The Sega CD Backup RAM Cart is a utility that holds 16 times more game information memory than the internal RAM memory of the Sega CD (with its storage size being 1 Mbit total), which is useful for long-playing games and for not having to start over at the beginning every time the player(s) starts a game. It retailed for $60 U. S. upon initial release.
Before initial use, the Cart has to be formatted, although this is instantaneous with just a press of a button on the Genesis controller during the menu screen, no waiting or any further actions would need to be taken by the user after that. The unit could be formatted again if the user wished, but any game information stored on the Cart would be erased.
The unit plugs into the Sega Genesis cartridge slot (as it resembles a Genesis cart) before the power of the Genesis and the Sega CD is turned on in order for it to be able to start saving game information.
At the absolute maximum, the Cart can hold memory of up to 10 games, as opposed to the Sega CD's capacity of only four. However, some games require multiple save slots, taking up more room on the Cart than others.
The Cart doesn't have many other functions or actions to be taken other than storing game information and formatting the unit. On the onscreen menu, data from the Cart can be viewed, erased, and/or copied to the internal Sega CD memory, or vice versa.
There have been reports of some games not working with restoring their save states, even if they supposedly have them built into the games, such as with Panic!However, some of these cases might have been glitches in regards to the games themselves, rather than this Cart or the Sega CD internal RAM memory being to blame.
Some games also do not even have save states in the first place, such as Night Trap, Tomcat Alley, The Terminator and Sol-Feace, among several others. So this Cart has no use for games such as those. On the flip side, though, reportedly a hidden area of Shining Force CD can not be accessed without this unit.
Care of unit
The usual rules of a cartridge for any kind of game system applies to this Cart, such as not taking the cartridge apart, getting it wet, have it exposed to severe heat or cold, etc. Save files are held in a battery backup SRAM, which means that when the battery runs out your save files will be lost. The battery is a common CR2450 and can be replaced. Contrary to popular belief, occasionally powering on the console does not help in restoring battery life to the Backup Ram Cart.