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.

The Megaprocessor has featured in a several articals, for example: The Register , the BBC News web site, IEEE Spectrum



