An interactive-speed Linux computer made of only 3 8-pin chips

Summary

8-pin Linux An interactive-speed Linux computer on a tiny board you can easily build with only 3 8-pin chips TL;DR I've long been experimenting with minimal computers that can run Linux. I've flirted with the extreme low-end and with fun form factors. I felt like there was a place for another fun experiment: a simple-to-build kit computer using only 8-pin chips. Table of Contents A minimal computerInitial ThoughtsParts SelectionDesigning the hardwareThe ConsoleRAMSD CardThe Console againThe software storyThe EmulatorThe BootloaderCard partitioning and the boot processPerformanceAssemblyAcquisitionInitial assemblySecondary assemblyFlashing the main firmware and first bootDownloads and UseThe filesUsing it... A minimal computer Initial Thoughts There was a time when one could order a kit and assemble a computer at home. It would do just about what a contemporary store-bought computer could do. This time is long gone. Modern computers are made of hundreds of huge complex chips, with no public datasheets, with many hundreds of watts of power supplied to them over complex power delivery topologies. It does not help that modern operating systems require gigabytes of RAM, terabytes of storage, and always-on internet connectivity to properly spy on you. But, what if one tried to fit a modern computer into a kit that one could easily assemble at home? What is the minimum to be considered a "modern computer"? I would say being able to run Debian Linux, vi, gcc, and make is close enough, so that became the goal. Thanks to my previous exploits, I knew that this could be accomplished in 8MB of RAM and with 1 MIPS of CPU. Storage is easy: SD cards easily provide storage of any size. A serial port is still the de-facto method for easily interfacing with an embedded system, but as computers no longer have serial ports, USB-serial takes its place. Thus, I had the target: at least 8MB of RAM, at least 1 MIPS of CPU, SD card, USB. On the hardware front, I wanted to design something th...