GBDK 2020 Docs  4.1.1
API Documentation for GBDK 2020
Toolchain settings

lcc settings

./lcc [ option | file ]...
except for -l, options are processed left-to-right before files
unrecognized options are taken to be linker options
-A warn about nonANSI usage; 2nd -A warns more
-b emit expression-level profiling code; see bprint(1)
-Bdir/ use the compiler named `dir/rcc'
-c compile only
-dn set switch statement density to `n'
-debug Turns on --debug for compiler, -y (.cdb) and -j (.noi) for linker
-Dname -Dname=def define the preprocessor symbol `name'
-E only run preprocessor on named .c and .h files files -> stdout
--save-preproc Use with -E for output to *.i files instead of stdout
-g produce symbol table information for debuggers
-help or -? print this message
-Idir add `dir' to the beginning of the list of #include directories
-K don't run ihxcheck test on linker ihx output
-lx search library `x'
-m select port and platform: "-m[port]:[plat]" ports:sm83,z80,mos6502 plats:ap,duck,gb,sms,gg,nes
-N do not search the standard directories for #include files
-n emit code to check for dereferencing zero pointers
-no-crt do not auto-include the gbdk crt0.o runtime in linker list
-no-libs do not auto-include the gbdk libs in linker list
-O is ignored
-o file leave the output in `file'
-P print ANSI-style declarations for globals
-p -pg emit profiling code; see prof(1) and gprof(1)
-S compile to assembly language
-autobank auto-assign banks set to 255 (bankpack)
-static specify static libraries (default is dynamic)
-t -tname emit function tracing calls to printf or to `name'
-target name is ignored
-tempdir=dir place temporary files in `dir/'; default=/tmp
-Uname undefine the preprocessor symbol `name'
-v show commands as they are executed; 2nd -v suppresses execution
-w suppress warnings
-Woarg specify system-specific `arg'
-W[pfablim]arg pass `arg' to the preprocessor, compiler, assembler, bankpack, linker, ihxcheck, or makebin

