Upload different bootloader into XIAO

Hi, The current bootloader that comes with XIAO is unreliable. It randomly stops working when trying to upload from arduino IDE. I love XIAO for its very small size and cost. Its a great product, except for this bootloader issue.
Anybodys knows if we can replace the current bootloader with a different stable one, like the bootloader used in arduino (optiboot) or adafruit M0 or something like that? A robust and reliable bootloader will make XIAO an awesome product.

Hi @John_Doe
You can have a try CircuitPython Bootloader for Seeeduino XIAO .
More info refers to here.

Hi, I’ve found another solution with someone’s help actually. I had an issue that I couldn’t upload anything at some point and port has changed from COM6 to COM7 and it looked like in bootloader mode.
The fix was to manually change COM7 to COM6 in Device Manager (right-click on the port, go to Properties->Port Settings->Advanced and then force change port). After that I reconnected XIAO and uploaded blank script with start and loop only. And it worked! :slight_smile: Now I can do everything fine as previously.

@John_Doe any luck finding a new bootloader for the Xiao?

It seems that more and more people are running into the same problem: A bricked Xiao…

Unfortunately it seems that @Seeed does nothing whatsoever to solve the problem. In my humble opinion they have an obligation to do so, as we paid for a working product, not a brick…


If you have a spare ESP32 board, you could flash a VCON firmware on it which turns ESP32 into a remotely controlled programmer. Wire ESP32 to the XIAO’s SWD pins, and reflash XIAO - you could reflash any bootloader on it, or Arduino-compiled sketches.

If you’re uploading a bootloader, make sure it is in .hex format.

Wiring instructions are at https://vcon.io/docs/#seeeduino-xiao
ESP32 flashing instructions are at https://vcon.io/docs/#generic-esp32

If you keep ESP32 wired to XIAO, you could reflash your XIAO remotely at any time.

Disclaimer - I do represent VCON product. It is commercial, with freebie quota for first 10 devices, so reflashing XIAOs (and not just XIAOs) could be done absolutely for free.