Embedded Swift on PicoSystem

The PicoSystem is a small handheld gaming device created by Pimoroni for hobbyists. It is powered by an RP2040 microcontroller, the same as found on the Pico boards from Raspberry Pi.

This example demonstrates a small Embedded Swift application for the PicoSystem, using the PicoSystem and Pico SDKs via Swift's interop abilities.

Requirements

• Follow the setup steps at https://datasheets.raspberrypi.com/pico/getting-started-with-pico.pdf. You'll need:
  • A checkout of the Pico SDK, with git submodules checked out.
  • CMake.
  • The Arm Embedded Toolchain.
• Follow the steps to set up the PicoSystem SDK at https://github.com/pimoroni/picosystem?tab=readme-ov-file#getting-started.
• Before trying to use Swift with the PicoSystem, make sure your environment works and can build the PicoSystem examples.

Building

Make sure you have a recent nightly Swift toolchain that has Embedded Swift support.

$ cd swift-picosystem-example
$ export TOOLCHAINS='<toolchain-name>'
$ export PICO_BOARD=pico
$ export PICO_SDK_PATH='<path-to-your-pico-sdk>'
$ export PICO_TOOLCHAIN_PATH='<path-to-the-arm-toolchain>'
$ export PICOSYSTEM_DIR='<path-to-your-picosystem-sdk>'
$ cmake -B build -G Ninja .
$ cmake --build build

Running

• Connect the PicoSystem via a USB cable to your computer.
• Hold down the X button on the PicoSystem and press the power button. This will turn the PicoSystem on in the USB Mass Storage firmware upload mode.
• Copy the UF2 firmware to the Mass Storage device:

$ cp build/swift-blinky.uf2 /Volumes/RPI-RP2

• The application should begin running on the PicoSystem.

A Note About the PicoSystem SDK

Due to C++ name mangling differences between Clang and g++, a C layer is used to wrap the PicoSystem SDK calls used in this example. I'm continuing to look into ways to remove this requirement.

Acknowledgments

Special thanks to Kuba Mracek (@kubamracek) and Rauhul Varma (@rauhul) for their Embedded Swift examples.