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BigPEmu
Type standalone
Source https://www.richwhitehouse.com/jaguar/
Version 1.221
Profiled 2026-10-20
Profile YAML, JSON
Cores bigpemu
Systems atari-jaguar, atari-jaguarcd
Technical notes

Closed-source Atari Jaguar and Jaguar CD emulator by Rich Whitehouse. Read from the Linux x64 binary of BigPEmu_Linux64_v1221.tar.gz (sha1 11e8188481ec3dd6508f2497fb35c6ae15907975, from the author's builds page), decompiled with Ghidra at its default image base of 0x100000. The Windows archive BigPEmu_v1221.zip (sha1 879cf1c2ecb426a066703b742f626e14f37d683e) carries the same settings and strings.

Both firmware images are optional settings, BootROM and CDBIOS, each holding a path the user picks in the menu (Boot ROM Image, CD BIOS Image). Nothing is searched by name. A set path is read whole into memory when an image is booted, through the same reader that loads software images, which also accepts a zip. No size is checked. ref: bigpemu FUN_006d8be0 (BootROM and CDBIOS read at boot), FUN_006f4e20 (setting path to buffer), FUN_007d7e20 (image reader), FUN_00762210 and FUN_00761d50 (CDBIOS path setting and browser)

Without a boot ROM a cartridge runs from its own entry point. Without a CD BIOS a disc boots on three replacement blocks decompressed from the executable, 4 KB, 8 KB and 4 KB. The CD BIOS is read only when a disc is mounted. Audio discs refuse to load without one, and the System Audio virtual disc asks for one. ref: bigpemu FUN_006d8be0 (embedded CD boot blocks), FUN_0075f5a0 (STR_AUDIO_CD_NO_BIOS), FUN_00762550 (STR_VDISC_NEEDBIOS)

EEPROM and memory track files are written by the emulator itself, named game<hash>_eeprom.bigpeep and game<hash>_memtrack.bigpmt, beside the image or in user data. Scripts, screen effects, VR lenses and cheat_codes.json ship in the archive. ref: bigpemu FUN_007d55b0, FUN_007d5690

2 files | 0 required, 2 optional | 2 in repo, 0 missing

[BIOS] Atari Jaguar (World).j64 optional in repo #
Jaguar cartridge boot ROM, read when the Boot ROM Image setting is set

[BIOS] Atari Jaguar CD (World).j64 optional in repo #
Jaguar CD BIOS, read when the CD BIOS Image setting is set and a disc is mounted

  • System: atari-jaguarcd
  • Source: bigpemu FUN_006d8be0, FUN_006a8ae0, FUN_0075f5a0
  • Collection copy: bios/Atari/Jaguar/[BIOS] Atari Jaguar CD (World).j64
  • Config key: CDBIOS
  • Any image is used. The retail CD BIOS is recognised by the 64-bit FNV-1a of its first 16384 bytes, 0x7000d38f77b6d407, which installs a dedicated handler set for it. Needed to play audio discs.

Generated on 2026-10-20T03:49:41Z