Building MicroPython

... for the Raspberry Pi Pico microcontroller

The following instructions briefly explain how to build the current MicroPython firmware for the rp2040 Pico board and include the ulab math/vector library and the libraries for the pico display pack module.

These instructions were compiled from here and here. They were tested using Ubuntu 20.4 installed in the Linux Subsystem of Windows 10.

1. To keep different MicroPython ports separated, using a folder for each is recommended. Here, we install the tools in the folder pico.

   mkdir pico
   cd pico/
   

2. Make sure your installation is up to date:

   sudo apt update
   sudo apt install cmake gcc-arm-none-eabi build-essential
   

3. Clone and prepare the pico SDK:

   git clone -b master https://github.com/raspberrypi/pico-sdk.git
   export PICO_SDK_PATH=~/pico/pico-sdk
   cd pico-sdk
   git submodule update --init
   

4. Clone and prepare MicroPython:

   cd ~/pico
   git clone https://github.com/micropython/micropython
   cd micropython
   git submodule update --init lib/tinyusb
   git submodule update --init lib/pico-sdk
   cd lib/pico-sdk
   git submodule update --init
   git submodule update --init lib/tinyusb
   cd ../../mpy-cross
   make -j 8
   

5. Clone and prepare the Pimoroni repository:

   cd ~/pico
   git clone https://github.com/pimoroni/pimoroni-pico.git
   

6. Clone the ulab repository into a subfolder of the Pimoroni folder :

   cd ~/pico/pimoroni-pico/micropython/modules/
   rm -r -f ulab
   git clone https://github.com/v923z/micropython-ulab ulab
   

7. Build the firmware:

   cd ~/pico/micropython/ports/rp2
   make clean
   make -j 8 USER_C_MODULES=../../../pimoroni-pico/micropython/modules/micropython.cmake
   

8. Deploy the firmware:

   Open a Windows explorer window:

   explorer.exe .
   

   The file firmware.uf2 in the folder build contains the firmware image.

   Disconnect the Pico board from the USB cable, press the button on the board and keep it pressed while plugging in the USB cable. After releasing the button, a drive RPI-RP2 pops up. Drag the file firmware.uf2 onto that drive. The board should restart and offer the MicroPython REPL.