sdcc settings

SDCC : z80/sm83/mos6502 4.2.2 #13350 (Linux)
published under GNU General Public License (GPL)
Usage : sdcc [options] filename
Options :-
General options:
--help Display this help
-v --version Display sdcc's version
--verbose Trace calls to the preprocessor, assembler, and linker
-V Execute verbosely. Show sub commands as they are run
-d Output list of macro definitions in effect. Use with -E
-D Define macro as in -Dmacro
-I Add to the include (*.h) path, as in -Ipath
-A
-U Undefine macro as in -Umacro
-M Preprocessor option
-W Pass through options to the pre-processor (p), assembler (a) or linker (l)
--include Pre-include a file during pre-processing
-S Compile only; do not assemble or link
-c --compile-only Compile and assemble, but do not link
-E --preprocessonly Preprocess only, do not compile
--c1mode Act in c1 mode. The standard input is preprocessed code, the output is assembly code.
-o Place the output into the given path resp. file
-x Optional file type override (c, c-header or none), valid until the next -x
--print-search-dirs display the directories in the compiler's search path
--vc messages are compatible with Micro$oft visual studio
--use-stdout send errors to stdout instead of stderr
--nostdlib Do not include the standard library directory in the search path
--nostdinc Do not include the standard include directory in the search path
--less-pedantic Disable some of the more pedantic warnings
--disable-warning <nnnn> Disable specific warning
--Werror Treat the warnings as errors
--debug Enable debugging symbol output
--cyclomatic Display complexity of compiled functions
--std-c89 Use ISO C90 (aka ANSI C89) standard (slightly incomplete)
--std-sdcc89 Use ISO C90 (aka ANSI C89) standard with SDCC extensions
--std-c95 Use ISO C95 (aka ISO C94) standard (slightly incomplete)
--std-c99 Use ISO C99 standard (incomplete)
--std-sdcc99 Use ISO C99 standard with SDCC extensions
--std-c11 Use ISO C11 standard (incomplete)
--std-sdcc11 Use ISO C11 standard with SDCC extensions (default)
--std-c2x Use ISO C2X standard (incomplete)
--std-sdcc2x Use ISO C2X standard with SDCC extensions
--fdollars-in-identifiers Permit '$' as an identifier character
--fsigned-char Make "char" signed by default
--use-non-free Search / include non-free licensed libraries and header files
Code generation options:
-m Set the port to use e.g. -mz80.
-p Select port specific processor e.g. -mpic14 -p16f84
--stack-auto Stack automatic variables
--xstack Use external stack
--int-long-reent Use reentrant calls on the int and long support functions
--float-reent Use reentrant calls on the float support functions
--xram-movc Use movc instead of movx to read xram (xdata)
--callee-saves <func[,func,...]> Cause the called function to save registers instead of the caller
--fomit-frame-pointer Leave out the frame pointer.
--all-callee-saves callee will always save registers used
--stack-probe insert call to function __stack_probe at each function prologue
--no-xinit-opt don't memcpy initialized xram from code
--no-c-code-in-asm don't include c-code as comments in the asm file
--no-peep-comments don't include peephole optimizer comments
--codeseg <name> use this name for the code segment
--constseg <name> use this name for the const segment
--dataseg <name> use this name for the data segment
Optimization options:
--nooverlay Disable overlaying leaf function auto variables
--nogcse Disable the GCSE optimisation
--nolabelopt Disable label optimisation
--noinvariant Disable optimisation of invariants
--noinduction Disable loop variable induction
--noloopreverse Disable the loop reverse optimisation
--no-peep Disable the peephole assembly file optimisation
--no-reg-params On some ports, disable passing some parameters in registers
--peep-asm Enable peephole optimization on inline assembly
--peep-return Enable peephole optimization for return instructions
--no-peep-return Disable peephole optimization for return instructions
--peep-file <file> use this extra peephole file
--opt-code-speed Optimize for code speed rather than size
--opt-code-size Optimize for code size rather than speed
--max-allocs-per-node Maximum number of register assignments considered at each node of the tree decomposition
--nolospre Disable lospre
--allow-unsafe-read Allow optimizations to read any memory location anytime
--nostdlibcall Disable optimization of calls to standard library
Internal debugging options:
--dump-ast Dump front-end AST before generating i-code
--dump-i-code Dump the i-code structure at all stages
--dump-graphs Dump graphs (control-flow, conflict, etc)
--i-code-in-asm Include i-code as comments in the asm file
--fverbose-asm Include code generator comments in the asm output
Linker options:
-l Include the given library in the link
-L Add the next field to the library search path
--lib-path <path> use this path to search for libraries
--out-fmt-ihx Output in Intel hex format
--out-fmt-s19 Output in S19 hex format
--xram-loc <nnnn> External Ram start location
--xram-size <nnnn> External Ram size
--iram-size <nnnn> Internal Ram size
--xstack-loc <nnnn> External Stack start location
--code-loc <nnnn> Code Segment Location
--code-size <nnnn> Code Segment size
--stack-loc <nnnn> Stack pointer initial value
--data-loc <nnnn> Direct data start location
--idata-loc
--no-optsdcc-in-asm Do not emit .optsdcc in asm
Special options for the z80 port:
--callee-saves-bc Force a called function to always save BC
--portmode= Determine PORT I/O mode (z80/z180)
-bo <num> use code bank <num>
-ba <num> use data bank <num>
--asm= Define assembler name (rgbds/asxxxx/isas/z80asm/gas)
--codeseg <name> use this name for the code segment
--constseg <name> use this name for the const segment
--dataseg <name> use this name for the data segment
--no-std-crt0 Do not link default crt0.rel
--reserve-regs-iy Do not use IY (incompatible with --fomit-frame-pointer)
--fno-omit-frame-pointer Do not omit frame pointer
--emit-externs Emit externs list in generated asm
--legacy-banking Use legacy method to call banked functions
--nmos-z80 Generate workaround for NMOS Z80 when saving IFF2
--sdcccall Set ABI version for default calling convention
--allow-undocumented-instructions Allow use of undocumented instructions
Special options for the sm83 port:
-bo <num> use code bank <num>
-ba <num> use data bank <num>
--asm= Define assembler name (rgbds/asxxxx/isas/z80asm/gas)
--callee-saves-bc Force a called function to always save BC
--codeseg <name> use this name for the code segment
--constseg <name> use this name for the const segment
--dataseg <name> use this name for the data segment
--no-std-crt0 Do not link default crt0.rel
--legacy-banking Use legacy method to call banked functions
--sdcccall Set ABI version for default calling convention
Special options for the mos6502 port:
--model-small 8-bit address space for data
--model-large 16-bit address space for data (default)
--no-std-crt0 Do not link default crt0.rel

