What ?
The Megaprocessor is a micro-processor built large. Very
large.
How ?
Like all modern processors the Megaprocessor is built from
transistors. It's just that instead of using teeny-weeny ones
integrated on a silicon chip it uses discrete individual ones
like those below. Thousands of them. And loads of LEDs.
Why ? - short
answer : Because I want to.
Why ? - long
answer : Computers are quite opaque, looking at them
it's impossible to see how they work. What I would like to do
is get inside and see what's going on. Trouble is we
can't shrink down small enough to walk inside a silicon chip.
But we can go the other way; we can build the thing big enough
that we can walk inside it. Not only that we can also put LEDs
on everything so we can actually SEE the data moving and the
logic happening. It's going to be great.
Where ? Here.
Cambridge.
Who ? Me. James
When ? Now. As of 22nd June 2016 it is
built. There's a diary of the build progress here. (Last update 20 October 2016)
So how big is it ?
Well an 8-bit adder is about a foot long (I use five of
these):
And the whole thing ?
Currently it's about 10m long and 2m tall:
Does it work ? Yes.
This video gives a little tour of it.
Can I program it ?
Yes. See the programming page
for tools.
Can I see it, play with it
? Yes. And eventually. The Megaprocessor now lives at
the Centre for
Computing History . At this moment in time (Oct 2016)
we're recommissioning the Megaprocessor after its move earlier
this month.
What's next ?
Explaining how it works, starting with a single transistor.
You can see where I've got to with this YouTube
playlist.