Building an 8‑Bit CPU from Scratch: A Hands‑On Guide

Inspired by Ben Eater’s famous tutorial, the author set out to build a working 8‑bit CPU entirely by hand, aiming to deepen understanding of computer architecture and gain hands‑on experience with electronics.

The project began with sourcing components listed on Eater’s site, which required translating U.S. part numbers into Chinese equivalents; the author shares screenshots of the parts list and notes the difficulty of finding suitable components locally.

Following the video series, the build proceeds module by module: starting with a 555‑timer clock circuit, then constructing registers using 74LS173 and 74LS245 chips, and finally wiring the entire bus and control logic. The author includes several photos of the breadboard at different stages, showing the clock module, register connections, and the completed prototype.

For absolute beginners, the article explains how to identify resistor colour codes, differentiate capacitor types (electrolytic, ceramic, etc.), and choose appropriate wire lengths, recommending bulk wire that can be cut to size rather than pre‑cut leads.

The entire construction took about two months, with roughly half an hour of work each weekday and longer sessions on weekends. The author emphasizes that the process is not as daunting as it seems and that completing the CPU clarified many previously abstract concepts in computer organization.

Resources provided include the original tutorial site (https://eater.net/), a Chinese‑subtitled version on Bilibili, and practical advice such as avoiding fixed‑length jumper wires to keep the layout tidy. The author encourages readers to try the project for both educational insight and the satisfaction of building a functional processor.