Hi
Here is my problem. I have a 7.5" eink panel with the Xiao ESP32-C3 module in it. While looking for a firmware for it so I could use it easily with Home-Assistant, I made the mistake to flash it with a firmware for an ESP32-S3 
Now I’m unable to flash it back, in the flashing tool the serial port appears, then disappears then comes back all the time 
Even ESPConnect can’t connect to it anymore.
I tried also to reflash by holding first the button on the board but not better Did I kill it ?
I have tried to reflash it or check chip on it using ESPTool but it’s unable to communicate ! I have plugged the USB port while holding the Boot button on the Xiao but not better
Thanks
Hi there,
SO , welcome to level TWO 
Having boot looped a fair share..I can say if the (B) boot button is GPIO9 and SO is Pin9 so attach a wire fromPIN9 (GPIO9)_ to GND and try again hold it for the Whole 60 seconds…
Once it makes it to Boot-Loader mode,
perform a complete flash erase, FIRST!
It is normal When bad firmware is installed, the ESP32-C3 immediately enters a continuous crash/reboot loop, which causes the USB serial port to repeatedly connect and disconnect.
The ESP32-C3 has an immutable ROM bootloader baked directly into the silicon chip itself. Flashing incorrect firmware (like ESP32-S3 code) only overwrites the external flash memory—it cannot corrupt or overwrite the internal ROM bootloader.
Full Flash Erase via esptool: Once in hardware bootloader mode, the port will remain stable and won’t crash. Run the following command in terminal/command prompt to wipe the corrupted flash:
esptool.py --chip esp32c3 --port PORT erase_flash
Give it another go, You can’t break anything. 
HTH
GL 
PJ
Hi @PJ_Glasso
Thanks a lot for your help and the recovery process. If I understand well I hold the Boot button (it puts GPIO9 to GND according at layout of the module) while plugging power and hold at least 60s more the boot button and then I should be able to do the erase_flash with esptool right ?
If so it doesn’t work, esptool is able to open the serial port and then I get a Write timeout after 30s
Did I miss something ?
Hi there,
No , it’s not you … LOL it is the harware , Try to tap the reset button before you click FLASH, see if you can catch the timing right to get the bootloader hook to see or be seen by the Flasher,. 
It’s tricky and takes a few try’s
HTH
GL PJ
Once the com port sticks(it may change too) then the flash should work. 
Thanks for help and it’s all good now, it’s working back again Now back at initial problem: find a way to use these panels in an easy way and it looks like it’s impossible !
So far have tried OpenDisplay but it’s useless as out of displaying a picture it does nothing else, tried Tesserae but useless too as you can’t use any datas from HA, tried ESPHome Builder but buggy and not usable…