My first experience with computers was as a ten year old using the families Sinclair ZX80. Through a series of 8-bit home computers I learnt to program first in BASIC and then in Z80 assembler.

Coding on such low-end computers means you’re always close to the hardware, so I always had a rough idea how the hardware worked but never understood it in detail.

This was especially true in the processor. I understood what registers, busses and the ALU were but I never understood how they actually worked. And I never understood how a processor actually executes instructions. Diagrams showed something called ‘control logic‘ and I’d heard the word ‘microcode‘ but, as far as I was concerned this was just a digital form of magic.

Ben Eater’s 8-bit Computer

In 2018 I stumbled across Ben Eater‘s excellent series of educational videos where he leads the viewer through the entire process for constructing a basic 8-bit computer on breadboards.

I was hooked, bought a pile of components and started building.

And Now

This blog is where I’m going to document my adventures in digital logic, 8-bit computers, 8-bit processors and anything related.

The title of this blog is a mash-up between the Z80 processor I spent my teenage years exploring and the breadboards used in electronics. And I realise that to many of you who aren’t British the Z80 is pronounced ‘Zee 80’ and not ‘Zed 80’ so the wordplay fails but I like it so I’m keeping it <g>.

And that combination of Z80s and breadboards gives me a wild and crazy ambition to build a Z80 processor on breadboards out of TTL logic. I have no idea if that’s a realistic idea or even something which is physically possible, but I do love an over the top motivational dream.

I hope you enjoy it and hopefully learn something useful.