RetroArch MAME 2000 Core: ROM Set Compatibility, Supported Features and Frameskip Options

This reference summarizes the official libretro documentation for the MAME 2000 core used in RetroArch. It covers the ROM set the core expects, which frontend features the core supports, and the frameskip options the documentation lists. It is a summary of source material, not a record of hands-on testing.

What MAME 2000 is

MAME 2000 is built on a snapshot of the MAME codebase taken around the year 2000. It is compatible with the MAME 0.37b5 ROM set, the same set used by the popular iMAME4All port. The documentation describes it as the fastest of the libretro cores, but also as having the worst accuracy and compatibility. It states the core should only be used when speed is the utmost concern, and that on any device able to run a later MAME snapshot, FBNeo or even FBA2012, those are better choices for most users.

Supported and unsupported frontend features

The documentation's feature table records which RetroArch frontend features the core supports. The table below reproduces the entries for saves, save states, rewind, core options, controls and disk control.

• Documented feature support:
• - Save states: supported
• - Core options: supported
• - Controls: supported
• - Saves: not supported
• - Rewind: not supported
• - Disk control: not supported

Frameskip core options

The documentation lists three core options related to frameskip. The descriptions below paraphrase the documented behavior for each option.

• Frameskip: default disabled; accepts disabled, auto or threshold. It skips rendering frames to keep audio output in sync when the host cannot run the game at full speed. 'auto' uses the frontend's audio-buffer hint; 'threshold' skips when the audio buffer drops below the percentage configured in the next option.
• Frameskip Threshold (%): default 30; accepts 30, 40, 50 or 60. When Frameskip is set to 'threshold', a frame is skipped whenever the audio output buffer falls below this percentage of full; lower values skip more aggressively.
• Frameskip Interval: default 1; accepts 1 through 9. This is the maximum number of consecutive frames that may be skipped; lower values keep visual updates smoother at the cost of more audio drops when the host is overloaded.

Scope and limitations

The documented accuracy and compatibility trade-off means results vary by game and ROM set; the documentation does not claim broad compatibility beyond the MAME 0.37b5 set. Because saves, rewind and disk control are not supported, any workflow that depends on those frontend features is outside this core's documented scope.