This site says that for 1.62 mb disks (1680K), go like so:

fdformat /dev/fd0u1680

/sbin/mkfs -t msdos /dev/fd0u1680

This is the "DMF" format. He says don't try for the 1720K "MDF" format. That might write on the unfinished part of the disk.

read "man fdformat" if you want to see how to format other sizes.

-- PaulJohnson - 16 Sep 2003