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_at_siconic.com
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Received on Thu Apr 08 1999 - 05:16:47 BST