This is a great project for those just starting out with their Raspberry Pi or who don’t feel totally comfortable soldering yet. Via The MagPi
With the help of some exciting code and some clever electronics, you can use your Raspberry Pi to read an analogue signal from a photoresistor without the need for a conversion chip! Armed with this power, you can measure the ambient light level and trigger an effective alarm. The project is designed as an extension to the projects found in the Monk Makes Raspberry Pi Electronics Starter Kit.
See the full tutorial here.
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