GBDK-4.5.0

Upgrading
If upgrading, please review 4.5.0 section in "Migrating to new GBDK Versions" in the docs.

Build OSes (May alter OS compatibility)

• Changed from building on MacOS 13 to MacOS 15 for 64 bit Intel

Highlights

• Added HRAM variable allocation and example (sm83)
• Added SRAM bank #pragma dataseg DATA_<N> and example (sm83, z80)
• Added zx0 compression support and zx0_decompress() (sm83, z80)
• png2asset:
  • Added logging of conversion arguments to .c and .h output files
  • Added -use_metafile option to load arguments from <inputfile>.meta
• New Examples:
  • Game Boy MBC5 Rumble (@EV3lindaboi)
  • SMS NMI handler
  • MegaDuck Laptop Printer

Other Notable Changes

• See Full Release notes in the online docs
• Library
  • GB/AP/Duck
    • Improved get_bkg_xy_addr(), get_win_xy_addr()
    • Improved performance for banked calls
  • SMS/GG
    • Changed GG "not interrrupt" link port control bit constant from GGEXT_NINIT to GGEXT_NINT
    • Fixed parameter order of set_tile_submap(), set_tile_submap_compat()
    • Fixed tilemap width not set correctly in set_tile_submap_compat()
  • NES: Fixed fill_bkg_rect() screen edge wrap, now calls set_bkg_tile_xy()
• Examples
  • Added MegaDuck and Game Gear support to Game Boy Printer example
  • Fixed Platformer example incorrectly using -keep_duplicate_tiles flag
  • Fixed Text Advanced Dialogue example printing
• Toolchain / Utilities
  • bankpack: Changed Linkerfile output for use with asm .bndry alignment in rom banks
  • gbcompress: added include guards for header file output (@RodrigoCard)
  • png2asset
    • Added binary palette export for -bin mode
    • Fixed SGB borders with more than one 16 color palette
• Docs: Improved html style, section links and mobile web formatting

GBDK-4.4.0

Upgrading
If upgrading, please review 4.4.0 section in "Migrating to new GBDK Versions" in the docs.

Build OSes (May alter OS compatibility)

• Changed from building on MacOS 11 to MacOS 13 for 64 bit Intel
• Changed from building on Ubuntu Linux 20.04 to 22.04 for 64 bit Intel

Highlights

• Improved NES support
• Updated compiler to SDCC 4.5.0
• Added Linux ARM 64 build
• New Examples:
  • Game Boy MBC7 Accelerometer, MBC3 Real Time Clock (RTC)
  • Mega Duck Laptop Keyboard, RTC, Speech
• Added makenes utility for finalizing NES rom headers (called automatically by lcc)

Other Notable Changes

• See Full Release notes in the online docs
• Library improvements
  • Timer interrupt emulation: add_TIM(), remove_TIM() for NES/SMS/GG
  • NES
    • Added delay() and reset()
    • Improved LCD ISR support, palette function code size (smaller)
    • Changed LCD bkg_scroll_y to be relative to the current scanline for higher compatibility with Game Boy SCY_REG and LCD handlers
    • Fixed bugs with set_bkg_1bpp_data() in buffered mode, multiple column attribute updates
    • Fixed bugs with non-multiple-of-2 (/4) map width in set_bkg_submap_attributes()
  • SMS/GG: Improved metasprite Y clipping, 16 bit coordinates for ...metasprite...() functions
  • MegaDuck: Added header files: duck/laptop_io.h, duck/model.h, duck/laptop_keycodes.h
• Toolchain / Utilities
  • lcc: Changed use --no-optsdcc-in-asm for building user programs and the GBDK library (avoid SDCC linker issues)
  • png2asset
    • Added support for 512 tiles via alternate tile bank on GBC
    • Fixed Palette Generation broken when using -source_tileset option
  • bankpack: Added support for MBC7, fixed incorrect allocation sizes (@RodrigoCard)
  • romusage
    • Added support NES (-p:NES1) .noi/.map files
  • png2hicolorgb
    • Added -s to specify variable/symbol name in C output
  • Examples
    • Added Text and Dialog example (@LaroldsJubilantJunkyard )
    • Changed irq example to be cross-platform

Pre-release builds of GBDK

For development purposes, not officially supported. May be changed without notice

