On Wed, 7 Apr 1999, Max Eskin wrote:
On 8 Apr 1999, Eric Smith wrote:
> These fellows
> spent a couple of sessions talking about and demonstrating the screwy means
> by which certain game vendors in the Apple market were "protecting" their
> wares by altering the timing of the positioning routine, thereby making it
> possible to write tracks "off the track" by changing the time delay
between
> a known cylinder position and the point at which the specific track was to
> be written. This made it impossible for someone using the stock timing of
> the positioning mechanism to read the diskettes so written.
How does this work? Do you mean that the disk drive has no internal means
of judging whether or not it's on the right track and that this is
determined by the contents of the disk?
Basically, yes. The track and sector are stored in the sector header of
each sector, among other data.
Sellam Alternate e-mail: dastar(a)siconic.com
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