sdasgb settings

sdas Assembler V02.00 + NoICE + SDCC mods (GameBoy)
Copyright (C) 2012 Alan R. Baldwin
This program comes with ABSOLUTELY NO WARRANTY.
Usage: [-Options] [-Option with arg] file
Usage: [-Options] [-Option with arg] outfile file1 [file2 ...]
-h or NO ARGUMENTS Show this help list
Input:
-I Add the named directory to the include file
search path. This option may be used more than once.
Directories are searched in the order given.
Output:
-l Create list file/outfile[.lst]
-o Create object file/outfile[.rel]
-s Create symbol file/outfile[.sym]
Listing:
-d Decimal listing
-q Octal listing
-x Hex listing (default)
-b Display .define substitutions in listing
-bb and display without .define substitutions
-c Disable instruction cycle count in listing
-f Flag relocatable references by ` in listing file
-ff Flag relocatable references by mode in listing file
-p Disable automatic listing pagination
-u Disable .list/.nlist processing
-w Wide listing format for symbol table
Assembly:
-v Enable out of range signed / unsigned errors
Symbols:
-a All user symbols made global
-g Undefined symbols made global
-n Don't resolve global assigned value symbols
-z Disable case sensitivity for symbols
Debugging:
-j Enable NoICE Debug Symbols
-y Enable SDCC Debug Symbols

sdasz80 settings

sdas Assembler V02.00 + NoICE + SDCC mods (GameBoy)
Copyright (C) 2012 Alan R. Baldwin
This program comes with ABSOLUTELY NO WARRANTY.
Usage: [-Options] [-Option with arg] file
Usage: [-Options] [-Option with arg] outfile file1 [file2 ...]
-h or NO ARGUMENTS Show this help list
Input:
-I Add the named directory to the include file
search path. This option may be used more than once.
Directories are searched in the order given.
Output:
-l Create list file/outfile[.lst]
-o Create object file/outfile[.rel]
-s Create symbol file/outfile[.sym]
Listing:
-d Decimal listing
-q Octal listing
-x Hex listing (default)
-b Display .define substitutions in listing
-bb and display without .define substitutions
-c Disable instruction cycle count in listing
-f Flag relocatable references by ` in listing file
-ff Flag relocatable references by mode in listing file
-p Disable automatic listing pagination
-u Disable .list/.nlist processing
-w Wide listing format for symbol table
Assembly:
-v Enable out of range signed / unsigned errors
Symbols:
-a All user symbols made global
-g Undefined symbols made global
-n Don't resolve global assigned value symbols
-z Disable case sensitivity for symbols
Debugging:
-j Enable NoICE Debug Symbols
-y Enable SDCC Debug Symbols

