I put in an order to Little Bird Electronics at Christmas to take advantage of a 10% discount coupon, so I added a few bits and pieces that might come in handy. First off was a DHT22 temperature and humidity sensor, which is readily available with lots of examples around. First I tested it with some sample code, and then modified my existing ‘weather’ station code. So now I have two different measures of light levels, two temperature readings and humidity. There is a slight difference of about half a degree between the two temperature sensors, so I wonder which one is more accurate? The Xively feed immediately picked up the two new data streams, and as a bonus my iPhone app also recognised them.
I also bought an MPL3115A2 barometer/altitude sensor which looks interesting, but it is my first experience of the I2C bus and it appears that to run long distances to an outside sensor it needs a bus driver of some sort, so this one is going to take more effort. The code looks rather daunting too.