Game Boy Advance flash cartridge

A flash cartridge is one of several cartridges containing flash memory that have been developed for use in video game consoles. These cartridges enable homebrew applications and games to be used. The capacity of the cartridges can range from 64 Mbit up to 8 Gbit (Commercial carts range from 32 Mbit to 256 Mbit). More recent cartridges use external memory cards as memory, in place of onboard memory, such as Compact Flash, Secure Digital, etc. memory cards.

These cartridges remain the best-known way to create and distribute homebrew games for many consoles, such as the Game Boy Advance. (another option in this case being the GBA Movie Player, which can run specially designed homebrew programs but cannot run illicit copies of commercial GBA Game cartridges due to the lack of onboard RAM for fast data access).

Games are written to the cartridge with a device called "linker". Depending on the brand of flash cartridge, the linker either connects to a link port on the console and writes to the cartridge through the console, or connects to a mini-USB slot on the cartridge itself and writes directly to the flash cartridge. These linkers usually connect to a PC through a USB or parallel plug on the other end. Most linkers that connect to a link slot are capable of copying ROM information from commercial software cartridges. Some more recent flash cartridges use digital media cards (SD,MMC,CF, etc.) in which files are placed via a memory card reader.

Recently a number of devices have been released which use popular flash memory cards such as SD and CF for storage. These have proven popular since the development of techniques to run Nintendo DS software from a GBA cartridge, due to the smaller size of DS games and the low price of these cards compared to conventional GBA flash cartridges. Examples of such devices include the M3, R4 and Supercard.

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Wikipedia