Uncheck the box at the top, labeled Use Autoplay for all
devices
Making your own UF2
Making your own UF2 is easy! All you need is a .bin file of a program you wish to flash and
the Python conversion
script
(https://adafru.it/vZb)
. Make sure that your program was compiled to start at 0x2000 (8k) for M0 boards or
0x4000 (16kB) for M4 boards. The bootloader takes up the first 8kB (M0) or 16kB (M4). CircuitPython's
linker
script
(https://adafru.it/CXh)
is an example on how to do that.
Once you have a .bin file, you simply need to run the Python conversion script over it. Here is an example from the
directory with uf2conv.py. This command will produce a firmware.uf2 file in the same directory as the source
firmware.bin. The uf2 can then be flashed in the same way as above.
Installing the bootloader on a fresh/bricked board
If you somehow damaged your bootloader or maybe you have a new board, you can use a JLink to re-install it.
Here's a
short writeup by turbinenreiter on how to do it for the Feather M4 (but adaptable to other boards)
(https://adafru.it/ven)
# For programs with 0x2000 offset (default)
uf2conv.py -c -o build-circuitplayground_express/firmware.uf2 build-circuitplayground_express/firmware.bin
# For programs needing 0x4000 offset (M4 boards)
uf2conv.py -c -b 0x4000 -o build-metro_m4_express/firmware.uf2 build-metro_M4_express/firmware.bin
© Adafruit Industries
https://learn.adafruit.com/adafruit-feather-m4-express-atsamd51
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