There a two branches with code relevant to this project:

• The fruit_jam branch, which contains the bare minimum to run Pico-Faces on the Fruit Jam and control it over USB serial. It does not display a face by default on boot up. To render a face, connect via USB serial to the device and send a capital "G" then press enter. This would be the best branch to build from if you want to take the bare Pico-Faces image generation and make something different from it on the Fruit Jam.
• The color_grid_mode branch, which contains the full 2x2 color grid demo. This one does render the first face on boot up automatically. It also provides controls using the built-in buttons to change rendering modes and color style, so it can be used without a host computer or USB serial. Start from this branch if you want to customize the demo behavior or make custom color styles.

Building

Building the Pico-Faces project is a two step process. First configure the build, and then run it to make the firmware files. There are a few requirements to set up before the first build.

Clone a specified branch of the project using the following command. Replace color_grid_mode with fruit_jam if you want the bare Fruit Jam and DVI support without the 2x2 grid demo with button controls. 

git clone -b color_grid_mode https://github.com/adafruit/pico-faces.git

git clone -b color_grid_mode https://github.com/adafruit/pico-faces.git

Requirements

Clone the pico-sdk repo and fetch the tinyusb submodule inside of it using the following commands.

git clone https://github.com/raspberrypi/pico-sdk.git

cd pico-sdk
git submodule update --init lib/tinyusb
cd ../

git clone https://github.com/raspberrypi/pico-sdk.git

cd pico-sdk
git submodule update --init lib/tinyusb
cd ../

Configure & Build

These commands will let the environment know where to find pico-sdk, configure a build, and then make the build.

Update the value of PICO_SDK_PATH to point to the pico-sdk repo that was cloned in the previous step if it isn't in home directory at ~/pico-sdk/.

export PICO_SDK_PATH=~/pico-sdk/

# building on x86_64
cmake -S firmware -B build/fruitjam -G "Unix Makefiles" -DPICO_BOARD=adafruit_fruit_jam -DRF_DVI=1 -DRF_VGA=0 -DMODEL_BIN=$PWD/checkpoints/m3_decD_deep_full/model.bin -DCMAKE_BUILD_TYPE=Release -DPICOTOOL_FORCE_FETCH_FROM_GIT=1

# building on ARM like RPi
# cmake -S firmware -B build/fruitjam -DCMAKE_BUILD_TYPE=Release -DRF_DVI=1 -DRF_VGA=0 -DPICO_BOARD=adafruit_fruit_jam -DMODEL_BIN=$PWD/checkpoints/m3_decD_deep_full/model.bin

cmake --build build/fruitjam -j4

export PICO_SDK_PATH=~/pico-sdk/

# building on x86_64
cmake -S firmware -B build/fruitjam -G "Unix Makefiles" -DPICO_BOARD=adafruit_fruit_jam -DRF_DVI=1 -DRF_VGA=0 -DMODEL_BIN=$PWD/checkpoints/m3_decD_deep_full/model.bin -DCMAKE_BUILD_TYPE=Release -DPICOTOOL_FORCE_FETCH_FROM_GIT=1

# building on ARM like RPi
# cmake -S firmware -B build/fruitjam -DCMAKE_BUILD_TYPE=Release -DRF_DVI=1 -DRF_VGA=0 -DPICO_BOARD=adafruit_fruit_jam -DMODEL_BIN=$PWD/checkpoints/m3_decD_deep_full/model.bin

cmake --build build/fruitjam -j4

When the build is complete, the firmware file will be output as build/fruitjam/pico_faces.uf2. That file is ready to be copied to the RP2350 bootloader drive of the Fruit Jam.