Greaseweazle is a set of tools for accessing a floppy drive at the raw
flux level. This allows reading and writing of raw flux data, as well as
conversion between various floppy disk image formats. It supports a wide
range of floppy disk formats including IBM, Amiga, Commodore 64, Apple,
and Macintosh.

The "gw" command-line tool communicates with a Greaseweazle USB device to
read, write, and manipulate floppy disks at a level below the normal
operating system disk interface.