I wrote in my previous post about alternative solutions instead of the Arduino. The set-up worked, sort of. The Arduino Uno was connected to the Amiga floppy drive, it was kicking out an index pulse and control was working. However the data signal when I looked at it on a scope seemed to be odd. It appeared not to be going to TTL but only 0v to 3v. Even after putting through a level shift the Arduino had trouble picking it up, I assume due to the speed.
I could upgrade and try a Due board but considering the STM32 boards are only a few pounds I thought I would give them a try. Secondly I am not 100% sure the Amiga drive is working. I need to test it, again, on my Amiga, but thought in the mean time I would switch to an old PC floppy disk drive.
And so I have an HD PC floppy connected to a STM32. I have just got it doing the basics to start with, moving heads, spinning the motor, etc. The next step is to see if I can clock in some data and time the pulses.