The fridge temperature sensors and switches are from the 1-wire family of components. I’ve kept all of those parts from version 1 – you can read about it here.
For the PC this time I chose a Windows 7 tablet (edit: now running Win 8) imported from China. It might seem like an odd choice, but for this project it was a really good fit.
I wanted a decent (capacitive) touch screen, but for the moment at least 10-12 inch monitors are quite expensive and a 23 inch monitor would be excessively large.
I considered the arduino for the processing platform, but they aren’t quite powerful enough for what I was hoping to achieve. The Rasberry-Pi looks impressive for the price, but I would have still bee waiting for it, and I’d still need the monitor.
While researching my monitor options I stumbled upon these Intel Atom based tablets made by ODMs. It’s effectively a previous generation netbook without a keyboard. Dual core Atom N570, 1.6 GHz, 2 GB RAM, 32 GB SSD, Wifi and bluetooth for around $400 delivered (it arrived in 4 days) + another 32 GB microSD for $30. I can’t recommend it as a tablet computer – the battery lasts around 2.5 hours, the screen has an ordinary viewing angle and the fan runs almost constantly when the screen is on. But it’s great as an always on, and low power server with a touch screen. And it doubles as a media streaming box when I’m outside or in the garage.
I built a little stand for it out of timber and dowel and painted it black. Behind the tablet I left room to mount the 1-wire control box, creating a neat little unit.