A 16-control subtractive synth for microcontrollers (39k ELF, web demo)
This toy retro synth installs and runs on esp32-s3 or p4 as an ELF file under BreezyBox firmware. It uses my work-in-progress immediate mode TUI library in C. Web-based version via emscripten: https://mini000.itch.io/beeper Source code: https://github.com/valdanylchuk/beeper Demo video running on Tanmatsu (esp32-p4): https://www.youtube.com/watch?v=uCH9XYZ7QB0 The main challenge I was going for was actually to find a nice minimal set of controls for a subtractive synth. Usually there are 40-50 of them in "simple" synths; I ended up with 16.…
What it does
In the maker’s words, at launch
This toy retro synth installs and runs on esp32-s3 or p4 as an ELF file under BreezyBox firmware. It uses my work-in-progress immediate mode TUI library in C. Web-based version via emscripten: https://mini000.itch.io/beeper Source code: https://github.com/valdanylchuk/beeper Demo video running on Tanmatsu (esp32-p4): https://www.youtube.com/watch?v=uCH9XYZ7QB0 The main challenge I was going for was actually to find a nice minimal set of controls for a subtractive synth. Usually there are 40-50 of them in "simple" synths; I ended up with 16. In terms of TUI, I wanted to see if it would be practical at embedded C scale to use a modern approach similar to ratatui, Dear ImGui, or Nuklear. I am quite happy with it so far. Will keep using and extending it for more embedded apps. I did not publish the library as a separate project yet; it is not mature enough. Feel free to reuse it via good old copying for now if you like it. For those who remember my earlier post here about the BreezyBox ( https://news.ycombinator.com/item?id=46918429 ), a few updates from the last 6 months: * added sshd for inbound connections * extended shell with variables, loops, conditions, tar, grep, diff * added sound component, including pico8-themed sequencer, and a few example apps * ported my self-hosting C compiler for RISC-V (rcc700) * shared a full example firmware project for Tanmatsu (p4), in addition to earlier Waveshare (s3) Thanks for checking this out! I welcome any questions and feedback about the synth app, the TUI library, or the Breezybox firmware.
Does the same job
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Write up of an embedded project I made to control my analogue synthesizer. Happy to answer any questions or provide any further details of this project if wanted.
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