9 Dec
2009
9 Dec
'09
1:17 a.m.
It's an interesting question about how much oversampling is
necessary.
Most modern 3.5" floppies are rated with an ISV of around +/- 3% and
CSV of about about half that. 5.25" legacy floppies, particularly
those with belt drives go considerably outside of that.
Data separators expect some pretty wide variations; the lowly WD9216
(used on a lot of older FDC boards) claims to be able to adjust to +/-
30% of nominal center (reference) frequency.
So how much oversampling is optimum in light of legacy hardware
performance and how much is gilding the lily?
--Chuck