Those were the days
Pre IWM (Integrated Woz Machine IC) originanal Apple II floppy drive
controller.
One package of flipflops, a prom, one counter, not too much else.
(I remember being suitably impressed at the time).

             http://www.freepatentsonline.com/4210959.pdf

Save PDF and open makes for far better viewing than using their frame.

 R
--=20
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