Josh Dersch <derschjo at mail.msu.edu> wrote:
I have both a 16FDC and a 64FDC (for the moment) and
right now I have it
wired to a single
5.25" drive (w/proper termination). I've
tried three different drives --
a Tandon TM-100, an
unmodified 1.2M 5.25" drive, and one that's
modded to spin at 300rpm.
Same exact behavior on all three.
Sounds like you have the basics covered. Are you running your Z-80 CPU
board at 4MHz?
Though I'd find it unlikely that *both* controllers would be seriously out
of adjustment, I'd also check that the data separator oscillator is at the
right frequency. Instructions are in the FDC user manuals for checking and
adjusting that.