• Current binaries: 2025-01-16, 4.3.0+ at bc44ef1
• Current binaries: 2025-04-21, 4.4.0 at dd8568b
• Current binaries: 2025-05-19, 4.4.0 at 62de8ab
• Current binaries: 2025-09-21, 4.5.0 at f4f2cec
• Current binaries: 2025-09-21, 4.5.5 (15614) at 113000b
• ~~Current binaries: ~~
  • GBDK: 2025-10-2 at 5aa4559
    • SDCC: with sdcc 4.5.5 (15614) at 1865dbe563f6c64b161e5432ea51c8750153bf04
  • GBDK: 2025-11-23 at 778f233
    • SDCC: with sdcc 4.5.5 (15614) at 1865dbe563f6c64b161e5432ea51c8750153bf04
  • GBDK: 2025-12-19 at 802f092
    • SDCC: with 4.5.0 (15267) + dataseg pragma and sfr patched backported 11d1f650459df85f1011106a7ce65e08222b413f
• Current binaries:
  • 2026-02-04, Post GBDK 4.5.0 at 4a535f5
  • 2026-02-09, Post GBDK 4.5.0 at 2f79d89
  • 2026-02-21, Post GBDK 4.5.0 at 3d03fde on build/gbdk-sdcc-15267-peeprule-18e-off
  • 2026-03-02, Post GBDK 4.5.0 at e3b2f46 on develop
  • 2026-03-08, Post GBDK 4.5.0 at 1e9d73f on develop

GBDK-4.3.0 (Full Release notes)

Release Date: June 8, 2024

Upgrading
If upgrading, please review 4.3.0 section in "Migrating to new GBDK Versions" in the docs.

Highlights

• Improved NES support
• Updated compiler to SDCC 4.4.0
• Added macOS ARM binaries (SDCC building by @chrismaltby)
• New Examples: HBlank copy, Platformer (by @LaroldsJubilantJunkyard), SNES joypads on NES, Game Boy Printer, Joypad test, Display System
• Added romusage utility for estimating used/free ROM and RAM space

Changes

• Library improvements
  • Added get_system() which indicates system speed
  • Changed EMU_printf() to remove dependency on stdio.h added similar EMU_fmtbuf()
  • Fixed emu_debug.h macros missing a trailing space
  • NES
    • Added PAL support
    • Fixed _map_tile_offset for set_bkg_based_tiles(), VRAM transfer buffer bug
    • Fixed support for 4-player controllers using fourscore
  • SMS/GG
    • Added SHOW_SPRITES, HIDE_SPRITES (no hiding mid-frame), DIV_REG emulation, 6 button controller support in joypad()
    • Added bcd.h implementation
    • Added Game Gear registers and definitions
      • GG_STATE, GG_EXT_7BIT, GG_EXT_CTL, GG_SIO_SEND, GG_SIO_RECV, GG_SIO_CTL, GG_SOUND_PAN
    • Changed VDP to reduce chances of dangerous ISR nesting (also for MSX)
    • Fixed tilemap wrapping over the low bound of the VDP name table
    • Fixed waitpad(), scroll_sprite(), __WRITE_VDP_REG_UNSAFE() VDP macro
    • Fixed return result of "set_tile x, y" family functions (also for MSX)
  • Game Boy
    • Added HBlank copy routines: hblank_copy_vram(), hblank_cpy_vram(), hblank_copy()
    • Fixed 8-bit signed modulus
• Toolchain / Utilities
  • lcc: Changed -debug to add the following flags: -Wa-l -Wl-u -Wl-w
  • png2asset
    • Added -sprite_no_optimize, -entity_tileset, -rel_paths
    • Various crashes and output fixes (+ refactor by @LaroldsJubilantJunkyard)
  • makebin: Fixed crash when using -yS (-Wm-yS with lcc)
  • bankpack: Added -banktype= to allow forcing a bank type to CODE or LIT before packing starts
• Examples
  • Wav sample: play waveforms on the SMS/GG PSG
  • Fixes for SMS/GG: Fonts, Large Map, gbdecompress
• Updated documentation and fixed search

gbdk-4.2.0 (Full Release notes)

Upgrading
If upgrading, please review 4.2.0 section in "Migrating to new GBDK Versions" in the docs.

Highlights

• NES support for much of the GBDK API (a big undertaking by @michel-iwaniec)
• Updated compiler to SDCC 4.3 with up to 10% performance/size gains and many fixes
• Game Boy Color Hi-Color conversion utility and display example

