Example OOT project for Dev Board Micro

This is a "Hello World" out-of-tree project for the Coral Dev Board Micro.

This serves as a starting point for your own Dev Board Micro projects when you want your project to live outside the coralmicro tree, rather than inside it. For more information about creating a project, either in-tree or out-of-tree, see the guide to Build apps with FreeRTOS for the Dev Board Micro.

Note: This project depends on coralmicro, which requires about 2.5 GB.

1. Clone this project and submodules

git clone --recurse-submodules -j8 https://github.com/google-coral/coralmicro-out-of-tree-sample

2. Build the project

cd coralmicro-out-of-tree-sample

cmake -B out -S .

make -C out -j8

To maximize your CPU usage, replace -j8 with either -j$(nproc) on Linux or -j$(sysctl -n hw.ncpu) on Mac.

3. Flash it to your board

python3 coralmicro/scripts/flashtool.py --build_dir out --elf_path out/coralmicro-app

Anytime you make changes to the code, rebuild it with the make command and flash it again.

Note: In addition to specifying the path to your project's ELF file with elf_path, it's necessary to specify the build output directory with build_dir because flashtool needs to get the elf_loader (bootloader) program from there.

If you followed the guide to get started with the Dev Board Micro, then both the build_dir and elf_path arguments are probably new to you. That's because when flashing in-tree examples and apps (as we do in that guide), the build_dir is ommitted because the flashtool uses the local build directory by default. Similarly, in-tree examples and apps don't need to specify the ELF file with elf_path because those files are built in the same build directory—we can instead specify just the project name with --example (or -e) and --app (or -a) when flashing these in-tree projects.