Recently I ordered an AVR microcontroller based ethernet device and some sensors from Tuxgraphics*. It’s a controller board with an atmega328p processor and ENC28J60 ethernet controller onboard. You can connect any number of sensors and switches to the processor, so I ordered some to get started: two temperature sensors (IC2 protocol), one air pressure, one humidity and temperature. That’s just about enough to make a weather station!
Today I got around to soldering it together and trying it out.
The big surprise: it worked first try: no soldering errors, and the programming worked too: a network enabled thermometer! A little bit more hacking and I got a second thermometer mounted (in a broken pen body filled with silicon to waterproof it) outside my window.
And now the best part – a few quick scripts, and voila: here you have the current (updated every 5 minutes) temperature data for my house! Please note – the indoor temperature shown is about 2-3 degrees warmer than it really is in the room because the sensor is near my computer…
Sat Oct 2 16:00:01 2010 DS18S20 Sensor Indoors = 15.0C DS18S20 Sensor Outdors = 12.8C STH11 Sensor Indoors temperature = 20.4C STH11 Sensor Indoors dew point = 14.2C STH11 Sensor Indoors humidity = 71.0%
(or click here for the text file – F5 to update)
Pretty neat eh? Now I just have to get all the other sensors working, and build something to measure wind and rainfall…
Related links
- Tuxgraphics.org
- Mikrocontroller.net (German site about programming micro controllers)
* If you order from Tuxgraphics, beware that they send from Canada, meaning that you may have to go to the customs to clear it. In Munich, going to the Customs takes an hour each way, and is a big hassle… The alternative is to have it sent by TNT (they will handle the customs for you), but that costs a lot extra…
