3 Feb
2021
3 Feb
'21
noon
I'll add just a bit with respect to floppy disks on an MCU.
One reason to put histogram and peak-detection in the MCU firmware is
that for a disk you never know how far out of alignment the original
(recording) drive might be. A drive used to record something out of
alignment can yield garbage on a blind capture.
A drive that allows for adjustment means that you can sample a track,
and adjust until you see nice clean peaks. Blind-on-the-fly recovery
makes this a lot more difficult. You can certainly add some primitive
decoding for FM, MFM, MMFM and a few varieties of GCR as a sanity check,
but looking at spectral peaks is a first-line diagnostic.
--Chuck