Automating blinds and curtains

My parents have a number of blinds and curtains that open and close on timers. These are great, but maintaining their timers is a pain. Not only does sunrise and sunset change on a daily basis, but twice a year the country moves on or from daylight savings. and everything is suddenly out by an hour.

Silent Gliss curtains

They have curtain motors from a company called Silent Gliss and I was able to use a cheap setup combining a Raspberry Pi (3B) with a 433.92Mhz transmitter and receiver to first capture the codes transmitted from their remotes and then use a Python script triggered by timers in Domoticz to transmit them.

This had largley been working fine for a the past 10 months or so, with the odd hiccup regarding one curtain failing to respond every now and again, but generally it had been reliable.

Somfy blinds

They also have some blinds though, from a company called Somfy. And they use a a slightly different frequency (433.42Mhz) that required either hardware hacking the transmitter I had or some new ones.

I had originally found a library (Pi-Somfy) that claimed to work with the RTS protocol the blinds use via a cheap CC1101 transeiver module. I even found a company that sold them with a HAT to make attaching to the Pi easier.

Getting this working proved to be difficult. Possibly the wiring isn't correct (ChatGPT and I spent a lot of time trying things, I could get the modules to talk to each other but never to the blinds).

The RFXCOM 433EMC

I had been considering a different solution and then we seemed to be getting more dropouts from the curtains than usual (possibly just due to the placement of the Pi but still). So when I saw the RFXCOM units were back in stock I grabbed one.

It clearly stated it supported the Somfy RTS protocol so at least it could work the blinds and I was hoping I could raw capture the codes for the Silent Gliss curtains if nothing else.

The setup

It wasn't quite as straightforward as I'd hoped but here's the steps I had to take:

Flash the RFXCOM

It wasn't entirely clear but it appears the first thing you should do is flash the device when it arrives. To do this I had to connect it via USB to a Windows computer and wait for it to sort out the drivers to the web flash manager could find it and install the new firmware.

Somfy blind setup

While connected to the Windows machine I downloaded the RFXmgr software and connected it to the RFXCOM 433EMC. I was then able to follow the steps in the manual to pick the type and set a hardware ID and unit code. I then put the blind into program mode and transmitted the program signal (select the signal type from the dropdown).

That immediately connected the two and I could double check by sending the Up/Down signals and see it was moving.

I could then save those settings and disconnect it.

Raspberry Pi/Domoticz setup

Connecting the RFXCOM unit to the Pi via USB I was then able to confirm I could see it by running lsusb in the terminal (mine showed as ttyUSB0).

I could then go to Setup > Hardware in Domoticz and select the RFXCOM unit with the correct frequency and add it. I could then manually add a switch with the type of RFY and the same ID and unit code as I'd used earlier. And voila control of the blind.

Silent Gliss curtains setup

It turns out that the curtains used the A-OK AC114 protocol, which the RFXCOM has under Blinds T1/T2/T3/T4.

To enable this protocol on the unit you can either do it in RFXmgr or via Domotocz by going to Setup > Hardware. Once there click the Set Mode link below the device name in the Type column. On that screen tick the box for the protocol and then click Set Mode and wait until the page redirects.

Now go back to the Switches tag and click the Add Light/Switch button, click the open or close button for the curtain and it should capture it. Add a name and you're good to go.

Setup the timers

Now add your open/close timers as appropriate.

Hopefully that'll help someome (even if it's just me) trying to do something similar.