emulator: Beetle PSX (Mednafen PSX)
type: libretro
core_classification: community_fork
source: "https://github.com/libretro/beetle-psx-libretro"
upstream: "https://mednafen.github.io/"
profiled_date: "2026-03-29"
core_version: "v0.9.44.1"
display_name: "Sony - PlayStation (Beetle PSX)"
cores: [beetle_psx, mednafen_psx, mednafen_psx_hw]
systems: [sony-playstation]
notes: >
  Region-based BIOS selection: the core picks JP/NA/EU firmware based on disc region.
  SHA1 validated with warning on mismatch (does not block loading).
  SHA1 and alternate filenames sourced from MAME psx.cpp (libretro.cpp:186).
  Override option allows using PSP, PS3, or OpenBIOS as region-free alternative.
  Embedded OpenBIOS (512KB) compiled into the binary serves as HLE fallback when no BIOS found.
  "Skip BIOS" option patches BIOS ROM but causes compatibility issues.
  Upstream Mednafen loads the same 3 region BIOS; override BIOS and HLE fallback are libretro additions.

files:
  # -- Region: Japan (REGION_JP) --

  - name: "scph5500.bin"
    description: "SCPH-5500 (v3.0 09-09-96 J)"
    region: "NTSC-J"
    required: true
    hle_fallback: true
    size: 524288
    sha1: "b05def971d8ec59f346f2d9ac21fb742e3eb6917"
    md5: "8dd7d5296a650fac7319bce665a6a53c"
    validation: [sha1]
    mode: both
    source_ref: "libretro.cpp:261-269"
    aliases: ["SCPH5500.bin", "SCPH-5500.bin"]

  # -- Region: North America (REGION_NA) --

  - name: "scph5501.bin"
    description: "SCPH-5501, 5503, 7003 (v3.0 11-18-96 A)"
    region: "NTSC-U"
    required: true
    hle_fallback: true
    size: 524288
    sha1: "0555c6fae8906f3f09baf5988f00e55f88e9f30b"
    md5: "490f666e1afb15b7362b406ed1cea246"
    validation: [sha1]
    mode: both
    source_ref: "libretro.cpp:271-289"
    aliases:
      - "SCPH5501.bin"
      - "SCPH-5501.bin"
      - "scph5503.bin"
      - "SCPH5503.bin"
      - "SCPH-5503.bin"
      - "scph7003.bin"
      - "SCPH7003.bin"
      - "SCPH-7003.bin"

  # -- Region: Europe (REGION_EU) --

  - name: "scph5502.bin"
    description: "SCPH-5502, 5552 (v3.0 01-06-97 E)"
    region: "PAL"
    required: true
    hle_fallback: true
    size: 524288
    sha1: "f6bc2d1f5eb6593de7d089c425ac681d6fffd3f0"
    md5: "32736f17079d0b2b7024407c39bd3050"
    validation: [sha1]
    mode: both
    source_ref: "libretro.cpp:291-305"
    aliases:
      - "SCPH5502.bin"
      - "SCPH-5502.bin"
      - "scph5552.bin"
      - "SCPH5552.bin"
      - "SCPH-5552.bin"

  # -- Override BIOS (region-free alternatives) --

  - name: "psxonpsp660.bin"
    description: "PSP embedded PS1 BIOS (region-free override)"
    region: "Auto"
    required: false
    size: 524288
    sha1: "96880d1ca92a016ff054be5159bb06fe03cb4e14"
    md5: "c53ca5908936d412331790f4426c6c33"
    validation: [sha1]
    mode: libretro
    source_ref: "libretro.cpp:192-198"
    aliases: ["PSXONPSP660.bin"]
    note: "override_bios=1. Falls back to region BIOS if not found."

  - name: "ps1_rom.bin"
    description: "PS3 embedded PS1 BIOS, first 512KB extracted (region-free override)"
    region: "Auto"
    required: false
    sha1: "c40146361eb8cf670b19fdc9759190257803cab7"
    md5: "81bbe60ba7a3d1cea1d48c14cbcc647b"
    validation: [sha1]
    mode: libretro
    source_ref: "libretro.cpp:200-206"
    aliases: ["PS1_ROM.bin"]
    note: "override_bios=2. Falls back to region BIOS if not found."

  - name: "openbios.bin"
    description: "OpenBIOS (open-source PS1 HLE BIOS, region-free override)"
    region: "Auto"
    required: false
    size: 524288
    mode: libretro
    source_ref: "libretro.cpp:208-214"
    aliases: ["OPENBIOS.bin"]
    note: "override_bios=3. No SHA1 validation. Falls back to region BIOS if not found. Also embedded in binary as HLE fallback (libretro.cpp:2157-2159)."