Ever since moving into my first very own home I’ve been wanting to start working with home automation. I didn’t want to buy a off-the-shelf system (where’s the fun in that?) and googled around a bit for possible setups. The first piece of software I came across was Domotiga, which seemed to support most of the things I wanted to achieve. However Domotiga is written in a programming language I had never heard of before (gambas) so changing things to suit my needs was going to be a challenge. No matter, it had everything I wanted so I dusted of my old and broken (the screens gone) notebook and installed everything. My first impression was good, the software had a nice GUI and all the options where there. Onward with the building of things!
Now that I had selected the software, the first thing I wanted to be able to do was controlling the thermostat. While I was checking out Domotiga, I found it supported something called Opentherm Gateway, so I decided to go and build that with the help of my brother. After all the parts arrived I went over to his house and we put together the gateway, with some minor adjustments to the design (something about an extra short-circuiting protection or whatever). We then hooked it up to his thermostat and heater system and fired up the supplied utility and set a new Opentherm setpoint and it WORKED, Hooray! 🙂
With the working gateway in hand I headed home, eager to hook it up to the Domotiga system I had waiting.
Once home I hooked it up but nothing happened, the software didn’t find the gateway, the utility I had used at my brothers house didn’t find it either. So I went back to my brother and we tried it in the same setup as the first time… Nothing! Damn it. My brother got out his trusty diagnostic equipment and we found the one of the transistors was bad, so he replaced it and I took the gateway back home and tried again. This time the utility from the gateway’s website found it but Domotiga didn’t, did some debugging and opened a topic for support and found that there was a bug in the software so that it didn’t initialize the gateway correctly. Well, at least the gateway was working!
While waiting for a new version of Domotiga with a fix for the gateway I though about the next steps I wanted to do. The first thing that came to mind was that I wanted a low power solution, because it was going to be an always on system and that the system should be wall mounted next to the heater. The notebook Domotiga was installed on was not easily wall mountable and drew more power then I hoped. Then one day, when checking for a new version, I found out that some people also using Domotiga got it working on a Raspberry Pi.
Having heard a great deal about the R-Pi’s low powered nature I put 2 and 2 together and ordered 2 R-Pi’s (why 2? because at the same time I found OpenElec XMBC for R-Pi)
…And then I waited for the R-Pi’s to be delivered. Which I think is a nice place to conclude this first part of the projects history.
Read on in part 2
Resources for this article:
Domotiga available @ https://www.domotiga.nl/projects/domotiga/wiki/Home
OpenTherm Gateway @ http://otgw.tclcode.com/