Changes

• Library improvements
  • Added set_bkg_attributes(), set_bkg_submap_attributes(), set_bkg_attribute_xy()
  • Some functions renamed (old names will work for now)
    • vsync() replaces wait_vbl_done()
    • set_default_palette() replaces cgb_compatibility()
    • move_metasprite_flipx/y/xy() replace move_metasprite_h/v/hvflip(), move_metasprite_ex() replaces move_metasprite()
  • metasprites: added metasprite functions which can set base sprite property
• NES
  • NES support for much of the GBDK API + banking in the library and toolchain (a big undertaking by @michel-iwaniec)
  • Added set_bkg_attributes_nes16x16(), set_bkg_submap_attributes_nes16x16(), set_bkg_attribute_xy_nes16x16()
• SMS/GG
  • Swapped A and B buttons to match game boy, X coordinate metasprite clipping on the screen edges
• Game Boy:
  • Faster vmemcpy(), set_data(), get_data(), Fixed hide_sprites_range(39u, 40u) overflow shadow OAM
  • Refactored interrupts to use less space
• lccminor fixes
• png2asset: several fixes and a couple new features for palettes
• Added png2hicolorgb + example project
• Examples
  • Improved wav support on AGB/AGS hardware, Added color for Large Map Example, Added GB-Type example
• Updated documentation and improved search

gbdk-4.1.1 is a service release for 4.1.0

• Fixed RGB() and RGB8() macros

For details about gbdk-4.1.0 see the (Full 4.1.0 Release Notes)

gbdk-4.1.0 (Full Release notes)

• Experimental Support for MSXDOS and NES. These are not yet fully functional
• Upgrading: See 4.1.0 section in "Migrating to new GBDK Versions" in the docs for the following.
  • The gbz80 port was renamed to to sm83. Some projects may require updates
  • The default calling convention changed in SDCC 4.2
• Library fixes/improvements
  • SGB: Use longer wait between the SGB packet transfers
  • SMS/GG: less screen artifacts on startup, cgb_compatibility()
  • Fixed: get_sprite_data(), get_bkg_data(), get_win_data() when LCDCF_BG8000 bit of LCDC_REG is set
• Toolchain
  • png2asset: Many new tileset and processing features (See full release notes in docs)
  • lcc: Add -yoA if no ROM size specified with -autobank, Fixed broken -E Preprocess only flag
  • bankpack: Added -reserve=<bank>:<size> to reserve space during packing
  • gbcompress: Bug fixes, added --bank=<num>
  • ihxcheck: Check and warn for bank overflows under specific conditions
  • Added makecom for post-processing msxdos binaries
• Examples: Added APA image 256+ tiles, SGB Sound Effects, new WAV sound example
• Updated documentation

gbdk-4.0.6

• Support for MegaDuck
• Library fixes/improvements
  • fix RNG for SMS/GG
  • check for overflow in metasprites handling routines
  • set_*_based_tiles() / set_*_based_submap() set tilemaps using tile offset
  • add_low_priority_TIM() set timer ISR handler that allows nested interrupts
  • rename gb/BGB_emu.h into gb/EMU_debug.h
  • Intellisense-friendly headers (hide SDCC dialect features)
  • other minor fixes
• Toolchain
  • png2mtspr
    • support for 4bpp graphics and SGB borders
    • new -tile_origin parameter
• Updated documentation

gbdk-4.0.5

• Support for Sega Master System/Sega Game Gear, Analogue Pocket
  • z80 library which provide compatibility layer as well as platform-specific functions
  • support for the new targets on the toolchain side.
  • cross-platform examples (gnu make is required)
  • See Supported Consoles & Cross Compiling for more details
• Library fixes/improvements
  • low level register/constant definitions for all targets
  • DEVICE_* constants
  • BANK* macros
  • some headers were moved from gb/* into gbdk/*
    • bcd.h, console.h, far_ptr.h, font.h, gbdecompress.h, metasprites.h
  • new headers:
    • gbdk/platform.h: includes specific platform headers depending on the target
    • gbdk/incbin.h: INCBIN* macros for including of raw binary data
    • gbdk/rledecompress.h: RLE decompression functions
  • itoa()/uitoa()/ltoa()/ultoa() require radix parameter (GB target ignores it and assumes radix is 10)
  • fixed get_bkg_tile_xy()
  • other minor fixes/enhancements
• Toolchain
  • lcc
    • ability to pass target port/platform
    • support for linker files
  • bankpack
    • support for linker files
    • support for SMS/GG specifics
  • png2mtspr was renamed to png2asset
    • tilemaps/tiledata export without metasprite descriptors
    • CGB support
  • support for RLE compression in gbcompress
• New examples
  • cross-platform examples
  • INCBIN example
  • on-the-fly RLE data decompression example
• Updated documentation

gbdk-4.0.4

• Updated documentation
• Library was improved
  • Switch to standard types declared in stdint.h and stdbool.h
  • Separate cgb.h and sgb.h from gb.h (possible breaking change)
  • get_vram_byte(), get_win_tile_xy(), get_bkg_tile_xy(), set_tile_data()
  • Fix broken decompression to VRAM routines
  • Multiple minor improvements
• png2mtspr improvements and bug fixes
• Support for code relocation with bankpack
• Support for link scripts in lcc
• Support for C input into gbcompress
• Other lcc frontend improvements