emulator: Geolith
type: libretro
core_classification: official_port
source: "https://github.com/libretro/geolith-libretro"
upstream: "https://gitlab.com/jgemu/geolith"
profiled_date: "2026-03-21"
core_version: "0.3.0"
display_name: "SNK - Neo Geo AES/MVS (Geolith)"
cores:
  - geolith
systems:
  - snk-neogeo-mvs
  - snk-neogeo-aes

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.

files:
  # -----------------------------------------------------------
  # neogeo.zip - MVS and Universe BIOS
  # -----------------------------------------------------------

  # MVS 68K BIOS ROMs (one required per region)
  - name: "sp-u2.sp1"
    archive: neogeo.zip
    system: snk-neogeo-mvs
    required: true
    size: 131072
    crc32: "e72943de"
    note: "MVS USA ver. 5 (2 slot) - default for US region"
    source_ref: "src/geo.c:174"

  - name: "japan-j3.bin"
    archive: neogeo.zip
    system: snk-neogeo-mvs
    required: false
    size: 131072
    crc32: "dff6d41f"
    note: "MVS Japan (J3) - default for JP region"
    source_ref: "src/geo.c:177"

  - name: "sp-45.sp1"
    archive: neogeo.zip
    system: snk-neogeo-mvs
    required: false
    size: 524288
    crc32: "03cc9f6a"
    note: "NEO-MVH MV1C (Asia) - default for AS region"
    source_ref: "src/geo.c:180"

  - name: "sp-s2.sp1"
    archive: neogeo.zip
    system: snk-neogeo-mvs
    required: false
    size: 131072
    crc32: "9036d879"
    note: "MVS Asia/Europe ver. 5 (1 slot) - default for EU region"
    source_ref: "src/geo.c:183"

  # Universe BIOS (loaded from neogeo.zip when system type = uni)
  - name: "uni-bios_4_0.rom"
    archive: neogeo.zip
    system: snk-neogeo-mvs
    required: false
    size: 131072
    crc32: "a7aab458"
    note: "Universe BIOS ver. 4.0 - only version supported by Geolith"
    source_ref: "src/geo.c:189"

  # Shared ROMs (required for MVS and Universe modes)
  - name: "000-lo.lo"
    archive: neogeo.zip
    system: snk-neogeo-mvs
    required: true
    size: 131072
    crc32: "5a86cff2"
    note: "Zoom lookup table (vertical shrink ROM)"
    source_ref: "src/geo.c:207-208"

  - name: "sfix.sfix"
    archive: neogeo.zip
    system: snk-neogeo-mvs
    required: true
    size: 131072
    crc32: "c2ea0cfd"
    note: "System FIX layer tiles (text layer)"
    source_ref: "src/geo.c:218-219"

  - name: "sm1.sm1"
    archive: neogeo.zip
    system: snk-neogeo-mvs
    required: true
    size: 131072
    crc32: "94416d67"
    note: "Z80 sound BIOS"
    source_ref: "src/geo.c:229-230"

  # -----------------------------------------------------------
  # aes.zip - AES (Home Console)
  # -----------------------------------------------------------

  # AES 68K BIOS ROMs (one required per region)
  - name: "neo-epo.bin"
    archive: aes.zip
    system: snk-neogeo-aes
    required: true
    size: 131072
    crc32: "d27a71f1"
    note: "AES Asia/US/EU - default for non-JP regions"
    source_ref: "src/geo.c:168"

  - name: "neo-po.bin"
    archive: aes.zip
    system: snk-neogeo-aes
    required: false
    size: 131072
    crc32: "16d0c132"
    note: "AES Japan - default for JP region"
    source_ref: "src/geo.c:167-168"

  # Shared ROM (always required for AES)
  - name: "000-lo.lo"
    archive: aes.zip
    system: snk-neogeo-aes
    required: true
    size: 131072
    crc32: "5a86cff2"
    note: "Zoom lookup table (same ROM as in neogeo.zip)"
    source_ref: "src/geo.c:207-208"