Floppy disk interface
In case you need a dose of self-injected early 80's technology, here's some light reading.  This tells you a little about the floppy disk interface for those $10 devices with 5.25" floppies, the precursor of 3.5"

http://bitsavers.informatik.uni-stuttgart.de/pdf/westernDigital/WD100x/61-031050-0030_WD1002-05_HDO_OEM_Manual_Jul83.pdf

Here's some more info on the FDC chip interface
ftp://ftp.oldskool.org/pub/drivers/Central%20Point/OptionBoard/website%20mirrors/retro.icequake.net%20Option%20Board%20website%20mirror/dob/files/bleuge/00info/8272sp.htm

it is definitely old-skool, but it worked.