Geolith - RetroBIOS¶
Technical notes
Geolith is a highly accurate Neo Geo AES and MVS emulator using .NEO format ROMs only. BIOS files must be provided as MAME-format ZIP archives in the system directory. The core selects which ZIP to open based on the "geolith_system_type" core option (libretro/libretro.c:1017-1018): - AES mode -> aes.zip - MVS mode -> neogeo.zip - Uni mode -> neogeo.zip (loads uni-bios_4_0.rom from it)
Inside the ZIP, specific ROM files are extracted by filename (src/geo.c:162-241): 1. One 68K BIOS ROM, selected by system type + region: - AES Japan: neo-po.bin - AES other: neo-epo.bin - MVS US: sp-u2.sp1 - MVS Japan: japan-j3.bin - MVS Asia: sp-45.sp1 - MVS Europe: sp-s2.sp1 - Universe: uni-bios_4_0.rom 2. 000-lo.lo (zoom lookup table, always required) 3. sfix.sfix (FIX layer tiles, required for MVS/Uni, not AES) 4. sm1.sm1 (Z80 sound BIOS, required for MVS/Uni, not AES)
The AES mode only needs the 68K BIOS + 000-lo.lo. MVS and Universe BIOS modes additionally need sfix.sfix and sm1.sm1.
11 files | 6 required, 5 optional | 11 in repo, 0 missing
sp-u2.sp1 required in repo in neogeo.zip
- System: snk-neogeo-mvs
- Size: 128.0 KB
- CRC32:
e72943de - Source:
src/geo.c:174 - MVS USA ver. 5 (2 slot) - default for US region
japan-j3.bin optional in repo in neogeo.zip
- System: snk-neogeo-mvs
- Size: 128.0 KB
- CRC32:
dff6d41f - Source:
src/geo.c:177 - MVS Japan (J3) - default for JP region
sp-45.sp1 optional in repo in neogeo.zip
- System: snk-neogeo-mvs
- Size: 512.0 KB
- CRC32:
03cc9f6a - Source:
src/geo.c:180 - NEO-MVH MV1C (Asia) - default for AS region
sp-s2.sp1 optional in repo in neogeo.zip
- System: snk-neogeo-mvs
- Size: 128.0 KB
- CRC32:
9036d879 - Source:
src/geo.c:183 - MVS Asia/Europe ver. 5 (1 slot) - default for EU region
uni-bios_4_0.rom optional in repo in neogeo.zip
- System: snk-neogeo-mvs
- Size: 128.0 KB
- CRC32:
a7aab458 - Source:
src/geo.c:189 - Universe BIOS ver. 4.0 - only version supported by Geolith
000-lo.lo required in repo in neogeo.zip
sfix.sfix required in repo in neogeo.zip
- System: snk-neogeo-mvs
- Size: 128.0 KB
- CRC32:
c2ea0cfd - Source:
src/geo.c:218-219 - System FIX layer tiles (text layer)
sm1.sm1 required in repo in neogeo.zip
- System: snk-neogeo-mvs
- Size: 128.0 KB
- CRC32:
94416d67 - Source:
src/geo.c:229-230 - Z80 sound BIOS
neo-epo.bin required in repo in aes.zip
- System: snk-neogeo-aes
- Size: 128.0 KB
- CRC32:
d27a71f1 - Source:
src/geo.c:168 - AES Asia/US/EU - default for non-JP regions
neo-po.bin optional in repo in aes.zip
- System: snk-neogeo-aes
- Size: 128.0 KB
- CRC32:
16d0c132 - Source:
src/geo.c:167-168 - AES Japan - default for JP region
000-lo.lo required in repo in aes.zip
Generated on 2026-04-18T08:05:07Z