openHASP/docs/16-compiling.md

Cloning

Make sure to add the --recursive parameter when cloning the project from GitHub. Otherwise git will not download the required submodules in the /lib subdirectory.

git clone --recursive https://github.com/fvanroie/hasp-lvgl

If you already cloned hasp-lvgl without the submodules, you can fetch the submodules seperately using:

git submodule update --init --recursive

To switch to a different branch use:

git clone --recursive https://github.com/fvanroie/hasp-lvgl
cd hasp-lvgl
git checkout 0.2.0
git submodule update --init --recursive