emulator: ymir
type: standalone + libretro
core_classification: community_fork
source:
  standalone: "https://github.com/StrikerX3/Ymir"
  libretro: "https://github.com/warmenhoven/Ymir/tree/libretro"
upstream: "https://github.com/StrikerX3/Ymir"
profiled_date: "2026-03-26"
core_version:
  standalone: "v0.2.1"
  libretro: "PR#746"
display_name: "Sega - Saturn (Ymir)"
cores:
  - ymir
systems:
  - sega-saturn

notes: |
  Ymir is a Sega Saturn emulator by StrikerX3. The libretro port by
  warmenhoven wraps the shared ymir-core library (PR #746, not yet merged).
  No .info file exists in libretro-core-info.

  Standalone: scans configured directories recursively for files matching
  the expected size. No specific filenames required. Identifies known ROMs
  by XXH128 hash from an internal database (19 IPL variants, 4 CD Block
  versions, 2 ROM carts). Unknown files are accepted if size matches.

  Libretro: searches {system}/sega_101.bin, mpr-17933.bin, saturn_bios.bin
  in order. First file found with exact 512 KiB size wins.

  Batocera standalone: configgen maps IPLROMImages to /userdata/bios,
  CDBlockROMImages to /userdata/roms/saturn/cdb/, ROMCartImages to
  /userdata/roms/saturn.

  No HLE fallback for IPL ROM. CD Block LLE is optional; falls back to
  HLE when disabled or no ROM found. Known CDB versions: 1.04, 1.05, 1.06.

  ROM cartridges: KoF95 and Ultraman shipped with physical ROM carts.
  Auto-detected from game database when loading a disc.

  Addon cartridges: 1M/4M DRAM expansion handled via core option (no files).

  XXH128 hashes used for ROM identification only, not validation.
  All file loading validates size only.

files:
  - name: "sega_101.bin"
    system: sega-saturn
    required: true
    size: 524288
    validation: [size]
    aliases: [mpr-17933.bin, saturn_bios.bin]
    description: "Saturn IPL ROM (BIOS). Any region accepted."
    source_ref:
      standalone: "apps/ymir-sdl3/src/util/rom_loader.cpp:9-22, apps/ymir-sdl3/src/app/rom_manager.cpp:14-56, libs/ymir-core/include/ymir/sys/memory_defs.hpp:9"
      libretro: "libretro.cpp:260-263,534-558"

  - name: "cdb/cdb_rom.bin"
    system: sega-saturn
    required: false
    hle_fallback: true
    size: 65536
    validation: [size]
    description: "SH1 CD Block ROM for low-level CD drive emulation. Scans cdb/ subdirectory for any matching file."
    source_ref:
      standalone: "apps/ymir-sdl3/src/util/rom_loader.cpp:25-38, apps/ymir-sdl3/src/app/rom_manager.cpp:58-93, libs/ymir-core/include/ymir/hw/sh1/sh1_defs.hpp:7"
      libretro: "libretro.cpp:567-591"

  - name: "mpr-18811-mx.ic1"
    system: sega-saturn
    required: false
    category: game_data
    size: 2097152
    validation: [size]
    description: "ROM cartridge for The King of Fighters '95."
    source_ref:
      standalone: "apps/ymir-sdl3/src/app/rom_manager.cpp:96-131, libs/ymir-core/include/ymir/db/rom_cart_db.hpp:19-22"
      libretro: "libretro.cpp:619-620,597-616"

  - name: "mpr-19367-mx.ic1"
    system: sega-saturn
    required: false
    category: game_data
    size: 2097152
    validation: [size]
    description: "ROM cartridge for Ultraman: Hikari no Kyojin Densetsu."
    source_ref:
      standalone: "apps/ymir-sdl3/src/app/rom_manager.cpp:96-131, libs/ymir-core/include/ymir/db/rom_cart_db.hpp:25-28"
      libretro: "libretro.cpp:619,621,597-616"