Fix MAME BIOS, parent, or CHD errors after a romset update on Android
Treat an emulator update as a definition change. Record the new MAME revision, run its audit for one authorized short name, and follow the exact missing BIOS, parent, device, ROM, or CHD names it reports. Keep CHDs unzipped in the required short-name directory and do not repair a version mismatch by renaming archives or collecting a generic BIOS pack.
Do this in order
- 01
Record the Android port, its exact upstream MAME revision, the game short name, and hashes or receipts for every authorized source file.
- 02
Run that build's audit or `-verifyroms` for one game and preserve the complete first missing or incorrect item list.
- 03
Classify each finding as game ROM, parent/clone dependency, BIOS set, device set, or CHD instead of copying unrelated archives.
- 04
Use the same build's `-listxml` or `-listroms` output to confirm names and relationships; never infer them from a web filename.
- 05
Keep ROM archives named for that build and CHDs unzipped under the expected short-name folder, then verify that the Android storage grant reaches both layers.
- 06
Re-audit before launch and record remaining boot, black-screen, sound, input, and speed behavior as runtime results, not file-permission conclusions.
Decision and diagnostic table
| Audit finding | What changed | Correct next action |
|---|---|---|
| Parent ROM missing | Clone depends on shared parent data | Supply the authorized matching parent set |
| BIOS/device ROM missing | Shared platform definition is separate | Resolve the exact named set lawfully |
| CHD not found | Disk path or short-name folder boundary | Keep verified CHD unzipped in expected folder |
| Wrong length or checksum | Bytes do not match this build | Return to source receipt; never rename as repair |
A romset update changes the question
Parent, clone, BIOS, device, and disk relationships are facts in a particular MAME build. An archive that satisfied an older revision can fail a newer audit even when its filename is unchanged.
ROM archives and CHDs use different layout rules
ROM chip data is commonly stored in named archives. CHDs are already compressed random-access containers and belong unzipped in the directory expected for the machine or software item. A correct CHD cannot compensate for a missing BIOS or parent ROM.
Android access is another gate
A technically complete collection can still be invisible to a wrapper that lacks a retained document grant or maps paths differently. Prove build identity, file identity, dependency layout, and readable storage separately.
Use only ROM, BIOS, device, CHD, artwork, audio, and other media you created, dumped lawfully, or received under permission covering your use. Technical identity, a working emulator, and a published hash do not grant content rights.