9 Dec
2003
9 Dec
'03
10:23 p.m.
--On Tuesday, December 09, 2003 20:45:45 -0800 "Peter C. Wallace"
<pcw(a)mesanet.com> wrote:
But then you need to know what the bitstream is, which goes against
what we've been saying. And what about different encoding methods:
what happens when someone wants to emulate a drive on a system you've
not thought of?
Actually, I don't think you need to know the encoding scheme at all. I
believe the precomp (if/when applied) depends only on the sequence of
transitions in the data.
--
Pete Turnbull
Network Manager
University of York, UK
On Tue, 9 Dec 2003, Eric Smith wrote:
> The part of the ST-506 disk emulation that's of most concern to me
> is whether anything needs to be done about write precompensation.
[...]
I'm
guessing that it won't be
enough to cause reads to fail MOST of the time, but it will reduce
the timing margins enough to that it could potentially cause
occasional soft errors.
Right, one option would be for the emulator to have a FM, MFM or RLL
front end and actually decode the bitstream. Then the write-precomp
could be undone...