If you see a game requiring a CHD, it means the original arcade cabinet relied on a hard drive or disc to run.
chdman createcd -i gamecue.cue -o game.chd (for CDs) chdman createhd -i hdd.img -o harddrive.chd (for hard drives) mame roms chd
MAME is a living project. The developers are constantly refining the emulation core If you see a game requiring a CHD,
When you download a "ROM set" for a classic game like Pac-Man or Street Fighter II , you are essentially downloading a collection of files that represent the code and graphics stored on the arcade board’s chips. ROMs are digital copies of the data stored
ROMs are digital copies of the data stored on the of an arcade machine's motherboard.
If a game isn't working, use the "Audit" feature built into most MAME interfaces. This will scan your collection and tell you exactly what is missing. If it says "Missing Disk Image," it means your CHD is either missing, named incorrectly, or in the wrong folder.
For CHD-based games (Naomi, Dreamcast-based arcades, Laserdisc), always use a Non-Merged or Split ROM set. Avoid Merged sets unless you are a command-line expert.