Adafruit ESP32-S3 - For SAMD21 non-Express boards that have a UF2 bootloader:

CLUE_Flash_Erase.UF2
Matrix_Portal_M4_(QSPI).UF2
 2. Double-click the reset button on the board to bring up the boardnameBOOT
drive.
 3. Drag the erase .uf2 file to theboardnameBOOT drive.
 4. The status LED will turn yellow or blue, indicating the erase has started.
 5. After approximately 15 seconds, the status LED will light up green. On the
NeoTrellis M4 this is the first NeoPixel on the grid
 6. Double-click the reset button on the board to bring up theboardnameBOOTd
rive.
 7. Drag the appropriate latest release of CircuitPython() .uf2 file to theboardnam
eBOOTdrive.
It should reboot automatically and you should see CIRCUITPY in your file explorer
again.
If the LED flashes red during step 5, it means the erase has failed. Repeat the steps
starting with 2.
If you haven't already downloaded the latest release of CircuitPython for your board,
check out the installation page(). You'll also need to load your code and reinstall your
libraries!
For SAMD21 non-Express boards that have a UF2
bootloader:
Any SAMD21-based microcontroller that does not have external flash available is
considered a SAMD21 non-Express board. Non-Express boards that have a UF2
bootloader include Trinket M0, GEMMA M0, QT Py M0, and the SAMD21-based
Trinkey boards.
If you are trying to erase a SAMD21 non-Express board, follow these steps to erase
your board.
 1. Download the erase file:
SAMD21 non-Express Boards
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