Z80 System
Part 1 - How it began and why

It's since I am 18 or so I was saying myself "one day I'll build my own little computer with a Z80". For various reasons .. I never did it .. it always been one of those situations "one day I will" and this day never coming.

But finally that day came around the eve of December 2007, the main event that triggered all was I found an affordable EPROM+various things programmer on Ebay and I decided to get it. Then, I was contemplating this old box full of chips waiting for their moment to become something alive.

Finally a voice in my head told me "you are not going to die without doing this" .. and so it began, two days scribbling ideas and such and checking "all that I had around the desk" and the very basic prototype started to get life. The basic was literally basic, a clock oscillator, 8K Ram and 8K rom plus a 7 segments display just enough to see that something was working and capable to run stuff.

The basic system
I/O decoder, clock, CPU, address decoder, ROM, RAM, Latch

This setup was already capable to run code but other than just counting numbers and such it wasn't very useful however it was the basic starting point, you can see how it was looking underside. That was the only wire I had around at the moment, it's multi strand wire ..

Basic, bottom view
Solder side, shielding for the clock oscillator

The reason for that notch is incredibly trivial, that was the only one matrix board left I had and I really can't remember when/for what I cut out that piece before. Remember all this been done with the pieces I had around the desk, literally.

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