UF2 Bootloader Updates Available in circuitpython.org

Now it’s a lot easier to find the latest UF2 bootloader for your Adafruit or other microcontroller board. Go to circuitpython.org/downloads, choose your board, and look for a download section like what you see below. Download the bootloader updater from the link and follow the instructions for updating your board. (A very small number of third-party boards aren’t listed yet; contact the manufacturer.)

Important UF2 Bootloader Update for SAMD51 M4 Boards

A new version of the UF2 bootloader is available for SAMD51 M4 boards, such as the Metro M4 Express, Feather M4 Express, ItsyBitsy M4 Express, PyPortal, PyGamer, PyBadge, and others. Version v3.9.0 or later fixes a rare but annoying problem that occasionally erases parts of internal flash memory when the board is plugged in or power-cycled. Both Arduino and CircuitPython are affected. We highly recommend that you update your bootloader if you have a SAMD51 M4 board. Download the updater from the circuitpython.org/downloads page for your board, and follow the instructions to update. Update instructions will also be added to the Learn Guide for each board.