My first attempt at home automation: Alexa-controlled Christmas tree lights!

I’ve wanted to play with some home automation tech for a while now but the absence of clear standards and relatively high cost of entry (with many of the popular systems requiring a hub) put me off. We also have the relatively unusual situation in that there is nearly always someone in our house, so even the idea of a smart thermostat to turn down the heating when we’re out (e.g. Nest, Hive, etc.) is not a good fit for our lifestyle.

Then, a few weeks ago, I bought myself an Amazon Echo Dot. My business case was weak. After all, voice controlling my Spotify playlists is a bit of a novelty (and not all of the “skills” that are available in the US are available over here in the UK) but I could see there was potential, especially once IFTTT support comes to the UK (which it finally did, last week).

Over the weekend, I decided to take things a little further and to see if I could control some lights. I wasn’t getting far with the fixed infrastructure in the house (due to challenges with a lack of a hub and B22 vs. E27 light fittings meaning I’ll need to convert some of the light pendants too…) but my colleague Richard Knight (@rmknight) suggested a TP-Link Smart Plug and I picked up a TP-Link HS110 on Amazon. Then it was a case of deciding which lights to control – and I went for the Christmas Tree lights…

After a fairly simple setup process (using TP-Link’s Kasa mobile app) I had the switch working from my phone but then I took things a step further… voice control with Alexa. Kasa and Alexa are integrated so after enabling the skill in Alexa and linking to Kasa, I was able to control the lights with my voice:

Everything I’ve described so far was just a few minutes’ effort – remarkable straightforward out-of-the-box stuff. Being a geek, I started to think what else I could use to control the Smart Plug and I found an excellent post from George Georgovassilis (@ggeorgovassilis) on controlling a TP-Link HS100 Wi-Fi Smart Plug. In the post, George sniffs the network to work out exactly how the smart plug is controlled and he provides a shell script, then others have chipped in with C# and Go options. I had to find which IP address my Smart Plug was using (looking at the DHCP server leases told me that, then a MAC address lookup confirmed that the unknown device starting 50:c7:bf was indeed a TP-Link one).  Using the compiled C# code I successfully controlled my HS110, switching the lights on/off from the command line on a PC.

So, last year saw a miniature Raspberry Pi-powered Christmas Tree (featuring my terrible soldering) – this year I’m controlling the full tree lights using mainstream components – I wonder what Christmas 2017 will bring! And my second Echo Dot is arriving today…

Somfy roller-shutter garage door stopping part way down

Last year, I replaced our up-and-over garage door with a roller-shutter version.  It wasn’t new; our neighbour converted her garage so I bought her nearly-new door but that means I didn’t have a professional installer to fall back on when it stopped working recently.

The garage door control system is a Somfy Rollixo RTS and last week, we found that the door would come part way down and then stop, as though there was an obstruction. After winding it down manually one morning, Mrs W was not happy and I promised to take a look when I got home. I couldn’t find the problem – what’s more I couldn’t troubleshoot it using the manual either.  What I did notice though was that, rather than the two red lights I’d expect to see for a safety-edge transmitter low battery indication, I had one red light on the control box, and one orange light on the safety-edge transmitter (which is fitted to the door curtain).

Somfy Rollixo RTS instruction manual has incorrect diagnostics for low battery warning on safety-edge transmitter

I found I could over-ride the cut-out by pressing and holding the remote control button, and set off to the Internet to find a replacement 3.6V Lithium AA battery. First mistake was not reading the Google results carefully enough and ordering a 2/3 AA battery from Farnell/Element 14. Now I can’t return it as I can’t find a courier who works with consumers and will carry Lithium batteries! In the meantime, I’ve bought the correct (AA) battery and, this morning, I swapped it over, after which I found the door operated as it should. That was a relief, as I feared that swapping over the battery would wipe some settings and require me to re-programme the door.

So, why blog about something as trivial as changing some batteries? Well, because the instruction manual is wrong and my experience might help someone else!