Originally from pico_effects by @tuupola
If you cannot compile yourself build directory contains a recent firmware for uploading to Galactic Unicorn.
Volume buttons switch between effects.
Zzz button enables or disables auto switching of effects, which is set to 10 seconds and is enabled by default.
Double-click on the reset button to put the Unicorn in bootloader mode.
Brightness is auto-adjusted every second using data from the light sensor on the front right side of the Unicorn (between the Zzz and Volume - buttons).
Brightness buttons are active and when used, auto-adjustment is disabled. To re-enable, click both brightness buttons at the same time. The LEDs will turn off momentarily and brightness will be auto-adjusted.
Below instructions assume you do not have Raspberry Pi Pico SDK nor the Pimoroni Libraries installed yet.
$ git clone --recursive https://github.com/raspberrypi/pico-sdk.git
$ git clone --recursive https://github.com/pimoroni/pimoroni-pico.git
$ git clone --recursive https://github.com/disq/galactic_effects.git
$ cd galactic_effects/build
$ cmake ..
$ make -j8
If they are already installed you can pass the installation path manually.
$ git clone --recursive https://github.com/disq/galactic_effects.git
$ cd galactic_effects/build
$ cmake .. -DPICO_SDK_PATH=../pico-sdk -DPIMORONI_PICO_PATH=../pimoroni-pico
$ make -j8
You can then "flash" the firmware by putting the Galactic Unicorn into BOOTSEL mode and copying the uf2 file to the automatically mounted volume.
$ cp firmware.uf2 /run/media/<username>/RPI-RP2/
If you are using macOS the command would be the following.
$ cp -X firmware.uf2 /Volumes/RPI-RP2
Alternatively you can use picotool to flash the firmware.
$ picotool load firmware.uf2 -f