Internet-of-things does not require that every device has to be directly connected to the Internet. The complexity and possible security issues with every sensor having its own IP address would in fact be overwhelming. A better approach would be to use more light-weight protocols for the sensor and actuator data and locally aggregate and filter these data at common points before making them available on the Internet. In this post I will describe a theory and implementation of transmitting small radio chirp messages from an Arduino Pro mini and then receive these data on a Raspberry Pi for transformation to MQTT messages for the Internet.
In this post I will connect a Processing sketch with an Arduino for the purpose of visualizing the input and output pins of the hardware board with graphics in Processing.