bankpack settings

bankalloc [options] objfile1 objfile2 etc
Use: Read .o files and auto-assign areas with bank=255.
Typically called by Lcc compiler driver before linker.
Options
-h : Show this help
-lkin=<file> : Load object files specified in linker file <file>
-lkout=<file> : Write list of object files out to linker file <file>
-yt<mbctype> : Set MBC type per ROM byte 149 in Decimal or Hex (0xNN)
([see pandocs](https://gbdev.io/pandocs/The_Cartridge_Header.html#0147---cartridge-type))
-mbc=N : Similar to -yt, but sets MBC type directly to N instead
of by intepreting ROM byte 149
mbc1 will exclude banks {0x20,0x40,0x60} max=127,
mbc2 max=15, mbc3 max=127, mbc5 max=255 (not 511!)
-min=N : Min assigned ROM bank is N (default 1)
-max=N : Max assigned ROM bank is N, error if exceeded
-ext=<.ext> : Write files out with <.ext> instead of source extension
-path=<path> : Write files out to <path> (<path> *MUST* already exist)
-sym=<prefix> : Add symbols starting with <prefix> to match + update list.
Default entry is "___bank_" (see below)
-cartsize : Print min required cart size as "autocartsize:<NNN>"
-plat=<plat> : Select platform specific behavior (default:gb) (gb,sms)
-random : Distribute banks randomly for testing (honors -min/-max)
-reserve=<b:n>: Reserve N bytes (hex) in bank B (decimal)
Ex: -reserve=105:30F reserves 0x30F bytes in bank 105
-v : Verbose output, show assignments
Example: "bankpack -ext=.rel -path=some/newpath/ file1.o file2.o"
Unless -ext or -path specify otherwise, input files are overwritten.
Default MBC type is not set. It *must* be specified by -mbc= or -yt!
The following will have FF and 255 replaced with the assigned bank:
A _CODE_255 size <size> flags <flags> addr <address>
S b_<function name> Def0000FF
S ___bank_<const name> Def0000FF
(Above can be made by: const void __at(255) __bank_<const name>;

sdldgb settings

sdld Linker V03.00 + NoICE + sdld
Usage: [-Options] [-Option with arg] file
Usage: [-Options] [-Option with arg] outfile file1 [file2 ...]
Startup:
-p Echo commands to stdout (default)
-n No echo of commands to stdout
Alternates to Command Line Input:
-c ASlink >> prompt input
-f file[.lk] Command File input
Libraries:
-k Library path specification, one per -k
-l Library file specification, one per -l
Relocation:
-b area base address = expression
-g global symbol = expression
Map format:
-m Map output generated as (out)file[.map]
-w Wide listing format for map file
-x Hexadecimal (default)
-d Decimal
-q Octal
Output:
-i Intel Hex as (out)file[.ihx]
-s Motorola S Record as (out)file[.s19]
-j NoICE Debug output as (out)file[.noi]
-y SDCDB Debug output as (out)file[.cdb]
List:
-u Update listing file(s) with link data as file(s)[.rst]
Case Sensitivity:
-z Disable Case Sensitivity for Symbols
End:
-e or null line terminates input

sdldz80 settings

sdld Linker V03.00 + NoICE + sdld
Usage: [-Options] [-Option with arg] file
Usage: [-Options] [-Option with arg] outfile file1 [file2 ...]
Startup:
-p Echo commands to stdout (default)
-n No echo of commands to stdout
Alternates to Command Line Input:
-c ASlink >> prompt input
-f file[.lk] Command File input
Libraries:
-k Library path specification, one per -k
-l Library file specification, one per -l
Relocation:
-b area base address = expression
-g global symbol = expression
Map format:
-m Map output generated as (out)file[.map]
-w Wide listing format for map file
-x Hexadecimal (default)
-d Decimal
-q Octal
Output:
-i Intel Hex as (out)file[.ihx]
-s Motorola S Record as (out)file[.s19]
-j NoICE Debug output as (out)file[.noi]
-y SDCDB Debug output as (out)file[.cdb]
List:
-u Update listing file(s) with link data as file(s)[.rst]
Case Sensitivity:
-z Disable Case Sensitivity for Symbols
End:
-e or null line terminates input

ihxcheck settings

ihx_check input_file.ihx [options]
Options
-h : Show this help
-e : Treat warnings as errors
Use: Read a .ihx and warn about overlapped areas.
Example: "ihx_check build/MyProject.ihx"

