A client/server architecture for communication between a microcontroller and an OPC-UA server.
The OPC-UA server acts as a client that polls the arduino for its state, or requests it to perform an action (In this example, turning on and off a LED).
Use Arduino IDE to compile and upload server/server.ino to the controller.
python -m venv venv
./venv/Scripts/activate
pip install -r requirements.txt
python client/opcua.py
This example uses opcua-asyncio and PySerial.