v2026.04.02/emulators/b2.yml

emulator: b2
type: standalone + libretro
core_classification: community_fork
source: "https://github.com/zoltanvb/b2-libretro"
upstream: "https://github.com/tom-seddon/b2"
profiled_date: "2026-03-23"
core_version: "v0.4"
display_name: "Acorn - BBC Micro (b2)"
cores: [b2]
systems:
  - bbc-micro-b
  - bbc-micro-bplus
  - bbc-master-128

notes: |
  Libretro port by Zoltan Balogh of Tom Seddon's b2 BBC Micro emulator.
  is_experimental=true in .info.
  ref: zoltanvb/b2-libretro, tom-seddon/b2

  Standalone loads ROMs from etc/roms/ via GetAssetPath() + LoadFile().
  ref: tom-seddon/b2/src/b2/roms.cpp:9-10

  Libretro port embeds all ROMs as hex arrays in src/libretro/roms.hpp.
  create_core() loads OS and sideways ROMs from static machine_types[] arrays.
  GetAssetPath() and LoadFile() are stubbed — no file I/O at runtime.
  ref: zoltanvb/b2-libretro/src/libretro/roms.hpp
  ref: zoltanvb/b2-libretro/src/libretro/core.cpp:274-304
  ref: zoltanvb/b2-libretro/src/libretro/adapters.cpp:74-78

  9 machine types: B/Acorn 1770, B/Watford DDB2, B/Watford DDB3,
  B/Opus 1770, B/Opus Challenger 256K, B/Opus Challenger 512K,
  B+, B+128, Master 128 (MOS 3.20).
  Master 3.50, Master Turbo, Master Compact not yet implemented.
  ref: zoltanvb/b2-libretro/src/libretro/core.h:117

files: []
# all ROMs embedded in binary via roms.hpp — no external files needed
# .info firmware_count=0 matches code reality