GameShark

GameShark is the brand name of a line of video game cheat cartridges and other products for a variety of console video game systems and Windows-based computers. Currently, the brand name is owned by Mad Catz, which actively markets GameShark products for the Sony PlayStation, Xbox, and Nintendo game consoles. Players load cheat codes from Gameshark discs or cartridges onto the console's internal or external memory, so that when the game is loaded, the selected cheats can be applied.

When the original GameShark was released, it came with 4,000 preloaded codes. Codes could be entered, but unlike the Game Genie, codes were saved in the onboard flash memory and could be accessed later rather than having to be reentered. The cartridges also acted as memory cards, with equal or greater storage capacity to the consoles' first party memory cards. It was originally released for the Sega Saturn and Sony PlayStation consoles in the Fall of 1995. Models for the PlayStation had an Explorer option that allowed gamers to access most PlayStation disc files, and it was possible to view FMV files stored on the CD. The later models of the GameShark also had a Use Enhancement Disc option. The Enhancement Disc, which InterAct sold for $4.95, allowed users to upgrade the GameShark and add codes to the code list from the disc. Only a few examples of these Upgrade CDs were known to have been published.

The PlayStation Gameshark had the following standard features: View Video Image, which allowed users to see the last image stored in the PlayStation's Video RAM, View CD Image, which allowed a user to search the game CD for image files, Play Music, which would play the CD audio, and View CD Movie, a function that allowed a user to view FMV (full motion video) files found on the disc. Also included was the option to use an Enhancement CD in order to upgrade the Gameshark and add new codes found on the disc.

The Gameshark Pro series contained a feature that allowed players to find their own codes. During gameplay, the user presses a button on the device to open a code search menu. Finding a code is done by searching memory locations either for specific values or for values that have changed in a certain way (increased, decreased, not changed, etc.) since the last search. After the first search, subsequent searches only look at memory locations that match the specified criteria from the last search. By performing multiple searches the list of matching locations is gradually reduced. Once the list is reasonably small the user must determine which of the found locations is the correct one by modifying them one at a time and seeing what effect it has on the game.

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