genroms is a utility meant to aid in generating ROM files for arcade machines or emulators. You pass it in a standard Intel Hex File (.IHX) along with a description of the ROM layout in memory (.ROMS), and it will generate the ROM files as specified in the ROM layout file. It is primarily meant to help people that are trying to write programs for arcade machines, or for circumstances where the ROM layout may be strange or non-contiguous.