Since I like playing around with electronics, and I enjoy learning new things with coding, I decided to combine the 2 passions and build my own computer in my spare time: the Whizz80.
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 (WhizzOS).
Whizz80 Project Summary:
The Whizz80 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.
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).
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.
Whizz80 Hardware Specs:
- Z80 CPU (6Mhz)
- 32Kb ROM memory
- 32Kb RAM memory
- Custom I/O board
Whizz80 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:
- Build your own Z80 – Steve Ciarcia
- Z80 assembly language programming – Lance A Leventhal
- Threaded Interpretive Languages: Their Design and Implementation – R. G. Loeliger