I have a load of smart devices in my house that all have ESP8266 microcontrollers inside them. They all work with the Tuya SmartLife app on my phone, and the Tuya integration in HomeAssistant. They also all talk to China to do anything. I’d rather they didn’t. China doesn’t need to know I want to turn my lighting on.
There used to be a way to do this over the air, faking a proper firmware update but that doesn’t seem to work any more. Tuya has got wise to this trick and devices now come with firmware that doesn’t let this happen. So what we have to do is get inside the device and find the little WiFi module with the ESP8266 on it. Then we can reprogram it with Tasmota. Tuya have also got wise to this and newer devices come with WiFi modules using other chips now. That’s the point we go off and buy Sonoff devices instead.
Oh this is not a howto, just go to the Tasmota website and start reading. You might need a soldering iron, you might need a dremel.
This was a fun little project where at first I had no idea what I was doing, just blindly following instructions and hoping for the best. Your bog standard Sonoff switch is easy to hack, the programming pins are right there on the board waiting for you.
Other devices are a bit more tricky. Getting inside them is the hard part to begin with.
Then you have to find the module’s pins which can also require a bit of disassembly.
And then you have to work out which pins are needed, and they’re never labelled because remember – we’re not supposed to be doing this. And sometimes the button on the side isn’t the ESP8266’s reset button, it’s just some random GPIO so then you need to also find the reset button.
I have a bunch more of these things in my house to hack later. I’m not sure I want to do the light switches though, I use voice control to also make those work and I don’t know how to make HomeAssistant understand voice commands from Google Assistant.