General Floppy Info
Floppy Drive Interface Pinouts

Diskette Drive and Diskette Issues
Repairing the 1.44MB Drive (by Al Savage)

5.25" External Drive Adapter

4869 Ext Floppy
Data Migration Facility

DASDDRVR From a book [need to research] More human readable...

Floppy Disk Controllers
Programming Floppy Disk Controllers
Intel
   82077AA
   82077SL
   82078 (44 pin)
   82078 (64 pin)
National Semiconductor
   PC8477B
     Similar to -A, differences are Motor On Time (MNT) in Mode 1,
     NSC command results 8477B (73H) and 8477A (72H)
NEC
   µPD765
   µPD72065