Hello.
Unfortunately I don't have a RK05, even if I REALLY would to know
somebody in willing to sell one...
Anyway, I followed the former and the latter post about PLL to sync
12-sector cartridges as 16-sector,
but I have some question about how the circuit should work.
In the hardware sectoring, the pulses is needed to identify in precise
way the physical boundary between
one sector and the neightbors.
Clearly the 12-sectors will have 12 dents, while the 16 -sectors 16
dents.. plain.
Now I could take a signal coming from a 12-sectors cartridge sensor,
pass it through a
PLL and produce a signal with 16/12 times the frequency, that is
synchronized with the original
signal... could it work?
Maybe I missing something, but I think is not that easy...
In fact, you expect to produce 4 pulses every 3 pulses of the reference
signal.
As the 4/3 ratio is not an integer multiple, only 1 every 4 pulses will
be aligned with the hardware pulses,
thus we would have a phase uncertain of 1/3 of physical hardware sector.
Probably, if the cartridge is started and synchronized, it could
continue to work correctly until the
whole stuff is stopped and restarted. In this situation it could work in
33% of the cases,
being misaligned of 1/3 or 2/3 of sector in remaining cases..
To fix it all, there would be a way to generate a secondary pulse to
identify a particular dent.
In this way, the regenerated sectors would always synchronize to the
very same phase,
removing the phase uncertain...
Does it sound correct?
Andrea