The project demonstrates a Raspberry Pi acting as a Bluetooth Low Energy (BLE) Peripheral that allows reading/writing a single data value, and an Arduino client which periodically connects and writes data.
Install the dbus library via
sudo apt install build-essential libdbus-glib-1-dev libgirepository1.0-dev
pip install dbus-python
Install the ArduinoBLE package.
The Arduino scans for a specific device address which you'll need to get from the Pi with the command echo -e 'show\nquit' | sudo bluetoothctl which should produce output that looks like:
Controller XX:XX:XX:XX:XX:XX (public)
Name: raspberrypi
Alias: LighthouseWeatherStation
...
The string that looks like XX:XX:XX:XX:XX:XX is what you want - copy that and paste it into the #define PERIPHERAL_ADDR "XX:XX:XX:XX:XX:XX" line in the arduino code.
Start the service on the Pi via sudo python3 main.py which should output:
GATT application running
GATT application registered
GATT advertisement registered
When the Arduino is running you should see lines like Value received: 309 every second as the Ardunio sends data to the Pi via BLE!
The Raspberry Pi portion of this project is basically a stripped down version of this Lighthouse Weather Station project.