This tutorial demonstrates how to use the Arduino to read in analog inputs and update a ThingSpeak Channel by sending an HTTP POST via the Arduino Ethernet Shield or the Arduino Ethernet (all-in-one). The analog input can be the output of a sensor, like a light sensor or temperature sensor. In addition to sensor data logging, this sketch updates a Twitter status every hour via ThingTweet.
ThingSpeak Channel and Twitter Updater Sketch
This Arduino sketch takes the value of Analog Pin 0 and Analog Pin 1 and updates Field 1 and Field 2 of a ThingSpeak Channel using the ThingSpeak API. It also updates a Twitter status every hour with the latest sensor value via ThingTweet.