yabause - RetroBIOS

Type	libretro
Classification	Community forks
Source	https://github.com/libretro/yabause
Upstream	https://github.com/Yabause/yabause
Version	v0.9.15
Profiled	2026-03-25
Cores	yabause
Systems	sega-saturn

Technical notes

Yabause is a software-rendered Sega Saturn emulator. Upstream project is dead; libretro port maintained by the community on the master branch of libretro/yabause.

Saturn BIOS search order: 1. {system}/saturn_bios.bin 2. {system}/sega_101.bin 3. {system}/mpr-17933.bin First file found wins. HLE BIOS available via yabause_force_hle_bios core option (reduced compatibility). Multi-disc (m3u) requires real BIOS.

Addon cartridges: 1M/4M RAM expansion via core option (no files needed). ROM cartridge loading, SH1 ROM (CD Block LLE), and MPEG card ROM are standalone-only features disabled in the libretro port.

BIOS loading: libretro.c retro_load_game() lines 1035-1049. Core load: memory.c LoadBios() line 1260, T123Load() memory.h lines 196-264.

3 files | 1 required, 2 optional | 3 in repo, 0 missing | 3 with HLE fallback

saturn_bios.bin required in repo HLE fallback

• System: sega-saturn
• Size: max 512.0 KB
• Validation: max_size
• Source: libretro.c:1035
• Platforms: batocera, emudeck, lakka, recalbox, retroarch, retrobat, retrodeck, retropie, romm
• Primary Saturn BIOS. Any region accepted.

sega_101.bin optional in repo HLE fallback japan

• System: sega-saturn
• Size: max 512.0 KB
• Validation: max_size
• Source: libretro.c:1039
• Platforms: batocera, emudeck, lakka, recalbox, retroarch, retrobat, retrodeck, retropie, romm
• Saturn BIOS v1.01 (Japan). Fallback if saturn_bios.bin missing.

mpr-17933.bin optional in repo HLE fallback north-america, europe

• System: sega-saturn
• Size: max 512.0 KB
• Validation: max_size
• Source: libretro.c:1043
• Platforms: batocera, emudeck, lakka, recalbox, retroarch, retrobat, retrodeck, retropie, romm
• Saturn BIOS (NA/EU). Last fallback.

Generated on 2026-04-03T20:37:39Z