PlayStation CD-ROM

The PlayStation CD-ROM was a type of CD-ROM that exhibited a black coating, and was first used with the Sony PlayStation home console. The discs incorporated the CD-ROM/XA extension jointly developed by Sony and Philips in the aftermath of Sony's failed partnership with Nintendo over the unreleased SNES-CD console.

The black coating with both an anti-piracy and anti-counterfeiting attempt aimed not only at hindering the ability for "normal" CD-ROM drives to read the disc's contents (which, while true that some optical drives had difficulties, the vast majority of drives were able to read them), but also providing a way for the consumer to know a "genuine" disc (i.e., with the black coating), from a "copied" disc (which would have the silver, gold or gray coatings common to CD-Rs and CD-RWs of the time).

However, this format of CD-ROM did contain anti-piracy measures; the CD, when created, would include intentional imperfections in the track recording. A normal CD-ROM drive would disregard these imperfections, and correctly read the CD anyway, but the PlayStation was capable of interpreting these imperfections into a set of binary data. This data would actually inform the PlayStation which region (Japan, North America, or Europe) the disc was manufactured for. Since the PlayStation was always sold region-locked, the console was able to use this data to ensure that discs intended for one region couldn't be played on a console from another region.

This early form of DRM led to the creation of mod chips, which were capable of bypassing checks like this. However, some video games, such as Spyro: Year of the Dragon, went further in their anti-piracy checks to combat early-generation mod chips. This video game, while the game was playing, would ask the console to check the game's region. During gameplay, this cannot be done due to the disc drive being in use, and this check should return an error in non-modded consoles. However, the mod chip, if installed, would return the region anyway; mod chips manufactured later would emulate this behavior, earning the nickname "stealth chips".

If the console reported a region during the check, Spyro: Year of the Dragon would make a note of this, and while it would play normally at first, it would get to the point where the player would be informed that they were running a modified copy of the game that may introduce unintended behaviors. The game would then introduce subtle annoyances to the player, such as random crashes, and eggs that had been previously collected going missing from the player's inventory; the eggs could still be re-obtained, however, but it would soon get to the point where re-obtaining these eggs would become a bigger time investment than playing the rest of the game.

The game itself, however, was impossible to complete in this state; during the final boss fight, the game would crash and in the process, overwrite the player's save file, eliminating all progress made.