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+# Reading a SONOFF SNZB-02P on a Raspberry Pi 5
+
+The simplest setup is:
+
+```text
+SONOFF sensor -> Zigbee USB dongle -> Zigbee2MQTT -> MQTT -> terminal/application
+```
+
+You do not need to open the sensor until Zigbee2MQTT is ready.
+
+## 1. Connect and identify the dongle
+
+Attach the dongle's antenna before powering it. Connect it to the Raspberry Pi,
+preferably through a short USB extension cable to reduce USB 3 radio
+interference.
+
+Run:
+
+```bash
+lsusb
+ls -l /dev/serial/by-id/
+```
+
+You should see a persistent device path similar to:
+
+```text
+/dev/serial/by-id/usb-ITead_Sonoff_Zigbee_3.0_USB_Dongle_Plus_...
+```
+
+Use this `/dev/serial/by-id/...` path instead of `/dev/ttyUSB0` or
+`/dev/ttyACM0`, because those shorter names can change after a reboot.
+
+Check the label on the dongle to determine its adapter type:
+
+| Dongle model | Zigbee2MQTT adapter type |
+| --- | --- |
+| `ZBDongle-P` | `zstack` |
+| `ZBDongle-E` | `ember` |
+
+The two dongles have similar names but contain different radio chips.
+
+References:
+
+- [Zigbee2MQTT adapter configuration](https://www.zigbee2mqtt.io/guide/configuration/adapter-settings.html)
+- [ZBDongle-P documentation](https://www.zigbee2mqtt.io/guide/adapters/zstack.html)
+- [ZBDongle-E documentation](https://www.zigbee2mqtt.io/guide/adapters/emberznet.html)
+
+## 2. Install the Mosquitto MQTT broker
+
+On Raspberry Pi OS, run:
+
+```bash
+sudo apt update
+sudo apt install -y mosquitto mosquitto-clients
+sudo systemctl enable --now mosquitto
+systemctl status mosquitto --no-pager
+```
+
+For an initial setup confined to the Pi and a trusted LAN, the local broker is
+sufficient. Configure authentication before exposing MQTT outside your trusted
+network.
+
+Reference: [Mosquitto downloads](https://mosquitto.org/download/)
+
+## 3. Run Zigbee2MQTT with Docker
+
+Zigbee2MQTT recommends Docker because it avoids most Node.js and dependency
+setup problems. Its image supports the Raspberry Pi's ARM architecture.
+
+If Docker and Docker Compose are already installed, create a working directory:
+
+```bash
+mkdir -p "$HOME/zigbee2mqtt/data"
+cd "$HOME/zigbee2mqtt"
+```
+
+Create a file named `compose.yaml` containing:
+
+```yaml
+services:
+  zigbee2mqtt:
+    container_name: zigbee2mqtt
+    image: ghcr.io/koenkk/zigbee2mqtt:latest
+    restart: unless-stopped
+    ports:
+      - "8080:8080"
+    volumes:
+      - ./data:/app/data
+      - /run/udev:/run/udev:ro
+    devices:
+      - /dev/serial/by-id/REPLACE_WITH_YOUR_DONGLE:/dev/ttyACM0
+    environment:
+      - TZ=Europe/Amsterdam
+```
+
+Replace `REPLACE_WITH_YOUR_DONGLE` with the exact filename returned by:
+
+```bash
+ls /dev/serial/by-id/
+```
+
+Start Zigbee2MQTT and follow its logs:
+
+```bash
+docker compose up -d
+docker compose logs -f zigbee2mqtt
+```
+
+From another computer, open:
+
+```text
+http://RASPBERRY_PI_IP:8080
+```
+
+For example:
+
+```text
+http://192.168.1.50:8080
+```
+
+The first-run onboarding page should appear. Configure these values:
+
+```text
+MQTT server: mqtt://172.17.0.1
+Serial port: /dev/ttyACM0
+
+Adapter:
+  ZBDongle-P -> zstack
+  ZBDongle-E -> ember
+```
+
+If `172.17.0.1` does not reach Mosquitto, use the Raspberry Pi's LAN IP
+instead. Zigbee2MQTT may detect the adapter automatically.
+
+References:
+
+- [Official Zigbee2MQTT Docker installation](https://www.zigbee2mqtt.io/guide/installation/02_docker.html)
+- [Zigbee2MQTT onboarding](https://www.zigbee2mqtt.io/guide/getting-started/)
+
+## 4. Pair the SNZB-02P sensor
+
+In the Zigbee2MQTT web interface:
+
+1. Click **Permit join**.
+2. Open the SNZB-02P.
+3. Remove the battery insulation tab.
+4. Hold its button for about five seconds, until the LED flashes.
+5. Keep the sensor close to the dongle during pairing.
+6. Wait for Zigbee2MQTT to report that the device was successfully interviewed.
+7. Rename it to something simple, such as `living_room_sensor`.
+8. Turn **Permit join** off afterward.
+
+The device page should now show temperature, humidity, and battery level. The
+SNZB-02P uses a CR2477 battery.
+
+Reference: [SNZB-02P device support](https://www.zigbee2mqtt.io/devices/SNZB-02P.html)
+
+## 5. Read the temperature
+
+Listen for sensor updates on the Raspberry Pi:
+
+```bash
+mosquitto_sub -h localhost \
+  -t 'zigbee2mqtt/living_room_sensor' \
+  -v
+```
+
+A message will look similar to:
+
+```json
+{
+  "battery": 100,
+  "humidity": 48.2,
+  "linkquality": 132,
+  "temperature": 21.6
+}
+```
+
+To print only the temperature, install `jq` if necessary:
+
+```bash
+sudo apt install -y jq
+```
+
+Then run:
+
+```bash
+mosquitto_sub -h localhost \
+  -t 'zigbee2mqtt/living_room_sensor' |
+jq --unbuffered '.temperature'
+```
+
+Battery-powered sensors normally report periodically or when their readings
+change, rather than continuously. The SNZB-02P publishes `temperature` in °C
+and `humidity` as a percentage.
+
+Reference: [Zigbee2MQTT MQTT topics](https://www.zigbee2mqtt.io/guide/usage/mqtt_topics_and_messages.html)
+