The project began in 2012 when James Newman from Cambridge, U.K., decided to build his own computer processor. Using hand-soldered components, Newman aimed to create a functioning system that demonstrates how data travels through a CPU core and ends up being processed.
Four years later, Newman has completed his machine. He has spent over £40,000 on his creation. Over 1,000,000 distinct solder points were joined by hand, linking 42,000 transistors together. 10,500 LEDs adorn the computer units. They light up as data flows through the system, providing a visualisation of how CPUs go about performing tasks.
The room-sized processor contains all the critical components of a general purpose CPU. It features core registers, an arithmetic and logic unit and control and I/O facilities. There’s 256 bytes of memory available. According to Newman, the Megaprocessor runs at speeds of up to 8KHz. It’s usually under-clocked to a mere 1KHz so visitors can watch data flow through the CPU.
Megaprocessor has attracted significant attention during its development. On the project’s homepage, Newman said it’s built to make computers more accessible. Most consumers don’t understand how developers create the apps and programs they use on a daily basis. Many never study transistor operation in detail though. The science of computer architecture is fully appreciated by a tiny fraction of the world’s population.
“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,” said Newman. “Trouble is we can’t shrink down small enough to walk inside a silicon chip. But we can go the other way; we can built 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.”
The Megaprocessor does exactly that. The project has been heralded by computing experts as an innovative way to introduce people to CPU architectures. It is now on display at the Centre for Computing History in Cambridge. The public can now learn about processors by walking in and alongside one.
The completed “chip” is based on the structures of some of the earliest microprocessors, including the Zilog Z80 and Motorola 68000. Its basic instruction set means it can be programmed, allowing Newman to create a game of Tetris that runs on the room-sized computer. In the future, the public will be able to create their own programs using the chip, once its installation at the Centre for Computing History is complete.
