot of CPUs around in VHDL or Verilog, e.g.

* <http://opensource.zylin.com/zpu.htm>

* <http://www.altera.com/devices/processor/nios2/ni2-index.html>

You could use ghdl , <http://ghdl.free.fr/>, and supporting tools for
simulation. Most FPGA vendors have a free version of their tools as well.

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femto
Apart from being a neat project, this is a good demonstration of how far we
have come since TTL. Today you can buy a ten pack of 144 forth computers on a
single chip (= 1440 CPUs) for USD200 [1]. Each asynchronous CPU has a claimed
instruction cycle of ~1.8ns, giving each array of 144 CPUs a peak of 96
billion operations per second with 650mW dissipated.

I don't write this to belittle the Mark 1. I just love the juxtaposition of
old and new.

[1] <http://www.greenarraychips.com/home/products/index.html>

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marshray
It's a bit of an unfair comparison. The Mark 1 has something like 200 times
more RAM per CPU.

~~~
marshray
That wasn't a joke.

