Emax

from memory, the standard floppy connector tends to have signals on top, 
and GNDs on bottom... So if the cable is upside down, you're shorting 
lots of floppy controller signals to GND. not good.

Perhaps you damaged the disk sense switch, and so it's always reporting 
to the emax that a floppy is in the drive, as soon as you turn it on, 
and so the emax tries o read this phantom floppy, only to find there's 
no data there...

What happens if you put a known good disk in the drive before powering 
it on?