steinuil/watchy-rs

[WIP] Rust firmware for the Watchy

esp32-hal documentation

• https://docs.rs/esp32-hal/latest/
• https://docs.rs/esp32/latest/

Data sheets and crates

https://watchy.sqfmi.com/docs/hardware

• Microcontroller ESP32-PICO-D4
• E-Paper Display GDEH0154D67 SSD1681
  • https://docs.rs/gdeh0154d67/latest/gdeh0154d67/
  • https://gitlab.com/CasalI/gdeh0154d67
  • https://github.com/ZinggJM/GxEPD/blob/master/src/GxGDEH0154D67/GxGDEH0154D67.cpp
• Real time clock PCF8563
  • https://docs.rs/pcf8563/latest/pcf8563/
• 3-axis accelerometer BMA423
  • https://docs.rs/bma423/latest/bma423/

esp toolchain on Nix

• https://github.com/sdobz/rust-esp-nix (3 years old)
• https://github.com/kate-shine/nix-esp32 (uses the docker image)
• https://n8henrie.com/2023/09/compiling-rust-for-the-esp32-with-nix/ (doesn't support xtensa architectures)

TODO

• BMA423
  • test on the Watchy
  • add states for initialized/fullpower/powersave like in the non-async crate
• GDEH0154D67:
  • partial updates
  • lots of configurability stuff
  • could try doing grayscale by manipulating the border waveform
    • https://hackaday.io/project/11537-nekocal-an-e-ink-calendar/log/72153-can-you-get-32-level-grayscale-out-of-an-e-ink-display
    • https://github.com/zkarcher/FancyEPD
• PCF8563
  • better error handling
  • functionality missing
  • provide the raw time/date numbers from the registers and add a time feature that enables support for the time crate
• Wi-fi and BLE: https://github.com/esp-rs/esp-wifi