Sunday, July 18, 2010

Lazarus-64 Retro Game System - build blog

From idea to prototype

I can still remember the first time I touched the keyboard on a personal computer, watching in amazement as the glowing green screen relayed every character onto the rounded 14 inch glass monitor in front of me. "Syntax Error" was my first response from the 1978 Commodore PET, but it was the very beginning of what would become a life long journey.

While many kids were content to just play the crude games available for the monochrome 1 MHz 6502 based computer, I wanted to dig into the code and understand what went on inside the machine. For weeks I stayed up until the late hours, sitting under the green glow of the cathode ray tube, attempting to alter the source codes, often ending up with random results or a blank screen. Yes, this was the frontier of the hacking age, and I was there for the event horizon. Yah, I'm old!

Fast forward 30 years later, and here I am laying on a secluded Caribbean beach with more free time on my hands than I know what to do with. While some are happy to just shrivel up like raisins in the sun, half baked on Cuba-Libres, I was there with notepad in hand and a calculator melting in he sand beside me! Having just been introduced to the 8 bit microcontroller, I wondered how much of a task it would be to create some kind of retro 8 bit computer like the ones I enjoyed so much as a young nerd.

Although I had not yet done much beyond some simple compiled basic program on the PIC16F84, I had a good idea of how much could be done using assembly and some of the newer 20 MIPs microcontrollers offered by Microchip (PIC) and Atmel (AVR).

Sitting there with a blank notepad looking at the waves crashing against the coral reef it dawned on me that there was more power available in one of these five dollar microcontrollers than any of the 8 bit computers of the early 1980s. Ideas began to take shape on the canvas. Read more...