The cap off an addidas deoderant can makes a nice enough base for the orb from a B&Q disco lamp (no link as can’t find it online).  I soldered the ends of some CAT5 to the BlinkM, and left the other ends loose to be shoved into the arduino.

As I’ve got an arduino and ethernet shield, I went for the second largest ABS box and even then, I had to break off the screw connectors on one side so that the plugs could stick through the outside.  I soldered the AM receiver and transmitter onto a small piece of stripboard (also from bitsbox), added a couple of wires for aerials (with a knot in each to prevent someone pulling it out the circuit).  So that’s pretty much the finished product, what a shame!  I will add a thermometer to it so it can become a thermostat in another room – eventually this’ll go in the sitting room, so will have the current cost meter producing one temperature reading from the kitchen, this one in the sitting room, and have just ordered another arduino for my bedroom’s ambient light/thermometer/development board.

The java code has been working nicely, turning the heating on and off via the hacked home-easy plug!  I sent a text from my phone to turn the heating on, very proud of actually finding a use for it as I was stuck in traffic but had friends coming round so the heating would have cut out at 5.30 (it heats up til 5.30, then waits for movement) – only to find there was a street power cut that has lasted 3 days (intermittently)!  So, if the power holds up a little longer, I should get a tweet tomorrow telling me how long the central heating was on for, fingers crossed!

So, time to write the web interface, pretty dull

Adapted from Jibble, I have been recording data in “RRD”, a round-robin database in a single file.  Initially, I didn’t have a computer on 24×7, so added some cheap and tacky code to pull the historical data from the current cost meter and log that.  A couple of weeks after buying the current cost, I realised I couldn’t live without live readings, so bought the Viglen MPC-L.

View code.

Part of that code runs “colours.pl” with the current power consumption, which sends a message to the arduino telling it to change the ambient light’s colour to a colour that depends on how much power the house is eating up. More about that shortly.