makebin settings

Also see setting_mbc_and_rom_ram_banks

makebin: convert a Intel IHX file to binary or GameBoy format binary.
Usage: makebin [options] [<in_file> [<out_file>]]
Options:
-p pack mode: the binary file size will be truncated to the last occupied byte
-s romsize size of the binary file (default: rom banks * 16384)
-Z generate GameBoy format binary file
-S generate Sega Master System format binary file
-N generate Famicom/NES format binary file
-o bytes skip amount of bytes in binary file
SMS format options (applicable only with -S option):
-xo n rom size (0xa-0x2) (default: 0xc)
-xj n set region code (3-7) (default: 4)
-xv n version number (0-15) (default: 0)
GameBoy format options (applicable only with -Z option):
-yo n number of rom banks (default: 2) (autosize: A)
-ya n number of ram banks (default: 0)
-yt n MBC type (default: no MBC)
-yl n old licensee code (default: 0x33)
-yk cc new licensee string (default: 00)
-yn name cartridge name (default: none)
-yc GameBoy Color compatible
-yC GameBoy Color only
-ys Super GameBoy
-yS Convert .noi file named like input file to .sym
-yj set non-Japanese region flag
-yN do not copy big N validation logo into ROM header
-yp addr=value Set address in ROM to given value (address 0x100-0x1FE)
Arguments:
<in_file> optional IHX input file, '-' means stdin. (default: stdin)
<out_file> optional output file, '-' means stdout. (default: stdout)

makecom settings

makecom image.rom image.noi output.com
Use: convert a binary .rom file to .msxdos com format.

gbcompress settings

gbcompress [options] infile outfile
Use: compress a binary file and write it out.
Options
-h : Show this help screen
-d : Decompress (default is compress)
-v : Verbose output
--cin : Read input as .c source format (8 bit char ONLY, uses first array found)
--cout : Write output in .c / .h source format (8 bit char ONLY)
--varname=<NAME> : specify variable name for c source output
--alg=<type> : specify compression type: 'rle', 'gb' (default)
--bank=<num> : Add Bank Ref: 1 - 511 (default is none, with --cout only)
Example: "gbcompress binaryfile.bin compressed.bin"
Example: "gbcompress -d compressedfile.bin decompressed.bin"
Example: "gbcompress --alg=rle binaryfile.bin compressed.bin"
The default compression (gb) is the type used by gbtd/gbmb
The rle compression is Amiga IFF style

png2asset settings

usage: png2asset <file>.png [options]
-c ouput file (default: <png file>.c)
-sw <width> metasprites width size (default: png width)
-sh <height> metasprites height size (default: png height)
-sp <props> change default for sprite OAM property bytes (in hex) (default: 0x00)
-px <x coord> metasprites pivot x coordinate (default: metasprites width / 2)
-py <y coord> metasprites pivot y coordinate (default: metasprites height / 2)
-pw <width> metasprites collision rect width (default: metasprites width)
-ph <height> metasprites collision rect height (default: metasprites height)
-spr8x8 use SPRITES_8x8
-spr8x16 use SPRITES_8x16 (this is the default)
-spr16x16msx use SPRITES_16x16
-b <bank> bank (default 0)
-keep_palette_order use png palette
-noflip disable tile flip
-map Export as map (tileset + bg)
-use_map_attributes Use CGB BG Map attributes
-use_nes_attributes Use NES BG Map attributes
-use_nes_colors Convert RGB color values to NES PPU colors
-use_structs Group the exported info into structs (default: false) (used by ZGB Game Engine)
-bpp bits per pixel: 1, 2, 4 (default: 2)
-max_palettes max number of palettes allowed (default: 8)
(note: max colors = max_palettes x num colors per palette)
-pack_mode gb, sgb, sms, 1bpp (default: gb)
-tile_origin tile index offset for maps (default: 0)
-tiles_only export tile data only
-maps_only export map tilemap only
-metasprites_only export metasprite descriptors only
-source_tileset use source tileset (image with common tiles)
-keep_duplicate_tiles do not remove duplicate tiles (default: not enabled)
-bin export to binary format
-transposed export transposed (column-by-column instead of row-by-row)