libretro/emulators/pizza-boy-gbc.yml

emulator: "Pizza Boy GBC"
type: standalone
core_classification: embedded_hle
source: "https://play.google.com/store/apps/details?id=it.dbtecno.pizzaboypro"
upstream: closed-source
author: "Pizza Emulators"
profiled_date: "2026-08-12"
core_version: "6.0.6"
display_name: "Nintendo - Game Boy / Color (Pizza Boy GBC)"
mode: standalone
cores:
  - "pizza-boy-gbc"
  - "Pizza Boy GBC"
  - "PIZZA-BOY-GBC"
systems:
  - nintendo-gb
  - nintendo-gbc
  - nintendo-sgb

notes: |
  Two Android packages, closed source, sold and given away on Google Play under the
  Pizza Boy C name, reached by ES-DE through its PIZZA-BOY-GBC find rule and started
  with the game passed as the rom_uri extra: it.dbtecno.pizzaboypro, the paid build the
  rule names first, and it.dbtecno.pizzaboy, the free one. Two Play distribution builds
  are read here, both carrying the developer certificate sha256
  b3ee584096acf4667bb9346daa9cce19237ef7ce95c99e9260ac89be0f7d6130 (CN=Davide Berra,
  O=DBTecno) and a source stamp: Pro 6.0.6 (versionCode 231), which supplies the Java
  and the resources, and Basic 4.1.6 (versionCode 202), whose arm64-v8a
  libpizzaboy-jni.so ships DWARF and an unstripped symbol table and supplies every
  native reference below as its own file and line. Java line numbers are those of Pro
  6.0.6. The Pro on the store is 7.4.5 (versionCode 324) and no genuine copy of it is
  reachable: apkcombo bounces the download page of a paid app back to the app page,
  apkvision carries no copy, and archive.org holds 6.0.6 alone. The Pro ships its core
  as a stripped armeabi-v7a build. It carries the same log strings and the same
  constants as the Basic core, the 64 KB clear, the 8192 byte read cap, the 256 byte
  header copy and the 256 and 2304 byte gate, and 65 of the 70 entry points it exports
  are exported by the Basic core as well. The Pro also ships libpizza-jni.so, an
  older core exporting the free package JNI names and carrying no BIOS entry point,
  which no loadLibrary call reaches.

  Three systems are emulated from one tree named pizzaboy, whose compilation units
  carry gameboy.c, mmu.c, sgb.c and camera.c: Game Boy, Game Boy Color and Super Game
  Boy. The SGB command set, borders and palettes are handled by sgb.c behind a Super
  Game Boy switch that is on by default, with a preference that gives Game Boy Color
  precedence over Super Game Boy on a cartridge that offers both. camera.c drives the
  Game Boy Camera cartridge from the device camera, and the Game Boy Printer is served
  over the link port.

  The boot ROM is the one file the user supplies, in two slots, Gameboy Classic ROMs
  BIOS and Gameboy Color ROMs BIOS, and it is read only while Load BIOS file is on,
  off by default (res/xml/pref_general.xml:89-99). In the free package the same three
  preferences are declared android:enabled="false" behind a paid badge. A ROM whose
  name ends in .gb or .sgb takes the first slot, every other name takes the second.

  The library never examines the name, the extension or the content: the byte count of
  the read decides the machine. A file of 256 bytes runs the cartridge as a Game Boy,
  one of 2304 bytes as a Game Boy Color, and any other length is refused with "Unknown
  BIOS file", after which the run continues with the boot skipped. The image is read
  into a second MMU whose 0x100 to 0x1FF window is overwritten with the cartridge
  header from the active one, the program counter starts at 0 instead of at the
  cartridge entry, and the animation runs until it reaches 0x100, at which point the
  active MMU returns to the cartridge and the accumulator is restored. A multiplayer
  session exchanges the CRC32 of the Game Boy slot so that both peers run the same
  file.

  Everything else the app opens it makes itself: the default skins and the cheat
  descriptors are raw resources unpacked at first run, the box art, cheat, sticker,
  layout and per-ROM databases are created by their own CREATE TABLE, and the save
  states, the RTC files, the screenshots and the GIF captures are outputs. No boot ROM
  is compiled into the library: neither Game Boy image nor the Nintendo logo appears
  anywhere in the loaded sections, and the post-boot register state comes from the
  reset path instead.

files:
  - name: dmg_boot.bin
    system: nintendo-gb
    required: false
    hle_fallback: true
    agnostic: true
    size: 256
    validation: [size]
    config_key: "bios_file"
    description: "Game Boy (DMG) boot ROM"
    note: >-
      Chosen from any location under any name through the document picker and copied
      into the application directory under the name the picker reports. The legacy
      browser offers .gbc, .gb, .bin and .zip and writes the entry it extracts from a
      zip to bios.bin. The absolute path is stored and handed to the library, which
      copies it into a 256 byte buffer. It is used when the ROM name ends in .gb or
      .sgb, and only on the first run of that ROM and with no multiplayer peer
      connected. The file is read into a second MMU image, up to 8192 bytes, and a
      count of exactly 256 starts the run as a Game Boy, keeping the default palette.
      Nothing else is examined: no name, size range, header or hash test exists on
      either side of the bridge, and a count that is neither 256 nor 2304 is refused.
      A multiplayer session exchanges the CRC32 of this file so that both peers run
      the same one.
    source_ref: "Pizza Boy GBC Pro 6.0.6 MainActivity.java:702 (native method),
      :8067-8081 (gate and slot selection), :1734-1757 (CRC32 of the file),
      :1907, :2136 (multiplayer handshake), SettingsActivity.java:40-41 (request
      codes), :96-113 (picker result and copy), :116-192 (both preferences),
      Common.java:42 (copy to the application directory), FileDialog.java:949-975
      (legacy browser, zip entry to bios.bin), res/xml/pref_general.xml:89-99
      (defaults); Pizza Boy C Basic 4.1.6 libpizzaboy-jni.so pizza.c:1023-1024 (path
      into global_bios_file), global.c:28 (char[256]), mmu.c:431-463 (open, 64 KB
      clear, 8192 byte read, cartridge header copy, 256 and 2304 gate, refusal),
      gameboy.c:1161-1168 (conditions and call), :1171, :1238 (failure),
      :1179-1198 (model, MMU switch, program counter at 0, accumulator),
      :1201-1235 (run to 0x100, return to the cartridge)"

  - name: cgb_boot.bin
    system: nintendo-gbc
    required: false
    hle_fallback: true
    agnostic: true
    size: 2304
    validation: [size]
    config_key: "bios_file_cgb"
    description: "Game Boy Color (CGB) boot ROM"
    note: >-
      Same picker, same copy and same handoff as the Game Boy slot, used for every ROM
      whose name does not end in .gb or .sgb. A count of exactly 2304 starts the run as
      a Game Boy Color, which sets the accumulator to 0x11 and keeps the hardware
      palettes instead of reloading the default one. The 0x100 to 0x1FF window of the
      image is overwritten with the cartridge header before execution, which is the
      gap the 2304 byte layout leaves for it.
    source_ref: "Pizza Boy GBC Pro 6.0.6 MainActivity.java:8073-8078 (slot selection),
      SettingsActivity.java:98 (preference key), :158-192 (preference and picker),
      res/xml/pref_general.xml:97-99; Pizza Boy C Basic 4.1.6 libpizzaboy-jni.so
      mmu.c:435-452 (read, header copy, 2304 gate), gameboy.c:1179 (model from the
      return value), :1189-1198 (program counter, accumulator, palette)"