LV (Light and Versatile Graphics Library) MicroPython for M5Stack Core2

Use of the custom firmware

Install esptool.py via pip. Connect the M5Stack Core2 via USB. Load the custom firmware using esptool.py specifying the correct tty:

esptool.py --chip esp32 --port /dev/tty.usbserial-6952FF0E93 erase_flash
esptool.py --chip esp32 --port /dev/tty.usbserial-6952FF0E93 write_flash -z 0x1000 ~/firmware/lv_micropython_1.14_168aa6a_esp32_idf4.0_m5stack_m5core2.bin

For a demo of the firmware, transfer main_test.py to the Core2 using ampy or your favorite CLI.

Setup for compilation of the custom firware

This is only necessary if you want to build the firmware for yourself, for example in case you want to upgrade to a more recent micropython firmware.

You will need:

• An Ubuntu linux environment, preferably (I tested on Ubuntu 20.04)
• A set of development tools on Ubuntu (see below)
• esp-idf4, patched with files contained in this repo (source/esp-idf_components)
• lv_micropython or micropython, patched with files contained in this repo (micropython_ports)

Install the build environment

sudo apt-get install build-essential libreadline-dev libffi-dev git pkg-config libsdl2-2.0-0 libsdl2-dev python3.8

Clone lv_micropython repository

git clone --recurse-submodules https://github.com/littlevgl/lv_micropython.git

Set up esp_idf4 toolchain and compiler

See https://lemariva.com/blog/2020/03/tutorial-getting-started-micropython-v20

Patch esp_idf4

Files contained in esp-idf_components go into ~/esp-idf/components.

Patch lv_micropython

Files contained in micropython_ports/esp32 go into ~/lv_micropython/ports/esp32.

Compile lv_micropython

cd ~/lv_micropython

export BOARD=M5CORE2_BOARD

make -C mpy-cross
make -C ports/esp32 LV_CFLAGS="-DLV_COLOR_DEPTH=16 -DLV_COLOR_16_SWAP=1" PYTHON=python3

The generated firmware will be located in ports/esp32/build-M5CORE2_BOARD/firmware.bin.