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.
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.
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:
- Build your own Z80 – Steve Ciarcia
- Z80 assembly language programming – Lance A Leventhal
- Threaded Interpretive Languages: Their Design and Implementation – R. G. Loeliger
The construction blog of the Whizz-80 computer is available here