Arduino WeatherShield

Description: Communicate with Arduino WeatherShield by

Type: - Categories:

Development status:

Tested on: All platforms

Developer: Mauro Cicolella


The WeatherShield, created by [](, is a unit that lets Arduino able to read Pressure, Temperature and Relative Humidity. The shield is equipped with three sensors and a PIC12F683 microcontroller programmed with a specific firmware that interfaces with Arduino through a two line bidirectional synchronous serial connection. The microcontroller is responsible for sampling and averaging the last 8 humidity, pressure and temperature values, providing it to the Arduino in an ASCII readable format expressed in Celsius, hPa and relative % units. More details can be found [here](

Arduino WeatherShield

Arduino WeatherShield

Board protocol

The proposed solution uses an ethernet shield to connect Arduino board to your lan. On Arduino you must upload the included sketch to interact with the WeatherShield to retrieve sensors values and shows them as a string with ”:” char as delimiter. Also you must add to your Arduino IDE the WeatherShield lib (included into PLUGIN_ROOT/resources/WeatherShield/WeatherShieldLibrary).

The default address is on port 80. If you desire to change it you must edit the sketch, recompile and upload to Arduino board. To verify if it works open your browser and digit the board address “”. You would see a string reporting the sensors values.

How to read values from an object

With this board you can read the temperature behavior of any thermometer device in your environment.

For this example we use a thermometer object:

  • Right click on the thermometer object in the environment to show its configuration panel
  • Change the property “protocol” to “ArduinoWeatherShield”
  • Change the property “address” to a string composed of HTTP_BOARD_URL:HTTP_PORT. For example “” identifies the board listening on for temperature values (use “P” for pressure and “H” for humidity).
  • Under “temperature” (in Data Source Configuration) select the trigger called “Arduino WeatherShield reads temperature change”

The plugin is also able to read any humidity and pressure change.

From 5.6 version Freedomotic uses autodiscovering feature so 3 new things (thermometer, barometer and hygrometer) are added and configured automatically.

Source code

GitHub repository