Copy protection, otherwise known as “access controls”, was used on media for various systems to protect the investments of the people involved in creating the software content. Various techniques were used to this end, especially on the Commodore Amiga due to the systems popularity and the flexibility of the floppy controller.
Note that copy protection, especially on the Amiga should not be confused with custom disk formats. Protection was used specifically to stop people copying the game, and while using a custom format has this side effect, but it is not generally its primary purpose.
Some of the copy protection techniques we have found are:
- Flakey Bits, random data is read, which becomes non-random when copied.
- Long/short tracks, the data is packed on a track, more and less dense respectively. Their precense may or may not be checked in the program code.