Fix a MAME unknown-option error on Android by matching the installed version
Capture the exact `unknown option` message, then identify the Android port's embedded MAME revision and read that build's own help or configuration output. Current online MAME 0.289 documentation describes upstream 0.289, not every Android port. If the installed build does not list the option, remove it or upgrade through the port's official channel; renaming the option or editing unrelated INI files cannot add missing code.
Do this in order
- 01
Preserve the first unknown-option message exactly, including leading dashes, spelling, value, command source, and whether the wrapper inserted or rewrote it.
- 02
Record the Android app version, embedded upstream MAME revision if stated, core version when applicable, build date, architecture, and official source link.
- 03
Open that build's own help, usage, configuration output, or option menu and search for the exact canonical name before consulting rolling online documentation.
- 04
Classify the mismatch as a newer upstream option, a removed or renamed option, a wrapper-only setting, a malformed value, or an INI key in the wrong scope.
- 05
Remove the unsupported line and retest the default launch; upgrade only from the port's official channel when the needed option has a documented compatible release.
- 06
Reintroduce one supported option at a time and retain the version-plus-option receipt so a rollback does not restore incompatible configuration.
Decision and diagnostic table
| Evidence | What it proves | What to do |
|---|---|---|
| 0.289 online manual lists option | Current upstream syntax | Still check installed build |
| Port help omits option | Packaged build cannot expose it there | Remove or use a documented port release |
| Option works in UI, not CLI | Wrapper interface boundary | Use the port's supported surface |
| Error begins after config restore | Version-specific stale key | Quarantine and rebuild configuration incrementally |
The installed binary is the authority
MAME's online manual can move with the current official release and development, while Android ports publish on independent schedules. A search result for an upstream option is evidence about MAME, not proof about an unidentified APK or libretro core.
Wrapper syntax is another layer
Some ports translate UI settings into upstream arguments, accept only a subset, or use their own configuration store. An upstream option can exist in source yet remain unreachable through that wrapper.
A clean default launch isolates the stale option
Preserve the old configuration, remove only the rejected key or test a clean profile, and add back supported settings one at a time. Reinstalling without separating shared configuration may reproduce the same error.
Version diagnosis does not grant rights to ROMs, BIOS files, CHDs, artwork, or music. Share only the option text, version metadata, and redacted logs; do not upload game data or credentials with a configuration report.