The Game Genie is a series of cheat cartridges designed by Codemasters and sold by Camerica and Galoob for the Nintendo Entertainment System, Super Nintendo Entertainment System, Game Boy, Mega Drive/Genesis, and Sega Game Gear that modifies game data, allowing the player to cheat, manipulate various aspects of games, and sometimes view unused content and functions. Although there are currently no Game Genie products on the market, most video game console emulators feature Game Genie support. Also, emulators that have Game Genie support allow a near unlimited amount of codes to be entered whereas the actual products have a much smaller limit that usually tops between 3 and 6 codes. The Action Replay, Code Breaker, and GameShark are similar hacking devices that acted as a spiritual successor on later generation consoles, although they were created by entirely different companies.
Operation and Design
The Game Genie attaches to the end of a cartridge and is then inserted into the cartridge port of the console for which it was designed. The loading mechanism of the NES makes the use of the NES Game Genie awkward, as game cartridges for the NES are inserted into the console, then depressed down into the console. The addition of the Game Genie causes the cartridge to protrude from the console when fully inserted, making the depression impossible. Therefore, the Game Genie was designed in such a way that it did not need to be depressed in order to start the game. However, this design made it very difficult to insert into a newer top-loading NES. An adaptor was made to deal with the problem, but few were requested; today they are hard to find since the stock was liquidated.
Upon starting the console, the player may enter a series of characters referred to as a "code" or several such series that reference addresses in the ROM of the cartridge. Each code contains an integer value that is read by the system in place of the data actually present on the cartridge.
Because they patch the program code of a game, Game Genie codes are sometimes referred to as patch codes. These codes can have a variety of effects. The most popular codes give the player some form of invulnerability, infinite ammunition, level skipping, or other modifications that allow the player to be more powerful than intended by the developers. In rare cases, codes even unlock hidden game features that developers had scrapped and rendered unreachable in normal play. Nonetheless, inputting a random code is as effective as using PEEK and POKE operations randomly. The results can yield a useful code, but will most likely result in anything from a mundane or highly unnoticeable change to freezing the game and possibly corrupting saved data. The Game Genie was usually sold with a small booklet of discovered codes for use with the system. However, these booklets would eventually become inadequate as new codes were discovered and new games were released that were not covered. To address this, an update system was implemented, where subscribers would receive quarterly booklet updates for a fee. In addition Galoob also ran ads in certain gaming publications (such as GamePro) that featured codes for newer games. Today, these codes and many others discovered by players can be found for free online.
The Game Genie does not work with Super Nintendo games that contain a performance enhancing chip (e.g. Super FX and S-DD1 chip) such as Star Fox, Super Mario World 2: Yoshi's Island, and Street Fighter Alpha 2. These game cartridges contain additional pins that insert into the slots located left and right of the main center slot. Cartridge adapters made before the release of Star Fox (the first game to need the expansion slots) like the Game Genie did not have a connection to these previously unused slots, so cartridges that contain an additional processor (and thus need to be connected to those slots to do I/O with the system) could not be plugged into these devices. However, some games with these extra contacts worked perfectly nonetheless, most notably Mega Man X2 and Mega Man X3.
On the Sega Mega Drive/Sega Genesis, the Game Genie can function as a country converter cartridge since most of these games are only "locked" to their respective regions by the shape of the cartridges and a set of a few bytes in the header of the ROM.
Because it bypasses the lock-out chip, the NES version of the Game Genie allows the user to play games from other countries (excluding Japan, whose Famicom games have a 60-pin connector, as opposed to the 72-pin NES cartridges).
The SNES version of the Game Genie can also allow the user to play games from other countries (such as European games and Super Famicom games) because the Game Genie also bypasses the lockout chip like the NES version.
The Sega Game Gear's game genie had a very interesting design. When inserted into the cartridge slot, another slot would pop-up to insert the Game Gear cartridge. It also had a compartment which contained a book of codes. The codes were printed on sticky labels to put on the back of the Game Gear cartridge. When entering codes, the player could easily see what to type in rather than looking through the book.
The Game Genie's innovations are covered by US Patent #5112051, "Interfacing device for a computer games system", filed May 30, 1990.
The introduction of the original NES Game Genie was met by fierce opposition from Nintendo. Nintendo sued Galoob in the case Lewis Galoob Toys, Inc. v. Nintendo of America, Inc., claiming that the Game Genie created derivative works in violation of copyright law. Sales of the Game Genie initially stopped in the U.S., but not in Canada. In many gaming magazines of the time, Camerica placed Game Genie ads saying "Thank You Canada!" However, after the courts found that use of the Game Genie did not result in a derivative work, Nintendo could do nothing to stop the Game Genie from being sold in the U.S. Sega, on the other hand, fully endorsed the product with their official seal of approval.
Distribution in the U.K.
Distribution of the Game Genie product in the UK was handled by Hornby Hobbies, usually associated with model railways and the Scalextric brand. Working closely with Codemasters they were also responsible for setting up a dedicated telephone helpline to cater for the ever increasing need for newer codes required to cheat/enhance the latest games. This service was manned by the Game Genie Guru of the early 90s, Mark Stoneham, who also regularly featured in console magazines listing his latest collection of up-to-date codes and making the odd guest appearance on Channel 4's Gamesmaster and Sky's Games World.
Little Known Facts
Around the time of the lawsuit with Galoob, Nintendo used other methods in attempts to thwart the Game Genie. Nintendo had made minor modifications to the NES and SNES systems that caused many games not to work with the Game Genie, with the addition of a lock-out chip designed to prevent other companies from making games for the NES without paying fees. This was done with little publicity. The only way one could tell is by the manufacture date or serial number. This is not to be confused with the later redesign of top-loading consoles for the NES and the smaller, sleeker SNES. Nowadays, using emulators to play these games as ROM dumps on the computer with a software Game Genie will work as the pre-Game Genie consoles did.
the above text taken from Wikipedia
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