{ "commit": "d38cd580364b2c788e633b9e51c15e1668f726c0", "count": 1, "generated_at": "2026-11-03T13:36:34Z", "items": [ { "id": "genesis_plus_gx", "profile": { "core_classification": "community_fork", "core_version": "v1.7.4", "cores": [ "genesis_plus_gx", "genesisplusgx", "genplus", "genesisplusgx_ex", "genesis_plus_gx_cart_special", "genesis-plus-gx" ], "display_name": "Sega - MS/GG/MD/CD (Genesis Plus GX)", "emulator": "Genesis Plus GX", "files": [ { "name": "bios_CD_U.bin", "note": "Sega CD (NTSC-U) boot ROM. Loaded for REGION_USA, which get_region sets for every disc whose security byte is neither 0x64 (Europe) nor 0xa1 (Japan) (core/loadrom.c:1065-1078).", "region": [ "north-america", "latin-america" ], "required": true, "source_ref": "source core/loadrom.c:409", "system": "sega-megacd" }, { "name": "bios_CD_E.bin", "note": "Mega CD (PAL) boot ROM. Loaded for REGION_EUROPE, set by security byte 0x64 at 0x20b, the only PAL branch for Australian discs (core/loadrom.c:1065-1069).", "region": [ "europe", "oceania" ], "required": true, "source_ref": "source core/loadrom.c:412", "system": "sega-megacd" }, { "name": "bios_CD_J.bin", "note": "Mega CD (NTSC-J) boot ROM. Loaded for default/Japan region.", "region": [ "japan" ], "required": true, "source_ref": "source core/loadrom.c:415", "system": "sega-megacd" }, { "name": "bios_U.sms", "note": "Master System (NTSC-U) boot ROM. Snail maze game built in. REGION_USA is the default of sms_cart_region_detect for any export header outside the PAL CRC list, so European, Australian and Brazilian cartridges outside that list load it too (core/cart_hw/sms_cart.c:831-874).", "region": [ "north-america", "latin-america", "europe", "oceania" ], "required": false, "source_ref": "source core/loadrom.c:511", "system": "sega-mastersystem" }, { "name": "bios_E.sms", "note": "Master System (PAL) boot ROM. Snail maze / Sonic built in. REGION_EUROPE comes only from CRC lists of Codemasters and PAL-timing games, Brazilian ones included, or the PAL option (core/cart_hw/sms_cart.c:167-171, 245-264, core/loadrom.c:1161-1164).", "required": false, "source_ref": "source core/loadrom.c:514", "system": "sega-mastersystem" }, { "name": "bios_J.sms", "note": "Master System (NTSC-J) boot ROM.", "region": [ "japan" ], "required": false, "source_ref": "source core/loadrom.c:517", "system": "sega-mastersystem" }, { "name": "bios.gg", "note": "Game Gear boot ROM (Majesco 1KB or standard). Shows startup logo.", "required": false, "source_ref": "source core/loadrom.c:480", "system": "sega-gamegear" }, { "name": "bios_MD.bin", "note": "Mega Drive TMSS boot ROM. Shows 'Produced by or under license' screen.", "required": false, "source_ref": "source libretro/libretro.c:3780", "system": "sega-megadrive" }, { "name": "ggenie.bin", "note": "Game Genie ROM. Loaded when Game Genie lock-on is enabled.", "required": false, "source_ref": "source core/cart_hw/ggenie.c:64, source libretro/libretro.c:3516", "system": "sega-megadrive" }, { "name": "areplay.bin", "note": "Action Replay (Pro) ROM. Loaded when Action Replay lock-on is enabled.", "required": false, "source_ref": "source core/cart_hw/areplay.c:64, source libretro/libretro.c:3517", "system": "sega-megadrive" }, { "name": "sk.bin", "note": "Sonic & Knuckles ROM. Required for S&K lock-on feature.", "required": false, "size": 2097152, "source_ref": "source core/cart_hw/md_cart.c:867", "system": "sega-megadrive", "validation": [ "size" ] }, { "name": "sk2chip.bin", "note": "Sonic & Knuckles UPMEM ROM. Used by Sonic 2 & Knuckles lock-on.", "required": false, "size": 262144, "source_ref": "source core/cart_hw/md_cart.c:873", "system": "sega-megadrive", "validation": [ "size" ] } ], "notes": "Genesis Plus GX is a Sega 8/16-bit emulator covering SG-1000, Master System,\nGame Gear, Mega Drive/Genesis, and Mega CD/Sega CD.\n\nBIOS loading is handled by load_bios() in core/loadrom.c. The libretro port\nresolves filenames from the system directory in libretro/libretro.c:3516-3527.\n\nMega CD BIOS is required to boot CD images (load fails without it).\nMaster System, Game Gear, and Mega Drive BIOS files are optional boot ROMs\ngated behind the \"genesis_plus_gx_bios\" core option (config.bios).\nLock-on ROMs (Game Genie, Action Replay, Sonic & Knuckles) are optional\nand loaded only when the corresponding lock-on feature is enabled.\n", "platform_details": { "gamegear": { "bios_max_size": 4194304, "note": "Handles 1KB Majesco GG BIOS (mapped to $0000-$03FF) and\nstandard larger BIOS ROMs.\n", "source_ref": "source core/loadrom.c:467-489" }, "mastersystem": { "bios_max_size": 4194304, "note": "BIOS ROM loaded into cart.rom + 0x400000. SEGA mapper assumed\nfor ROMs larger than 48KB, otherwise no mapper.\nRegion selected based on current region_code setting.\n", "source_ref": "source core/loadrom.c:504-527" }, "megacd": { "bootrom_size": 131072, "note": "CD boot ROM region is auto-detected from disc image header.\nHardware model detected from boot ROM string at offset 0x120:\n WONDER-MEGA BOOT -> Wondermega\n WONDERMEGA2 BOOT -> Wondermega M2 / X'Eye\n CDX BOOT ROM -> CDX / Multi-Mega\n", "source_ref": "source core/cd_hw/scd.h:73" }, "megadrive": { "note": "TMSS boot ROM validated by checking \"GENESIS OS\" at offset 0x120.\nOnly loaded when genesis_plus_gx_bios core option is enabled.\n", "source_ref": "source libretro/libretro.c:3648-3666", "tmss_rom_size": 2048 } }, "profiled_date": "2026-03-23", "source": "https://github.com/libretro/Genesis-Plus-GX", "source_commit": "60bee4c724859710ce05672239e5b601ad01382e", "systems": [ "sega-megadrive", "sega-megacd", "sega-mastersystem", "sega-gamegear", "sega-sg1000", "sega-pico" ], "type": "libretro", "upstream": "https://github.com/ekeeke/Genesis-Plus-GX", "upstream_commit": "c7ecd07f0a08db1cdd6871d788476bfac55be638", "version_basis": { "kind": "file", "path": "libretro/libretro.c", "pattern": "info->library_version\\s+=\\s+\"([^\"]+)" } } } ], "kind": "emulators", "schema_version": 1 }