This articles describes how you can use I2C (TWI) communication, Arduino and temperature sensors to measure 3 different temperatures. It can be very ...

The controlling chip — an Arduino, in this case — can read the intensity of the selected color. The TCS230 uses a 4 x 4 array of photodiodes, along with a Bayer filter.

[Fjord Carver] brings together an RGB LED and CdS Photoresistor to make a color sensor. Those Cadmium Sulfide lights sensors usually have a very wide swing of resistance when exposed to varying lev… ...