GameShark Pro

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 either for specific values or for values that have changed in a specific way (increased, decreased, not changed, etc) since the last search. After the first search, subsequent searches only look at memory locations that matched the specified criteria last time. 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. Once the correct location is found, an appropriate value must be chosen, and a code can be put in

In some games the resulting code may only work in one level or may cause problems in other parts of the game due to memory locations being dynamically assigned. In these cases, the user has two options to make a code that does not have these problems: attempt to locate a pointer to the data block that their code is attempting to modify, or change the game's programming which is usually located at the same place every time. If a pointer is found and the device supports it, a new code can be made which determines the correct location to modify from the pointer. If the device does not support pointers, the game programming must be changed instead. Generally the user must use external tools to find the code that accesses this data. If the code is reading from memory, it may be changed to read a constant value; if it is writing, it may be changed to not perform the write. These changes may not have the same effects as actually modifying memory. (For example, you may disable the routine that causes you to lose health when touched by enemies, only to find that health is still lost from other hazards.)

Changing the game program also allows for interesting or unusual effects that would not be possible through other means, such as enabling debug features or changing the way an object behaves. Although the Gameshark is sometimes involved in this process, none to date have provided official tools to assist in it.

Nintendo 64 GameShark Pro

One of the many Gameshark products was the one for the Nintendo 64. The Nintendo 64 GameShark was the most popular cheating device available for the system, becoming popular after well-known titles such as "GoldenEye 007" and "" were released. Because of the in-depth nature of these games, it allowed for many aspects of them to be modified to produce unique effects; for example, much unused content was discovered, such as a distant tower on the "Dam" level of "GoldenEye 007".

The Nintendo 64 Gameshark Pro featured an in-game code search menu. Version 3.3 also had a parallel port on the back, allowing the device to be connected to a PC. This was intended primarily to make entering large amounts of codes easier, but was also used for advanced hacking. The in-game code search required that an Expansion Pak be installed and that the game not be using it.

The Gameshark Pro had several advantages to earlier devices, such as being able to use hundreds of codes at once and save thousands of codes in the Gameshark cartridge. Previous devices, such as the Game Genie, supported as few as 3 codes at a time and had no save function.

Unfortunately, the device was well-known for having numerous flaws. Physically, it was poorly constructed, lacking a proper cartridge holder which made it very unstable. It was also made from low-grade plastic and cheap components, which made it easily breakable. In addition, the software had numerous bugs. Updating the code list would frequently corrupt other parts of the list or the software itself, rendering the device unusable until it was connected to a PC and reformatted, if it was still able to even start up. It also often failed to remember which codes were selected between sessions, and had no protection against power failures - if the power was lost while the code list or software was being updated, the device was very likely to be rendered useless.

ee also

* Game Shark
* Action Replay
* Equalizer (Cheat Code Cartridge)
* Game Genie