Flash Fan Controller The Hard Way

One of the challenges we are faced with when it comes to flashing Tasmota on a Tuya device is that Tuya has now closed the exploit that TuyaConvert was using to change the firmware. Therefore we need to physically access the Wifi module on the device and flash the firmware using the serial interface.

Fortunately for us, Tuya has made this process a lot easier, they publish data sheets on most if not all of there wifi modules utilised, so to that end, we first must disassemble the controller so we can see what model controller it is using.

So what we need to do is solder some jumper wires to pins on the wifi module, it is essential that you DONT DO THIS WITH THE UNIT PLUGGED INTO MAINS POWER!!!

As I have explained in my other tutorial, for this part of the project, we need to use a soldering iron, we also need to use some Dupont hookup wires. Rather than repeat myself, I recommend you review that tutorial and then come back to this section, the process in both tutorials is very similar from this point forward. you can find the tutorial here the main difference is in this case we are not going to remove the module from the device, we can flash the new firmware with the module in place.

So to recap the steps that we followed in the other tutorial are as follows:

• Solder Dupont hookup wires to the pins described above

• Connect the pins as follows to the USB to TTL UART RS232 Serial (PL2303)

  • U1TX - this will be connected to the RX pin of the USB interface we will use to upload the firmware

  • U1RX - this will be connected to the TX pin of the USB interface we will use to upload the firmware

  • 3v3 - this is where you can connect the DC volts to power the Wifi Module

  • GND - This is where you can connect the DC ground to power the Wifi Module

  • IO0 - this will need to be held low at boot to put the module into boot loader mode.

  • Use a breadboard matrix to make the process easier grounding IO0 to ground easier.

• With the wifi module is connected to the PL2303 we boot it while holding the IO0 pin to ground. Then using Tasmatizer, we connect to the PL2303 com port and follow the same process as described in my previous tutorial. All going well your device should now have Tasmota running on it.

• After the device has booted up, use the send config option to send the Wifi settings and the template to the device, once the device is successfully connected to your Wifi network, you can set the device up using the same process as described here using the same template and backlog commands.

• Lastly, remove the hookup wire and reassemble the device and install.

Have fun.