31 Oct
2006
31 Oct
'06
5:03 p.m.
On 31 Oct 2006 at 23:44, Tony Duell wrote:
Certainly the read output will give a fixed-width
pulse for every flux
transtion on the media (so don't expect the read data output to
faithfully reproduce the pulses you fed into the write data line, in fact
just the leading edges will be preserved). I had an idea that if the flux
transitions were too far apart then some part of the read chain got
confused, but maybe not.
I know that most drives have low-pass filtering on them, but I'm not
so sure about high-pass. The OP was asking about a 50 KHz data rate,
which I think is probably within the bandpass of most drives, at
least at the double-density (250K) rate. I do recall that some older
drives using the MC3470 read amp will belch out a false read pulse if
it's been too long since the last one.
Cheers,
Chuck