



Merged: Clones are merged into the parent romset zip, meaning that more than one game is stored per file. BIOS romsets are also ‘split’ from the game romsets and must be placed in the same folder as the game romset. For example, in a Split set pacman.zip (a clone), will not work without puckman.zip (its parent). In some cases the parent is not the most popular or best working version of the game, however. The parent ROM is often the first or most common variant of a game.

Split: Some ROMS that are considered clones, translations, or bootlegs also require a “parent ROM” to run. BIOS romsets are ‘split’ from the game romsets and must be placed in the same folder as the game romset. Non-merged ROMs: Except for romsets which require a BIOS archive, all romsets can be used standalone because each zip contains all the files needed to run that game, including any files from ‘parent ROMs’. (ClrMamePro users: access through the “Advanced” button in the Rebuild and Scanner menus, then deselect “Separate BIOS sets”.) Four Arcade Romset File Formatsįull Non-merged: All ROMs can be used standalone because each zip contains all the files needed to run that game, including any ROMs from ‘parent’ ROM sets and BIOS sets. This database changes with each MAME release and can be generated by running the MAME executable with the flag -listxml. MAME validates ROM sets by checking the CRCs of individual ROM files within a ROM set against its internal database. For example, MAME 0.37b5 sets are required by the mame2000 core, but will not work correctly with the mame2010 core, which requires MAME 0.139 ROM sets. I will follow mamedev convention and use the term romset to refer to a zip or 7zwith the ROM files for one game.Įach version of an arcade emulator must be used with ROM sets that have the same exact version number. Some resources refer to an individual arcade game as a ROM (like people use to describe a zipped game cartridge ROM, which is actually one ROM file inside the zip) while other resources refer to an individual arcade game as a ROM set or romset. In MAME and FB Alpha parlance, a ZIP file containing each of the ROM files needed to emulate one game is called a “ROM set”. Overview and terminologyĪrcade games are packaged as zip files, most of which are composed of more than one individual ‘ROM’ files. I am making this effort in the interest of science. This thread is my attempt to start a specification for arcade ROM scanning based on the ‘native’ validation method employed by MAME and FB Alpha. MAME’s own validation is characterized below. CRC scanning romset zip and 7z files doesn’t make sense in that context – it’s too different from the ‘native’ validation approach used by MAME. Within any given MAME or FB Alpha ROM set, there could be one of four distinct, totally valid zipped romsets or one of four different, equally valid 7z archives for the same title.
