Adafruit provides a USB Mass Storage Device firmware for the Adafruit Floppy FeatherWing paired with the Adafruit Feather RP2040.

With this firmware installed, you can directly read a DOS/Window (FAT)-formatted 1.44MB floppy disk on standard computers.

Under the covers, the RP2040 is reading the raw flux and performing MFM decoding before it sends the decoded data to your PC.

Upload the firmware to the Feather RP2040

Grab the latest release from GitHub (pick the file named "feather_rp2040_tinyusb.zip" and unzip it).

Plug in the Feather and then place it in bootloader mode by holding the BOOT button and clicking RESET.

Drag the msd_test uf2 file to the RPI-RP2 volume. It will automatically restart with the new firmware.

Use the USB Floppy Drive

Insert a floppy drive and then click the device's reset button. It will connect to your computer as a USB floppy disk. Note that the floppy disk is read-only, and only 1.44MB PC-format disks can be used.