MAME is constantly updated to improve emulation accuracy. When a developer finds a better "dump" of an arcade chip, the software code is updated to expect that new file. If you use an old ROM file with a newer version of MAME, the emulator will report missing or incorrect files and the game will not launch. Understanding MAME & all the different versions
Because ROMs (including BIOS files) are often copyrighted, complete reference sets are not distributed legally in most countries. Users typically: mame reference set
To use a reference set in MAME:
This request returns a JSON response containing a list of all games in the reference set. MAME is constantly updated to improve emulation accuracy