Prithvi Jamadagni's Webpage

Howdy, and welcome to my website!

The CP/M-80 Project

Conception

This project was mainly inspired by Charles Petzold's book, CODE: The Hidden Language of Computer Hardware and Software. This book details the inner workings of computers, starting at the most basic level with switches and lightbulbs, and working up through boolean logic, gates, hexadecimal, and finally the Intel 8080 CPU. One of the things detailed in the book is a binary adder made from logic gates, to demonstrate a simple part of the 8080 CPU, the accumulator. I was inspired to replicate this adder on a slightly smaller scale in 6th grade. More recently, I was inspired to build a full computer around the 8080.

Resources

The most important resource I've had for this project is Grant Searle's page about his Z80-based CP/M build. My computer is a direct replica of his, found at his page. I'm also using his Atmega-based keyboard/display serial terminal, found here. Another huge help was the crew at the Team Ten discord server, who've been involved with many builds before such as the Alice computer and many other retro computing projects. They answered tons of questions about everything from part compatibility to build advice, and I couldn't have done this without them.

Version 1.0

First, I'll just be putting together the bare minimum circuit as a proof of concept. I've purchased all of the hardware and completed most of the preliminary programming. All I have left is writing an Arduino script to flash the boot ROM, and then final assembly and testing.

Beyond 1.0

I'd like to make a smooth black polycarb casing with some LED illumination inside, to add to the "retro-future" design. I'd also design custom PCBs for the computer, following a design similar to the RC2014 ecosystem with its backplane and daughterboards layout (which really harkens back to the S-100 bus of the Altair 8800). As part of this new design, I have plans to create a sound card for the computer using a PSG chip like the YM2149 or YM2608/OPNA. I might even write a custom OS for the machine.