Whizz-80 – a Z80 CPU hand-made computer

Since getting back into electronics, and I enjoy coding, I decided to combine the 2 passions and build my own computer in my spare time: the Whizz-80.

This however isn’t your typical modern day computer that you can just buy part from your local computer shop and plug in and run the latest operating system and software – that would be too easy. Instead I am building a computer right down to the individual chip level, and building it up with its own operating system (Whizz-OS).

Whizz-80 Project Summary:

The Whizz-80 is based on the Z80 CPU, so it has a retro, old school, feel to it which I like. The hardware is simple, there is no fancy DMA or high-speed peripherals.

The Whizz-80 will be based on the Z80 CPU – Old school.

As for the operating system and software, I haven’t got any designs or plans yet at this stage. This will evolve over time and I build and test each component. My current thoughts at this early stage is to create a Forth based Operating System (The ‘Threaded Interpretive Languages’ book has been a great read and learn about how they work).

Open Source:

I intend to open up the project for both hardware and software as open source. I’ve learnt a lot of information online from other people who have opened up their designs on the web, so I feel it is only fair that I also make my schematics and code available for others to learn and use.

Whizz-80 Hardware Specs:

  • Z80 CPU (6Mhz)
  • 32Kb ROM memory
  • 32Kb RAM memory
  • Custom I/O board

Whizz-80 Software Specs:

  • Home grown OS (Whizz-OS yet to be built)

A great site to learn all about the z80 comes from Thomas Scherrer’s z80 site, which is a great collection of articles, diagrams, source code and general z80 stuff.

Surprisingly I have found a lot of information not on the net, but located in dead trees (books). Here are some of the books I have used as reference and guides to build this system, both software and hardware:

The construction blog of the Whizz-80 computer is available here

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