Instead, these re-used designs and ROM data are categorized as a Devicewith the data stored as a Device set. Frequently the arcade manufacturers would reuse pieces of their designs multiple times in order to save on costs and time. Instead, it is stored as a BIOS image for the system itself e. With those basic principles, there are two other kinds of set that will come up in MAME use from time to time.
A complete merged set with the parent and all clones uses less disk space than a split set. We do not recommend this for most users.Ī split set is one where the parent set contains all of the normal data it should, and the clone sets contain only what has changed as compared to the parent set. This is ordinarily very space-inefficient, but is a good way to go if you want to have very few sets and want everything self-contained and easy to work with. A non-merged set is one that contains absolutely everything necessary for a given game to run in one ZIP file. This allows us to do some magic with how we store these ROM sets to save further space. ZIP parent set will result in an error message that there are missing files. This typically comes up as an error message to the user when trying to run a Clone set without having the Parent set handy. All sets that use mostly the same chips e.
As the MAME developers received their third or fourth revision of Pac-Man, with bugfixes and other code changes, they quickly discovered that nearly all of the board and chips were identical to the previously dumped version.Ī given set, usually but not necessarily the most recent bugfixed World revision of a game, will be designated as the parent. For most consoles and handhelds, the individual chips are frequently but not always merged into a single file. For arcade games, a ROM image or file is a copy of all of the data inside a given chip on the arcade motherboard.