What you need

• A USB cable
• Firmware download utility esptool.exe (Windows): download
• The firmware file: sensornode_factory.bin

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Step 1 — Unpack the firmware download utility

Download the firmware download utility, save, unpack to the known place on disk. Open Windows command prompt, terminal or powershell from that place.

Step 2 — Flash the firmware

Connect the device by USB, press and hold BOOT button, then shortly press RESET button and release both.

then in the cmd window run:

esptool erase_flash

This command erases internal flash in the device. After it has finished, run:

esptool write_flash 0x0 sensornode_factory.bin

This command erases internal flash in the device. After it has finished, run:

Step 3 — Connect to the device

After it restarts, it creates its own WiFi network:

Network name	AirMQ-SN-<chipId>
Password	none

Connect to it with your phone or laptop. A setup page should open automatically — if not, open http://192.168.4.1 in a browser.

Step 4 — Join your WiFi network

In the WiFi Setup section:

1. Enter your WiFi network name and password
2. Click Save, then Reboot

The device will restart and connect to your network.

Step 5 — Check if it’s already set up

Reconnect to the device on your normal WiFi network (check your router, or the SensorNode web page if it’s still reachable). Give it a minute or two — if this device has been used before, it may configure its MQTT and sensor settings automatically, with nothing else to do.

If readings aren’t showing up after a few minutes, continue to Step 5.

Step 6 — Set up MQTT and sensors manually

Open the device’s web page and:

1. Go to MQTT Config and enter the broker address and port
2. Go to Sensors and add each sensor that’s connected, with its type and pin
3. Click Save, then Reboot