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Mod chip)
A modchip is a device used to play import games and/or circumvent the digital rights management of many popular game consoles, including the Xbox and PlayStation. Almost all modern disc-based console gaming systems, with the notable exception of the Sega Dreamcast have hardware-based schemes which ensure that only officially sanctioned games may be used with the system, also making simple bitwise copying of games impossible. For example, Microsoft must cryptographically "sign" every Xbox game with their 2048-bit private key for it to work in an unmodded Xbox. Modchips circumvent this protection by effectively routing around the security check. Many mod chips require some experience to install, especially since they require to be soldered, though recently, solderless mod chips have made headway.
Xbox modchips now allow a user to completely circumvent the BIOS on-board the video game console's mainboard. This allows a console to run code, such as user-created applications or games, not licensed or published by Microsoft. One of the main uses in the modding community of this ability is to provide a non-Microsoft BIOS that does not contain any copyrighted code that will run the Linux Operating System from a DVD or the Xbox hard drive.
All PlayStation 2 original discs have a series of pits and bumps before the data region, which cannot be read or writen to using a conventional CD Burner. Due to this, discs which have been copied using conventional means will not have this authentication region present, and therefore the disc will fail to authenticate.
PlayStation 2 modchips come in two types, a "swap" modchip and a "no-swap" modchip.
The "swap" modchips are not as advanced as their sucessors. In order to boot a non-original disc, the operator must first load an original disc, then use the modchip to swap the disc out for a non-original without the PS2 knowing. Once this swap has been performed, the operator can instruct the PS2 to load the code from the non-original disc. Since the PS2 does not realize the disc has been changed, the authentication code is never re-checked. Unlike "no-swap" modchips, these chips do not affect the BIOS. They actually circumvent the protection in the same way as an original Playstation chip (modified originally by Alex Lau for Playstation 2, and first sold by Neo Technology). They simply input the string "S,C,E,A" (Sony Computer Entertainment America, or SCEE for Europe). On the original Playstation, the "pits and bumps" that were read checked for "S,C,E,A". The Playstation 2 authentication is more complex, but it reads the data from the first disc, hence the swap. Other mods are connected in between the ribbon cable which controls the eject function of the DVD drive and the mainboard, without the Playstation 2 noticing. These mods do not inject SCEA data and are not as reliable.
The "no-swap" modchips, rather than replacing the existing BIOS with a new BIOS that allows backups and imported games to run, the modchip sends a series of signals to the BIOS which are present when a CD or DVD disk is an original. This effectively allows any disc without the special authentication data to run. These modchips are usually more difficult to install into the console, requiring usually 19 to 24 wires to be soldered to the mainboard by the installer.
Modchips were made illegal in the US by the Digital Millennium Copyright Act (DMCA). This angered many people because they couldn't play homemade games. In early 2003, iSONEWS.com was taken over for selling modchips. However, in many countries modchips remain legal for backup and import uses.
Many companies are now manufacturing modchips without any illegal (offending) BIOS code loaded onto the flash RAM of the chip module. It is up to the user to load the operating system FIRMWARE onto the flash RAM. This in essence makes the hardware legal, since it does not contain any copyrighted information, however some would argue that under the DMCA it still would remain illegal in the USA, due to its ability to assist the circumvention of copyright protections.
A GameCube modchip called Viper was released in December of 2004. It uses the above method of not including offending copyrighted BIOS code. It has some on-board memory which lets the user upload small programs to it. There is also a special program called Cobra that allows use of mini DVD and, if you remove the top casing of your GameCube, full-size DVD media. Previously the only common way to run user code on the GameCube was to use a BBA combined with a security hole in Phantasy Star Online. The Cobra software works, after an original disc is authenticated, by resetting the disc drive and unlocking a debug mode which allows code to be sent to the drive and executed. This code stops the disc drive for a few seconds, allowing the user to swap in a non-original disc.
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Last updated: 08-05-2005 07:42:54
