So, building on what I did before with lights and switches as well as the stuff I’ve been hacking together with my Home.API, I thought I’d build something that may actually be of practical use. So, here’s a device that will tell you, before you walk out the door, whether all your doors and windows are shut, and for bonus points, tell you when they were opened and closed.

As you can see from the video, my local Homebase didn’t have all the bits, so you’ll have to use your imagination a little. The “Real” version would use simple magnet + reed switch burglar alarm fittings connected with bell wire to the terminals on your Piface. An indicator panel connected on the PiFace’s output panel should sit somewhere visible by your front door.

The software, again written in python, is very simple. It loops through all 8 input connectors and turns on or off the corresponding light when it reads a switch open and closed, when it detects a change it writes some output to the terminal and writes a message to the system auth log. This last feature is made even more useful if you configure the Raspberry pi to send its logs to a central server, as I have previously written about.

The next obvious thing to do is to interface this system with the Home API, which would be straight forward to implement (and I will implement when I get a moment!)

Here’s the circuit:

Click on the circuit to see a larger image…

…and here’s the code:

Enjoy!