A Matter garage door lock

What are we trying to do

So, what problem is this project going to solve? Automating a garage door is a popular project for many electronics hobbyists. It's a manageable sized project, and to be hoest it's pretty cool.

Matter is a great new home automation protocol, and the number of device types it supports is growing - although frustratingly slowly. The latest version 1.2 of the Matter standard has added a few more devices. Some of these - such as refrigerators - seem an odd things to make it too the top of the queue. There's very little automation to be done with a fridge. You turn it on and just leave it on!

I was hoping that garage doors (or maybe just any automated door/gate) would pop up in 1.2, but it seems that's not the case. Well, let's see if we can do something about that. I already have some automation on my garage doors. The can be opened with a PIN or an implanted NFC tag. One thing I can do, however is control the door from my Google Home and more importantly, I can't tell if the door has been left open.

Starting with the existing Matter lock device

Nordic very helpfully have some sample code to let you create a Matter enabled device using their development kits. One of these is a lock example.