Posted on Sep 24, 2012 in Thermostat | 0 comments

The Raspberry Pi is probably the best thing to happen since the Arduino in terms of low cost systems that don’t requite an engineering degree to get started with. At $35 it is tremendously powerful and like the Arduino, has a great community working on a bazillion projects, almost all of which are open source.

Although the Pi was mainly intended to make programming and computing accessible to younger children all over the world (remember OLPC?), with its inclusion of its General Purpose Input/Output (GPIO) connectors, it makes for every hardware hackers’ wet dream. The little pins allow the RPi too be able to communicate digitally to all sorts of components: LEDs, sensors, relays, etc.

On the Pi’s initial release, GPIO support was kinda-sorta-there. Few months in and its as easy as Pi. (Hah see what I did there? =) ) The board runs Linux and there are several great distributions around, but for anyone experimenting with the GPIO, I would very highly recommend going with Adafruit’s Occidentalis. With a bit of python code that comes baked in, you’re ready to start plugging in all sorts of components in a matter of minutes.

Since my thermostat at home sucks, I’ve been playing around with making one out of a Pi. There are essentially 3 steps to this.

  1. Have the Pi detect the temperature. (Input)
  2. Know when to turn the fan, heater or ac ON or OFF (Logic)
  3. Turn on the right switches (Control)

Sounds simple enough. Time to get to work!