21 Second Back up – Spiral track protection

A new format of C64 copy protection found 25+ yrs after it’s release?

Most of use know that Bounty Bob was likely to be the hardest C64 game out to copy. But have you tried to copy 21 Second back up? Well it pretty much impossible to copy also. It wasn’t until just recently that Jim Drew (interviewed here) maker of the SuperCard got his hands on an original copy of it. Here is Jim’s Quote from his post on LEMON64,

“Because this disk uses true spiral track protection.
Tracks 10, 10.5, and 11 contain valid data that was written WHILE the head was stepping.
So, the data (which is 10 x 512 bytes long) is written on an ‘arc’ as the disk spins
and the head steps between tracks 11.0->10.5->10.0->10.5->11.0″

Goto the Lemon64 link above to learn more!!

 

2 thoughts on “21 Second Back up – Spiral track protection

  1. This isnt new – and described in the “anti cracker book” – like most of the other stuff some people are discovering these days.

    • I far as I know this book is only in Germany, that could be the problem. Do you have an English version to post?

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