Energenie MIHO109 - Converting to Tasmota

 

The MIHO109 smart plug is different from most Energenie devices because it communicates directly with their cloud service via WiFi. Although the Energenie service has an API, I wanted to see if I could integrate these plugs directly with Home Assistant. I took one apart to take a look...

I found they come apart easily as there's no glue or clips to pry apart, just 3 T8 safety screws. Inside there's an ESP8285 on a separate module (essentially an ESP8266 but with the flash memory included). I traced the pads to the various pins on the ESP chip and luckily the RX/TX pins are exposed the edge connector.

By temporarily soldering some jumper wires to the RX/TX/3.3v/GND pins it's not necessary to remove the module to flash new firmware. I use a FT232 USB to TTL adapter for this as it also supplies 3.3v to the ESP chip (higher voltages can kill it). I use Tasmotizer as the flashing tool as it has a Windows GUI interface.

 

Once the new firmware has been flashed and the plug reassembled, setup is just like any other Tasmota device.

Template:

{"NAME":"MIHO109","GPIO":[32,1,1,1,1,1,288,224,1,1,1,1,1,1],"FLAG":0,"BASE":18}

⚠ Safety warning

These plugs operate at mains voltage and there are exposed terminals inside. If are are unsure of the necessary safety precautions then do not attempt this. Never attempt to flash the ESP chip when it's connected to the mains.