In the warm glow of the MicroBasement, Don Lancaster’s The 8085A Cookbook stands as one of the most practical microprocessor guides ever written for the homebrew builder. Published in 1980 by Howard W. Sams & Co., this 384-page paperback took the Intel 8085A — a popular, improved successor to the 8080 — and turned it into something approachable and buildable. Lancaster provided complete circuits, timing diagrams, software examples, and troubleshooting tips, making it possible for hobbyists to design, wire, and program their own 8085-based computers without needing an engineering degree or a fortune in parts. It was the book that said: “You’ve got TTL and video down — now let’s make a real microcomputer.”
Don Lancaster (1945–2023) — the prolific master of clear, hands-on electronics — released The 8085A Cookbook in 1980 as part of his “Cookbook” series. Published by Howard W. Sams & Co., it followed the same no-nonsense style that made his TTL, CMOS, TV Typewriter, and Cheap Video books indispensable. By 1980 the 8085 was widely available and affordable, and Lancaster saw the need for a comprehensive, experimenter-friendly guide that bridged the gap between raw datasheets and working hardware. The book became a staple for hobbyists building single-board computers, controllers, and early personal systems.
The book is organized for quick reference and immediate building. It starts with the basics of the 8085A: pinouts, architecture, instruction set overview, clock and reset requirements, power-supply needs, and interfacing rules. Chapters cover memory design (RAM, EPROM, and decoded address spaces), I/O techniques (parallel ports, serial UARTs, keyboard and display interfaces), timing and control signals (WAIT, HOLD, HLDA, READY), interrupt handling, and bus expansion. Lancaster includes complete schematics for several practical 8085A systems — from minimal single-board designs to expanded configurations with video, cassette I/O, and printer ports. Software sections provide assembly-language examples, monitor routines, debugging tips, and utility programs. Appendices list pinouts, timing charts, IC cross-references, and parts sources for the era.
Lancaster’s strength was in the details: he showed exactly how to generate stable clocks (using a 6.144 MHz crystal for 8085 timing), handle multiplexed address/data bus demultiplexing (with 74LS373 latches), build reliable power-on reset, and interface to common peripherals like the 8155 I/O chip or 8279 keyboard/display controller. He emphasized low-cost construction — using surplus parts, wire-wrap, or perfboard — and included real-world troubleshooting for common problems like bus contention or timing glitches. The designs were forgiving and scalable, making them ideal for hobbyists moving up from 8080 kits or building custom controllers.
The 8085A Cookbook represents one of the critical turning points in the personal computing and embedded systems era. By giving hobbyists complete, understandable blueprints for the 8085 — one of the most widely used 8-bit processors of the late 1970s and early 1980s — Don Lancaster empowered thousands to build their own computers, industrial controllers, test equipment, and learning platforms. It bridged the gap from early microcomputer kits to more sophisticated single-board designs and influenced countless homebrew projects worldwide. Preserving and demonstrating this book is essential because it embodies the foundational efforts of writers and engineers who created the pathways for modern computing by making microprocessor design accessible to anyone with a soldering iron. In the MicroBasement, its pages rest beside the TTL Cookbook, TV Typewriter series, and early 8085 hardware — a quiet reminder that practical knowledge, shared generously, can turn a chip into a computer and a hobbyist into a builder.