Post count: 1629

The user “Roo” is the expert here, but essentially:

– Every MAME version released supports certain romsets
– A romset is a .zip file with various roms inside, i.e. dumps of the graphics, sounds etc.. within a given game.
– Romsets can change from one version of MAME to another, i.e. a new or improved rom may be added, or one removed.
– So trying to use the 0.160 set of romsets may well not work with an older version of mame, because the contents of the romsets may differ.
– The dat files contain the names of the roms that should exist in each romset, therefore you can build a romset based on one or many other versions.
– The rebuilding process copies out the relevant roms to create new romsets

The most current arcade emualtor on RetroPie is the libretro-fba.