CP System II
Template:Short description Template:About Template:Use mdy dates Template:Infobox information appliance
The Template:Nihongo, also known as Capcom Play System 2<ref>Template:Cite book</ref> or CPS-2 for short, is an arcade system board that was the successor to Capcom's CP System, CP System Dash and Capcom Power System Changer arcade hardware. It was first used in 1993 for Super Street Fighter II and was succeeded by the CP System III hardware in 1996, of which the CPS-2 would outlive by over four years. New releases for the system were produced until the end of 2003, ending with Hyper Street Fighter II. Technical support for the CPS-2 ended on February 28, 2019.<ref name="csend2" />
Like its predecessor, games can be exchanged without altering the core hardware. The CP System II uses separate daughterboards enclosed in plastic cases to store both the games and the main board on, which are then put together so that the games can be played. Unlike its predecessor, however, games are encrypted, and must be decrypted via a decryption key stored on the main board's battery-backed memory to run them.
History
Capcom announced the development of the CP System II (or CPS-2) in 1990. They had planned to complete and release the CP System II hardware in 18 months. They also originally had plans for the system to be capable of 3D graphics.<ref>Template:Cite magazine</ref>
The earlier Capcom system board, the original CP System (or CPS-1), while successful, was very vulnerable to bootleggers making unauthorized copies of games. In order to rectify the situation, Capcom took the CP System hardware (with QSound) 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.Template:Cn
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 very similar to 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.Template:Cn
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 generally referred to as a "suicide battery". It is possible to bypass the original battery and swap it out with a new one<ref>Template:Cite web</ref> in-circuit, but this must be done before the original falls below 2V or the keys will be lost. Consequently, the board would just simply die, even if used legally it would not play after a finite amount of time unless a fee was paid to Capcom to replace it.
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<ref>Template:Cite web</ref> 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 Andreas Naive (Template:Webarchive<ref>Template:Cite web</ref>) and Nicola Salmoria. It has been determined that the encryption employs two four-round Feistel ciphers with a 64-bit key.<ref>MAME source - cps2crypt.cpp</ref><ref>Template:Cite web</ref> 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 II security programming, enabling the clean "de-suicide" and restoration of any dead games without hardware modifications.<ref>Template:Cite web</ref><ref>Template:Cite web</ref>
Capcom ceased manufacturing the CP System II hardware on December 22, 2003, with Hyper Street Fighter II being the final game released for the hardware. Capcom ended most of the technical support for the hardware and its games on March 31, 2015.<ref name="csend">Template:Cite web</ref> Battery replacements ended on February 28, 2019,<ref name="csend2">Template:Cite web</ref> ending all official support of the CP System II hardware and software.
Region colors
| Region | Case | Version screen |
|---|---|---|
| Japan | Green plastic | White text |
| U.S.A. | Blue plastic | Red text |
| Euro/Etc./World | Blue plastic | Blue text |
| Asia | Grey plastic | Yellow text |
| Hispanic | Orange plastic | Green text |
| Brazil | Orange plastic | Magenta text |
| Oceania | Blue plastic | Orange text |
| Rental (any of above) | Yellow plastic | (Any of above) |
| (Any of above) | Black metal "all-in-one" | (Any of above) |
Technical specifications
- CPU:<ref name=mame>Template:Cite web</ref>
- Capcom custom chipset:<ref name=mame/>
- GPU: CPS-A & CPS-B Graphics Processors @ 16 MHz (same as CPS-1)
- Sound chip: Lucent DL-1425 Q1 QSound DSP16A Processor @ 4 MHz
- DRAM Refresh Controller: DL-2227
- I/O Controller: DL-1123
- Display:
- Active resolution: 384×224 pixels<ref name=system16>Template:Cite web</ref>
- Overscan resolution: 512×262 (262 scanlines)<ref>Template:Cite web</ref>
- Sprites: 900 on screen<ref name=system16/>
- Colors:
- RAM: 1328 KB (1 MB FPM DRAM, 304 KB SRAM)
- A-Board: 1 MB FPM DRAM,<ref name=mame/><ref>Template:Cite web</ref> 280 KB SRAM (256 KB video, 16 KB I/O, 8 KB sound)<ref name=mame/>
- B-Board: 16 KB SRAM (2× 8 KB)<ref name=mame/>
- Communication Board: 8 KB SRAM<ref name=mame/>
- Maximum ROM capacity: 322 Mbit<ref name=system16/> (40.25 MB)
- Dimensions (A+B board pair): 40 x 27 x 8 cm