Gigatron TTL Computer

Speaker: Walter Belgers

Abstract

What happens when a hacker gets his hands on a heap of 7400-series TTL chips, an oscilloscope and a soldering iron? In 1975 Wozniak famously made Breakout out of 44 such chips. When the MOS 6502 and Zilog Z80 were launched one year later, his Apple 1 started the microcomputer revolution. But were these processor ICs really necessary for that?

One year ago we ordered a bunch of such ICs, bought an oscilloscope and started hacking. The result is a fully functional microcomputer from 36 TTL chips, ROM, RAM, some diodes, etcetera, but most importantly: no microprocessor.

This talk explores the hardware design, the software stack and the capabilities of our result we now call “the Gigatron”. It will give you a good understanding of how a CPU works and what interesting design decisions we have made to keep our CPU small, yet powerful.

Biography

Walter Belgers is a hacker, having worked in IT security for all his life, the majority as a penetration tester and currently as a security officer at Philips. He is also the chairman of Toool, the Open Organisation of Lockpickers. He has been soldering since the 1970s but never before has he built a complete computer.