I have an older Sonoff 4 Channel Relay (R2 Pro) which I had flashed with Tasmota firmware version 6.4.1.
In the interest of incorporating easily into my home automation I decided to upgrade the Tasmota firmware to the latest version (9.5.0 at the time of this writing). I want to use it for landscape lighting.
I uploaded the Tasmota minimal which did upload but when the relay rebooted the relay 2 light came on and the relay 1 relay began furiously clicking.
The WiFi was NOT connected as well. No problem. I’ll just put the device in boatloader mode and rewrite the flash memory. You do that by holding down this button while powering up:
Enter boot loader mode (click pic to enlarge)
Great, except it didn’t work. I was pretty sure it was bricked for all eternity and I was ready to throw it in the trash. Holding the button down is supposed to short data pin GPIO0 (zero) to ground causing the device to enter boot loader mode.
I decided I would try to manually short GPIO0 to ground by using these pins while the FTDI controller was connected.
Shorting GPIO0 test point to GND manually WORKS!
Shorting Manually GPIO0 to GND (click to enlarge pic)
The Sonoff booted with no relay chatter and I was able to program Tasmota latest with ESP-Flasher on Mac with no issues. Once configured as Sonoff 4CH Pro it looks like this.
Charlie Sheen style winning!