{
  "commit": "d38cd580364b2c788e633b9e51c15e1668f726c0",
  "count": 1,
  "generated_at": "2026-11-03T13:36:34Z",
  "items": [
    {
      "id": "beetle_wswan",
      "profile": {
        "core_classification": "pure_libretro",
        "core_version": "v0.9.35.1",
        "cores": [
          "beetle_wswan",
          "mednafen_wswan",
          "beetle-wswan"
        ],
        "display_name": "Bandai - WonderSwan/Color (Beetle Wonderswan)",
        "emulator": "Beetle WonderSwan (Mednafen WonderSwan)",
        "files": [],
        "notes": "Beetle WonderSwan is a fork of Mednafen's Cygne module for WonderSwan\nand WonderSwan Color emulation via libretro.\n\nNo external BIOS or firmware files are required. The core bypasses the\noriginal boot ROM entirely by hardcoding the initial I/O register state\nin mednafen/wswan/start.inc (a 256-byte table of power-on defaults for\nall hardware registers 0x00-0xFF). On reset, WSwan_MemoryReset() in\nwswan-memory.c zeroes RAM and writes a fixed 8-byte identifier at\n0x75AC, then the CPU starts executing the cartridge directly.\n\nInternal EEPROM owner data (name, birthday, sex, blood type) is\nconfigured through core options (wswan.name, wswan.byear, wswan.bmonth,\nwswan.bday, wswan.sex, wswan.blood) and initialized at boot by\nWSwan_EEPROMInit() without needing a real EEPROM dump.\n\nThe wswan.language core option selects English or Japanese, which is\nreturned via I/O port 0xC8+ as the hardware language flag. This\nreplaces the boot ROM's language selection screen.\n\nThe NEC V30MZ CPU is emulated in software (v30mz.c). Sound DMA,\ncartridge banking, and RTC are all handled internally.\n\nROM extensions: .ws, .wsc, .pc2\n",
        "profiled_date": "2026-03-24",
        "source": "https://github.com/libretro/beetle-wswan-libretro",
        "source_commit": "4b01295838ea89e3f1355bbe4cb5cf98aa6108cd",
        "systems": [
          "bandai-wswan",
          "bandai-wswanc"
        ],
        "type": "libretro",
        "upstream": "https://mednafen.github.io/",
        "version_basis": {
          "kind": "file",
          "path": "libretro.c",
          "pattern": "#define\\s+MEDNAFEN_CORE_VERSION\\s+\"([^\"]+)"
        }
      }
    }
  ],
  "kind": "emulators",
  "schema_version": 1
}