BSD29 Smart Socket (ESP8285) - Custom Firmware

Recently, I found out that ESP8266/8285 based IOT devices could be flashed with custom firmwares. The benefit of doing this is having the ability to use local servers instead of the servers that came provided with your device like Tuya/Smart Life.

However, newer devices have been updated and cannot be flashed using an OTA method like Tuya-Convert due to an update in the PSK used. You can read more about the issue here. The only way to flash newer devices as for today (8 July 2020) is to flash them physically.

The BSD29 can be opened by prying the edges of the bottom of the plug. Take your time during this step to prevent any cosmetic damage as the two halves has been glued or ultrasonic welded together.

The BSD29 is equipped with a ESP8285 (AJW-02_8285) and it has to be de-soldered from the main board in order for it to be flashed with a custom firmware. The area marked in yellow are the solder points that has to be removed.

These are the necessary pins required for flashing:

  • Red: 3.3v
  • Green: Ground
  • Blue: RX
  • Yellow: TX
  • Pink: GPIO 0

Check out Tasmota guide for more details on flashing.