emulator: "SM2-Emu"
type: libretro
core_classification: community_fork
source: "https://github.com/Zer0one/sm2-emu-libretro"
upstream: "https://github.com/dmanlfc/sm2-emu"
profiled_date: "2026-11-09"
source_commit: "6b282b94e781e20b2b6d522d0dcef5974b7a5d84"
upstream_commit: "8bb80c157b294c1229bd8c1054d13f87daab52c0"
core_version: "0.9.56.1"
version_basis:
  kind: file
  path: "src/libretro/core.cpp"
  pattern: '\{"SM2-Emu", "([^"]+)"'
display_name: "Sega - Model 2 (SM2-Emu Libretro)"
cores:
  - "sm2"
systems:
  - sega-model2

notes: |
  A libretro port of dmanlfc's SM2-Emu, a Sega Model 2 emulator. The port
  shares dmanlfc's history up to 8b3a468 (2026-09-09) and has taken later
  upstream releases by hand, up to 0.9.56.
  ref: src/libretro/core.cpp:956-959

  The game list is games.xml, read from <system>/sm2-emu/. The core refuses
  to load any game without it. It names every set, its parent and device
  sets, the chips of each region and their CRC32. The content is a MAME set
  in .zip or .7z. Its chips are matched by CRC32, or by name when the ROM CRC
  Verification core option is off. A clone also reads its parent beside the
  content.
  ref: src/libretro/core.cpp:634-641, src/libretro/core.cpp:977-1001,
       src/rom/rom_loader.cpp:195-206, src/rom/rom_loader.cpp:765-781,
       src/libretro/core_options.h:196-202

  Daytona USA, its clones and Desert Tank name the model1io device set, Virtua
  Cop and its clone model1io2. The device archive is looked for in
  <system>/sm2-emu/ and then beside the content, and its chips win over the
  copies a game set carries. A game set that holds the I/O board ROM runs
  without the device archive.
  ref: data/games.xml:1004-1010, data/games.xml:1442-1448, data/games.xml:5846-5852,
       src/rom/game_db.cpp:463-475, src/rom/game_db.cpp:813, src/rom/rom_loader.cpp:784-812

  Gun games read custom crosshair images from <system>/sm2-emu/crosshairs/,
  named after the set, its parent or default, with -p1 or -p2 or without.
  They are artwork the user adds, and a built-in crosshair is drawn without
  them.
  ref: src/libretro/core.cpp:1009, src/libretro/crosshair.cpp:137-146

files:
  - name: "games.xml"
    path: "sm2-emu/games.xml"
    system: sega-model2
    required: true
    description: "SM2-Emu game database"
    note: "The data/games.xml of the core's own tree, at the revision of the build. Without it no game loads."
    source_ref: "src/libretro/core.cpp:987-998"

  - name: "model1io.zip"
    path: "sm2-emu/model1io.zip"
    category: bios_zip
    system: sega-model2
    required: true
    description: "Sega Model 1 I/O board device set"
    note: "Named by daytona and desert, and by the daytona clones through their parent. Also read as model1io.7z or beside the content. Those games do not start without the chip, unless their own set carries it."
    source_ref: "data/games.xml:1004-1010, data/games.xml:1027-1029, src/rom/rom_loader.cpp:784-799"
    contents:
      - name: "epr-14869c.25"
        crc32: "24b68e64"

  - name: "model1io2.zip"
    path: "sm2-emu/model1io2.zip"
    category: bios_zip
    system: sega-model2
    required: true
    description: "Sega Model 1 advanced I/O board device set"
    note: "Named by vcop, and by vcopa through its parent. Also read as model1io2.7z or beside the content. Those games do not start without the chip, unless their own set carries it."
    source_ref: "data/games.xml:5846-5852, data/games.xml:5897-5899, src/rom/rom_loader.cpp:784-799"
    contents:
      - name: "epr-17181.6"
        crc32: "1add2b82"