To celebrate the 25th anniversary of the Atari 7800 ProSystem's release, the Atari Historical Society has unofficially released the source code for over a dozen of the system's games such as Centipede, Xevious, Robotron, and more.

According to the Atari Museum site, the games were rescued from Atari ST format diskettes that were thrown out when Atari shuttered one of its offices in 1996. "I hope these will be great learning tools and the basis for code for many coders to develop on the 7800," says Atari Museum founder Curt Vendel.

He continues, "And just as the Atari 2600 developers have stretched the boundaries and created games no one would've imagined in their wildest dreams, it is my hope that this same enthusiasm can carry over to an open and active 7800 developers community and bring forth games that would make even a NES owner envious."

The Atari Historical Society also posted details about a newly discovered prototype of the original High Score Cartridge (HSC), the planned but never released 7800 peripheral that was designed by General Computer Corp. and recorded players' high scores for multiple games. You can see documents and specifications detailing the HSC's design and production here.

Online retailers have sold reproduction versions of the HSC for several years now, but Vendel says that he plans to produce 25 special edition Atari 7800 25th anniversary High Score cartridges with a new label design. Unfortunately, he isn't taking preorders, but he promises to make an announcement sometime this month about when the special edition carts will go on sale.