CP System II


The CP System II or CPS-2 is an arcade system board that Capcom first used in 1993 for Super Street Fighter II. It was the successor to their previous CP System and Capcom Power System Changer arcade hardware and was succeeded by the CP System III hardware in 1996, of which the CPS-2 would outlive by over four years. The arcade system had new releases for it until the end of 2003, ending with Hyper Street Fighter II.

History

The earlier Capcom system board, the original CP System, while successful, was very vulnerable to bootleggers making unauthorized copies of the games. In order to rectify the situation, Capcom took the CP System hardware with minimal changes and employed encryption on the program ROMs to prevent software piracy. Due to the encryption, the system was never bootlegged until unencrypted program data became available.
The CP System II consists of two separate parts; the A board, which connects to the JAMMA harness and contains components common between all CP System II games, and the B board, which contains the game itself. The relationship between the A and B board is basically the same as that between a home video game console and cartridge. CP System II A and B boards are color-coded by region, and each board can only be used with its same-colored mate. The exception to this is that the blue and green boards can be used together.
The B boards hold battery-backed memory containing decryption keys needed for the games to run. As time passes, these batteries lose their charge and the games stop functioning, because the CPU cannot execute any code without the decryption keys. This is known to hobbyists as the "suicide battery". It is possible to bypass the original battery and swap it out with a new one in-circuit, but this must be done before the original falls below 2V or the keys will be lost.
Consequently, the board would just die anyway, meaning even if used legally it would not play after a finite amount of time.
Due to the heavy encryption, it was believed for a long time that CP System II emulation was next to impossible. However, in January 2001, the CPS-2 Shock group was able to obtain unencrypted program data by hacking into the hardware, which they distributed as XOR difference tables to produce the unencrypted data from the original ROM images, making emulation possible, as well as restoring cartridges that had been erased because of the suicide system.
In January 2007, the encryption method was fully reverse-engineered by and Nicola Salmoria. It has been determined that the encryption employs two four-round Feistel ciphers with a 64-bit key. The algorithm was thereafter implemented in this state for all known CPS-2 games in MAME.
In April 2016, Eduardo Cruz, Artemio Urbina and Ian Court announced the successful reverse engineering of Capcom's CP System 2 security programming, enabling the clean "de-suicide" and restoration of any dead games without hardware modifications.

Region colors

RegionCaseVersion screen
JapanGreen plasticWhite text
U.S.A.Blue plasticRed text
Euro/Etc./WorldBlue plasticBlue text
AsiaGrey plasticYellow text
HispanicOrange plasticGreen text
BrazilOrange plasticMagenta text
OceaniaBlue plasticOrange text
Rental Yellow plastic
Black metal "all-in-one"

Technical specifications

English titleRelease dateDeveloperJapanese titleGenre
Super Street Fighter II: The New Challengers
Super Street Fighter II: Tournament Battle
1993-09-10CapcomSuper Street Fighter II
Head-to-Head Fighting Game
Eco Fighters1993-12-03CapcomUltimate Ecology
Shoot 'em up
'1994-01-13CapcomDungeons & Dragons: Tower of Doom
Beat 'em up
Super Street Fighter II Turbo1994-02-23CapcomSuper Street Fighter II X: Grand Master Challenge
Head-to-Head Fighting Game
Alien vs. Predator1994-05-20CapcomAlien VS Predator
Beat 'em up
'1994-07-05CapcomVampire: The Night Warriors
Head-to-Head Fighting Game
Ring of Destruction: Slammasters II1994-08-08CapcomSuper Muscle Bomber: The International Blowout
Head-to-Head Fighting Game
Armored Warriors1994-09-16CapcomPowered Gear: Strategic Variant Armor Equipment
Beat 'em up
'1994-12-08CapcomX-Men: Children of the Atom
Head-to-Head Fighting Game
'1995-03-02CapcomVampire Hunter: Darkstalkers' Revenge
Head-to-Head Fighting Game
'1995-04-20CapcomCyberbots: Full Metal Madness
Head-to-Head Fighting Game
Street Fighter Alpha1995-06-05CapcomStreet Fighter Zero
Head-to-Head Fighting Game
'1995-09-22CapcomRockman: The Power Battle
Platformer
Marvel Super Heroes1995-10-24CapcomMarvel Super Heroes
Head-to-Head Fighting Game
'1995-12-07Capcom19XX The War Against Destiny
Shoot 'em up
'1996-02-06CapcomDungeons & Dragons: Shadow over Mystara
Beat 'em up
Street Fighter Alpha 21996-02-27CapcomStreet Fighter Zero 2
Head-to-Head Fighting Game
Super Puzzle Fighter II Turbo1996-05-29CapcomSuper Puzzle Fighter II X
Puzzle game
'1996-07-08CapcomRockman 2: The Power Fighters
Platformer
Street Fighter Alpha 2 Gold1996-08-05CapcomStreet Fighter Zero 2 Alpha
Head-to-Head Fighting Game
Quiz Nanairo Dreams: Nijiirochō no Kiseki1996-08-26CapcomQuiz Nanairo Dreams: Nijiirochō no Kiseki
Quiz game
X-Men vs. Street Fighter1996-09-09CapcomX-Men vs. Street Fighter
Head-to-Head Fighting Game
Battle Circuit1997-03-19CapcomBattle Circuit
Beat 'em up
Vampire Savior: The Lord of Vampire1997-05-19CapcomVampire Savior: The Lord of Vampire
Head-to-Head Fighting Game
Marvel Super Heroes vs. Street Fighter1997-06-20CapcomMarvel Super Heroes vs. Street Fighter
Head-to-Head Fighting Game
Capcom Sports Club1997-07-22CapcomCapcom Sports Club
Sports game
Super Gem Fighter Mini Mix1997-09-04CapcomPocket Fighter
Head-to-Head Fighting Game
Vampire Hunter 2: Darkstalkers' Revenge1997-09-13CapcomVampire Hunter 2: Darkstalkers' Revenge
Head-to-Head Fighting Game
Vampire Savior 2: The Lord of Vampire1997-09-13CapcomVampire Savior 2: The Lord of Vampire
Head-to-Head Fighting Game
'1998-01-12CapcomMarvel vs. Capcom: Clash of Super Heroes
Head-to-Head Fighting Game
Street Fighter Alpha 31998-06-29CapcomStreet Fighter Zero 3
Head-to-Head Fighting Game
Giga Wing1999-02-22TakumiGiga Wing
Shoot 'em up
'1999-05-27CapcomJyangokushi: Haō no Saihai
Puzzle game
Dimahoo2000-01-21Eighting/RaizingGreat Mahō Daisakusen
Shoot 'em up
'2000-04-12TakumiMars Matrix
Shoot 'em up
2000-06-20Eighting/Raizing1944 The Loop Master
Shoot 'em up
Mighty! Pang2000-10-10MitchellMighty Pang
Platformer
Progear2001-01-17CaveProgear no Arashi
Shoot 'em up
Puzz Loop 22001-02-05MitchellPuzz Loop 2
Puzzle game
Janpai Puzzle Chōkō2001-08-20MitchellJanpai Puzzle Chōkō
Puzzle game
Hyper Street Fighter II: The Anniversary Edition2003-12-22CapcomHyper Street Fighter II
Head-to-Head Fighting Game