Have you tried Reset or Enter Bootloader Mode?
It is introduced in XIAO’s wiki document.
I’ll post it, and you can try to see if it can solve the problem. If it doesn’t work, tell us your problem again.
Enter Bootloader Mode ¶
Sometimes the Seeeduino XIAO port may disappear when user programming process fails. we can solve this problem by the following operation:
- Connect the Seeeduino XIAO to your computer.
- Use tweezers or short lines to short the RST pins in the diagram twice.
- The orange LED lights flicker on and light up.
At this point, the chip enters Bootloader mode and the burn port appears again. Because the samd21 chip has two partitions, one is the Bootloader and the other is the user program. The product will burn a bootloader code in the system memory when it leaves the factory. We can switch modes by performing the above steps.
Reset ¶
If you want to reset the Seeeduino XIAO, perform the following steps:
- Connect the Seeeduino XIAO to your computer.
- Use tweezers or short lines to short the RST pins only once
- The orange LED lights flicker on and light up.
Please note: The behavior of the built-in LED is reversed to the one on an Arduino. On the Seeeduino Xiao, the pin has to be pulled low, whereas on other micro-controllers it has to be pulled high.
