Dolphin emulator can now play all GameCube titles

Developers of the Dolphin open source software have adapted the emulator for the Wii and GameCube so that the only game that has not yet run, Star Wars: The Clone Wars, can now be played with Dolphin.

Dolphin 5.0 was able to boot all games from the official GameCube range except for one title: Star Wars: The Clone Wars. That game evaded emulation because of the way it used the Memory Management Unit, or mmu, of the PowerPC processor.

The GameCube and Wii give games access to virtual memory, and as long as the games use the default mappings for Block Address Translations, or bats, as most games do, there’s nothing to worry about. Dolphin can accurately emulate the mmu here. As long as games predictably access memory, Dolphin can, simply by mapping more ram than the GameCube has.

Star Wars: Rogue Squadron 3 has long been an obstacle as the game could switch from a valid memory address to an invalid address in an unpredictable manner over extended read and write sessions. Star Wars: The Clone Wars took that one step further by taking advantage of Block Address Translations’ ability to switch and create its own memory directories.

The way Dolphin predicted memory behavior didn’t work because of this: the software should actually emulate the bats and be able to switch them on and off while the game is running. That’s why the developers have rewritten the mmu and added dynamic bat functionality. They’ve known for some time that this was the way to get Star Wars: The Clone Wars up and running, but until now they haven’t been able to implement dynamic bats without significantly impacting performance. Due to the rewrite, the mmu emulation is now a lot more accurate and some other games would no longer show crashes, the developers say.