A wireless CNC pendant with LVGL GUI

Very much a work in progress.

Uses two ESP32, one with screen for UX, the other as wireless-serial-bridge. Uses ESP-NOW as the wireless comms.

In the flesh

Pendant in a 3D printed case:

Example Probing Screens:

Building

LVGL+Micropython

WT32-SC01 Plus:

Download/clone lvgl-micropython

• git clone https://github.com/lvgl-micropython/lvgl_micropython.git

Optional: Patching Micropython to support PCNT (pulse counter) for faster encoder reading

• Without this patch, the encoder rate is limited and may miss steps - but this step is optional!
• curl -O "https://patch-diff.githubusercontent.com/raw/micropython/micropython/pull/7582.diff" (in lvgl_micropython directory),
• git apply 7582.diff to apply the diff.

Building micropython+lvgl

• python3 make.py esp32 BOARD=ESP32_GENERIC_S3 DISPLAY=st7796 INDEV=ft6x36 --flash-size=16 (tested with Python 3.13)
  • (ends in a couple errors + "unable to locate python version used in the ESP-IDF" but afaict that's just the flashing failing and binaries are built!).

Unix/MacOS:

• python3.13 make.py macOS DISPLAY=sdl_display INDEV=sdl_pointer or
• python3.13 make.py unix DISPLAY=sdl_display INDEV=sdl_pointer.

Flashing

Prerequisites

• UV python package manger (apt-get install uv, brew install uv, ...),
• esptool.py (uv tool install esptool).

WT32-SC01 Plus:

• Boot SC01 Plus into proramming mode (short GPIO0 / BOOT0 to GND before and during boot, then let go, esptool.py should now find the ESP32S3 - see online docs for pinout),
• esptool.py --chip esp32s3 -b 460800 erase_flash,
• cd ./lib/micropython/ports/esp32 from lvgl_micropython main directory,
• esptool.py --chip esp32s3 -b 460800 --before default_reset --after no_reset write_flash --flash_mode dio --flash_size 16MB --flash_freq 80m 0x0 build-ESP32_GENERIC_S3/bootloader/bootloader.bin 0x8000 build-ESP32_GENERIC_S3/partition_table/partition-table.bin 0x10000 build-ESP32_GENERIC_S3/micropython.bin,
• restart WT32-SC01 Plus mpremote should now be able to get into the micropython repl after boot.

Copy files

• Install mpremote (uv tool install mpremote).
• mpremote connect /dev/<ttyid> fs cp -r * :
• mpremote connect /dev/<ttyid> reset

(Or copy files one-by-one)

• mpremote fs cp firmware/wt32_sc01_plus/encoder.py :encoder.py,
• mpremote fs cp firmware/wt32_sc01_plus/lv_style.py :lv_style.py,
• mpremote fs cp firmware/wt32_sc01_plus/rrf_machine.py :rrf_machine.py,
• mpremote fs cp firmware/wt32_sc01_plus/main.py :main.py,
• ...
• mpremote reset.

Running, Testing and Development

Unix/Macos

• cd firmware/wt32_sc01_plus
• lvgl_micropy_macOS main.py

Acknowledgements

• LVGL-micropython: https://github.com/lvgl-micropython/lvgl_micropython
• Google Fonts/Material Symbols used as images for probe buttons: https://developers.google.com/fonts/docs/material_symbols