Datasheet

Accessing SPI Flash

Arduino doesn't have the ability to show up as a 'mass storage' disk drive. So instead we must use CircuitPython to do

that part for us. Here's the full technique:

Start the bootloader on the Express board. Drag over the latest circuitpython uf2 file

After a moment, you should see a CIRCUITPY drive appear on your hard drive with boot_out.txt on it

Now go to Arduino and upload the fatfs_circuitpython example sketch from the Adafruit SPI library. Open the

serial console. It will successfully mount the filesystem and write a new line to data.txt

Back on your computer, re-start the Express board bootloader, and re-drag circuitpython.uf2 onto the BOOT

drive to reinstall circuitpython

Check the CIRCUITPY drive, you should now see data.txt which you can open to read!

Once you have your Arduino sketch working well, for datalogging, you can simplify this procedure by dragging

CURRENT.UF2 off of the BOOT drive to make a backup of the current program before loading circuitpython on. Then

once you've accessed the file you want, re-drag CURRENT.UF2 back onto the BOOT drive to re-install the Arduino

sketch!

https://learn.adafruit.com/adafruit-feather-m0-express-designed-for-circuit-python-

circuitpython

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