There’s five steps to this:
- Install Mosquitto MQTT broker.
- Install zigbee2mqtt on your Pi. Follow the instructions from zigbee2mqtt.
- Pair your Zigbee device with zigbee2mqtt - find your device in this list and follow the instructions.
- Connect openHAB to Mosquitto
- Create a Generic MQTT Thing and configure it with the information for your Zigbee device.
Steps 1 & 4 are described here.
Step 5 depends on your Zigbee device. An example for a bulb is here.
Note that this assumes that your cc2531 already has the correct firmware, as per
If not, you will have to flash it using these instructions.