I am trying to set up JLink debugging on an Adafruit ItsyBitsy M0 Express (SAMD21). I have my JLink connected to the baord and I am able to flash a sketch and start debugging. The issue is that whenever a debug session is active, the Serial port from the board does not appear and this causes the ske…

The bootloader is just an additional program loaded into the first section of flash. You can reflash it any time since the bootloader binary is available , so absolutely no non-reversible thing is done to the board.

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Debugging issue - ItsyBitsy M0 Express - JLink

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maxgerhardt December 13, 2022, 6:22pm 4

Have you tried removing the bootloader? (like this)