BreezyBox shell demo for ESP32-S3
This is a demo for how you can turn an ESP32-S3 microcontroller into a tiny instant-on PC with its own shell, editor, compiler, and online apps installer. Something like Raspberry Pi, minus the overhead of a full server/desktop grade OS. I think ESP32 is underrated in hobby maker community for this PC-like use case. This demo uses BreezyBox, my mini-shell ESP-IDF component.
That sounds too good to be true. What is BreezyBox anyway?
First of all, seeing is believing (click to watch the video):
It started as a "cyberdeck" style crafting project. Then I got carried away with the software part. I chose ESP32-S3 for the base platform. It has the nostalgic appeal of the DOS era PCs, with similar resources, and elbow-deep-in-bytes coding experience, plus modern wireless comms.
ESP32-S3 can do everything those PCs did and more, but that is inconvenient out of the box, because that is not the commercial use case it is positioned for. It also forces away the code bloat. If you are like me, and love small elegant things, and technology that punches way above its weight, you ought to try it!
So anyway, I decided to try and package some key missing parts: a basic vterm, the current working directory (CWD) tracking, a few familiar UNIX-like commands, and an app installer. Believe it or not, the rest is already there in ESP-IDF components, including the elf_loader with dynamic linking.
The result is called "BreezyBox", by analogy with the BusyBox commands suite. The name is just a light joke, it is not meant to be a full clone. You can import it with one command in your ESP-IDF project, and if you have some stdio going, even at "Hello World" level, it should mostly just work. I call it a "mini shell", a naïve user might call it an OS (it is not, it runs on FreeRTOS), and you can also call it the userland layer.
This repo is just one possible example
The BreezyBox component leaves the display and other board configuration details to the user's firmware project, providing mainly the vterm/vfs features, and some shell commands. This particular example/demo project supports only one specific dev board: Waveshare ESP32-S3-Touch-LCD-7B (no affiliation). But you can see how all the parts connect, and adapt it to your display/board, or just copy some code snippets from here.
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