Posted by vibratory manner of working at 10:39 AM on June 13, 2016 So is 4am cracking because the perfect dumps can't be produced here? (In which case, why not?) Or because the emulation isn't up to snuff? (in which case, understandable.) Or is 4am cracking because that's their (very impressive) skill set and these broader questions are off-base? A slient crack is better than a sloppy crack, but best is beating the copy protection by having a perfect dump and good enough emulation that any copy protection simply passes. Right, I get the benefit of a silent, documented crack versus whatever junk they did in the past, but why is a crack of any kind needed at this point? We have the technology to accurately dump any kind of disk-level shenanigans, which is what SPS is up to, and if you read their write-ups they've seem some shenanigans. 4am is re-cracking them, producing silent cracks that are all carefully documented, and doing it inside a constrained environment. That's not what this project is about afaict, most of these programs were cracked ages ago. It was a really cool analog technique to beating digital copy protection. The hack that I remember was to gently lift the eject tab on the floppy drive a few seconds after the program was loading, triggering some disk errors, which would suffice to side-step that copy protection. I think that the game would detect this by reading the same sector a few times: if it got random results, that indicated that it was genuine, but if it always got the same results, it knew it was a fake copy. If you copied the disk, although the copy might have bad data, in those sectors, it would be a clean copy of bad data, so when running it wouldn't have actual disk errors.

These sectors when read, would give disk errors.

I seem to remember that the publisher would make the floppies, then intentionally erase a few sectors. I can't remember the game, but there was a copy-protection scheme on an Apple game that had something to do with reading (intentionally) bad sectors from the floppy disk.

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