CPS-3

The or CPS-3 is an arcade system board that was first used by Capcom in 1996 with the arcade game '' Red Earth''. It was the second successor to the CP System arcade hardware, following the CP System II. The arcade system saw new releases up until mid 1999. Technical support for the CPS-3 ended on February 28, 2019. It would be the last proprietary system board Capcom would produce before moving on to the Dreamcast-based Naomi platform.

Like its forerunners, games can be exchanged without altering the core hardware. The CP System III uses CDs instead of separate daughterboards to store the games on, which are then loaded onto the system's CD drive to be stored into memory to allow for it to be played. Like its predecessor, games are encrypted, and must be decrypted via game-specific security cartridges, which will decrypt the contents stored within the system memory in run time.

History

The CP System III became the final arcade system board to be designed by Capcom. It features a security mechanism; games are supplied on a CD, which contains the encrypted game contents, and a security cartridge containing the game BIOS and the SH-2 CPU with integrated decryption logic, with the per-game key stored in battery-backed SRAM. Capcom chose the CD medium in order to keep down the price of the system.

In a change from its predecessors, the CP System III consists of a single board instead of two separate boards. The board contains components common to all CP System III games, and includes a slot for the security cartridge. The games themselves are stored on a CD instead of on a separate board, which is then readable by the provided SCSI CD-ROM drive that is connected to the main board. The CP System III has extensive sprite scaling capabilities that all games for the system used. It does not contain the QSound sound chip used on its predecessor, the CP System II, and in its place is a custom 16-channel stereo sound chip. One of the unique features of the CP System III is widescreen support for certain games; only one game has officially made use of this feature, which is '' Street Fighter III: 2nd Impact''.

When the CP System III board is first powered on, the contents of the CD are loaded into a bank of Flash ROM SIMMs on the motherboard, where it is executed. The program code is then decrypted at run time via the security cartridge. The security cartridge is sensitive to any sort of tampering, which will result in the decryption key being erased and the cartridge being rendered useless. Games become unplayable when the security cartridge has been tampered with or when the battery inside the security cartridge dies. The lone exception is ''Street Fighter III: 2nd Impact'', which uses a default set of decryption keys that are written to dead cartridges on boot, making it the few, if not the only CPS-3 games prevalent after support was dropped, due to its immunity to cartridge tampering or suicide.

In June 2007, the encryption method was reverse-engineered by Andreas Naive, making emulation possible. Later developments led to the eventual bypassing of the suicide and security routines of the games as well as a development of a so-called "super cartridge" capable of running all CPS-3 games.

Capcom ceased manufacturing the CP System III hardware after 1999. Capcom ended most of the technical support for the hardware and its games on March 31, 2015. Battery replacements ended on February 28, 2019, ending all official support of the CP System III hardware and software.

Specifications

* Main CPU: Hitachi HD6417099 ( SH-2) at 25 MHz
* RAM:
** 512 KB Work RAM
** 512 KB Sprite RAM
** 8 MB Character RAM
** 256 KB Color RAM
** 32 KB SS RAM
* Storage:
** SCSI CD-ROM drive
** Flash ROM: Variable amount, up to 8 × 16 MB
* Sound chip: 16-channel 8-bit sample player, stereo
* Maximum color palette: 16 million shades''Computer and Video Games'', October 1996
page 10

* Maximum number of colors on screen: 32,768 (15-bit colour, 555 RGB)
** Palette size: 131,072 pens
** Colors per tile (backgrounds / sprites): 64 (6 bits per pixel) or 256 (8 bits per pixel), selectable
** Colors per tile (text overlay): 16 (4 bits per pixel)
* Maximum number of objects: 1024, with hardware scaling
* Scroll faces: 4 regular + 1 text overlay 'score screen' layer
* Scroll features: Horizontal & vertical scrolling, ,
* Framebuffer zooming
* Color blending effects
* Hardware RLE decompression of 6 bpp and 8 bpp graphics through DMA
* Resolution, pixels: 384×224 (standard mode) / 496×224 (widescreen mode)

List of games (6 games)

All six games are developed by Capcom and are all head-to-head fighting games.

See also

* CP System
* CP System II

References

External links

CPS-3 at System16: The Arcade Museum

CPS-3 memory, suicide and SCSI information

CPS-1, CPS-2 and CPS-3 releases comparison at UVL

{{DEFAULTSORT:Cp System Iii
Capcom arcade system boards
SuperH architecture