emulator: Beetle PC-FX (Mednafen)
type: libretro
cores: [mednafen_pcfx]
source: "https://github.com/libretro/beetle-pcfx-libretro"
systems:
  - nec-pcfx

notes: |
  Beetle PC-FX is the libretro port of Mednafen's NEC PC-FX emulation module.
  The core requires a single BIOS file: pcfx.rom (1 MB). The setting
  "pcfx.bios" resolves to the filename "pcfx.rom" via MDFN_GetSettingS()
  in mednafen/settings.c:92-93. The file is loaded from the libretro
  system directory in LoadCommon() (libretro.cpp:367-394).

  The BIOS is mapped at address 0xFFF00000 and must be exactly 1048576 bytes
  (1024 * 1024). LoadCommon() returns false if the file is missing or the
  wrong size, so the core will not start without it.

  No other firmware files (fx-scsi.rom, pcfxga.rom, pcfxv101.bin) are
  referenced by this core. Those exist for other PC-FX emulators or
  alternate BIOS versions but are unused here.

  BIOS loading: libretro.cpp LoadCommon() lines 364-397.
  Setting resolution: mednafen/settings.c MDFN_GetSettingS() lines 90-94.
  BIOS memory: static uint8 *BIOSROM, mapped at 0xFFF00000 (1 MB region).

files:
  # -------------------------------------------------------
  # PC-FX BIOS
  # -------------------------------------------------------
  - name: "pcfx.rom"
    system: nec-pcfx
    required: true
    size: 1048576  # 1 MB (1024 * 1024)
    md5: "08e36edbea28a017f79f8d4f7ff9b6d7"
    sha1: "1a77fd83e337f906aecab27a1604db064cf10074"
    note: "PC-FX BIOS v1.00. Only BIOS file used by this core."
    source_ref: "libretro.cpp:367, mednafen/settings.c:92-93"

platform_details:
  pcfx:
    bios_size: 1048576          # 1 MB
    ram_size: 2097152            # 2 MB
    bios_address: "0xFFF00000-0xFFFFFFFF"
    ram_address: "0x00000000-0x001FFFFF"
    cpu: "NEC V810"
    cpu_modes: [accurate, fast]
    hle_available: false
    source_ref: "libretro.cpp:103-104, 379-387"