GBDK - Revision history

Bbbbbr: Add more of the original GBDK authors

2022-12-07T07:44:02Z

Add more of the original GBDK authors

PinoBatch: /* References */ This wiki appears not to have Cite.php

2022-01-16T16:49:10Z

‎References: This wiki appears not to have Cite.php

Bbbbbr: Add GBDK-2020

2021-06-24T05:25:36Z

Add GBDK-2020

Caseyweederman: Adding link to library reference, adding to category

2016-06-03T14:32:21Z

Adding link to library reference, adding to category

Npzman: /* Distribution */

2015-05-07T13:46:13Z

‎Distribution

Davisr: Adjusted information about OS X version to be more specific with its current status.

2009-06-28T04:25:22Z

Adjusted information about OS X version to be more specific with its current status.

Davisr: Added SourceForge download page link

2009-06-26T21:47:37Z

Added SourceForge download page link

Davisr: First revision of the page

2009-06-26T21:35:11Z

First revision of the page

New page

The Game Boy Development Kit (often referred to as the GBDK) is a compilation of tools, created by David Galloway, Michael Hope, Sandeep Dutta, and Daniel Rammelt that holds the intention of allowing users to program for the Nintendo Game Boy platform in either C or GB-Z80 Assembly. Currently, the project is not being developed. Although no official announcement was made, development for the GBDK ceased in 2002, after GBDK-v2.96a was released, due to Hope's "life getting in the way."<ref>[http://gbdk.sourceforge.net/ GBDK Homepage]</ref>

== Distribution ==
The GBDK is available on it's SourceForge page in both source code and binary formats for the x86 platform. The GBDK is readily available for the following architectures:
* Source code for compiling on
** Linux for Linux
** Linux for Win32 (using mingw32)
** Cygwin for Win32
* Binaries for
** Windows/DOS
** Linux
There is no official version for Mac OS X, however, a working private alpha has been created by davisr.

== Compiler, assembler, linker and libs: GBDK ==
The information in this section is taken from [http://gbdk.sourceforge.net/tools.html the GBDK SourceForge page].

=== The Compiler ===
The GBDK's lcc compiler is based on [http://www.cs.princeton.edu/software/lcc/ lcc], a retargetable compiler for ANSI C. The compiler turns C source code into code for the GB-Z80. The compiler defines the following sizes for basic types:
{| class="wikitable" border="1"
|-
! Type
! Size (in bytes)
! Min
! Max
|-
| char
| 1
| -128
| 127
|-
| unsigned char
| 1
| 0
| 255
|-
| int
| 1
| -128
| 127
|-
| unsigned int
| 1
| 0
| 255
|-
| long
| 2
| -32768
| 32768
|-
| unsigned long
| 2
| 0
| 65535
|-
| long long
| 4
| -2147483648
| 2147483647
|-
| unsigned long long
| 4
| 0
| 4294967296
|-
| float
| 4
| N/A
| N/A
|-
| double
| 4
| N/A
| N/A
|-
| pointer
| 2
| N/A
| N/A
|}
Since the CPU is an 8-bit processor, working with int values is much more efficient than working with long values. However, overflows still need to be handled carefully.

When generating a Game Boy image, the linker will look for undefined symbols in each of the object files listed in the ''lib/gb.lib'' text file. If one of these object files contains the symbol, it will be linked with the main program. If none of these object files contain the symbol, the linker will generate an error. Therefore, there is no need to explicitly link the main program with the standard libraries.

==== Examples of lcc usage ====
* Compile a C source file (source.c) and generate a Game Boy image (image.gb):
lcc -o image.gb source.c
* Assemble an assembly source file (source.s) and generate a Game Boy image (image.gb):
lcc -o image.gb source.s
* Compile a C source file (source.c) and generate an object file (object.o):
lcc -c -o object.o source.c
* Assemble an assembly source file (source.s) and generate an object file (object.o):
lcc -c -o object.o source.s
* Link two object files (object1.o and object2.o) and generate a Game Boy image (image.gb):
lcc -o image.gb object1.o object2.o
* Generate a Game Boy image (image.gb) from an assembly source file (source.s), a C source file (source.c), and an object file (object.o):
lcc -o image.gb source.s source.c object.o
The following flags allow to pass options to the preprocessor, the compiler, the assembler, and the linker:
-Wp
-Wf
-Wa
-Wl
A typical usage of these flags is for generating listing and map files:
* A listing file is produced by the assembler if you use the ''-Wa-l'' flag. The name of this file is the same as the object file, with the .lst extension. It contains the assembly code and source. If the assembler generates error messages, listing files are necessary for locating these errors.
* A map file is produced by the linker if you use the ''-Wl-m'' flag. The name of this file is the same as the image file, with the .map extension. It contains informations about where functions and variables are located in ROM. If the linker generates error messages, map files are useful for locating these errors.
* A symbol file for the [[no$gmb]] emulator is produced by the linker if you use the ''-Wl-j'' flag. The name of this file is the same as the image file, with the .sym extension. It contains informations that can be used by the no$gmb built-in debugger.
It is generally a good habit to generate listing and map files.

=== The Assembler ===
The assembler is based on [http://shop-pdp.kent.edu/ashtml/asxxxx.htm ASxxxx Cross Assemblers].

The Game Boy processor is very similar to the Z80, although some of the instructions are missing, more were added by Nintendo. Also, the second set of registers (BC', DE', HL', AF') and the index registers (IX, IY) are missing and, consequently, there are no DD and FD opcode tables. Finally, I/O ports are gone and so are all IN/OUT opcodes. for a descriptions of the changed instructions, read the [[Game Boy FAQ]][http://fms.komkon.org/GameBoy/ (link)].

The names of some Game Boy specific opcodes have been modified, as seen below.
LD (HLI),A > LD (HL+),A
LD (HLD),A > LD (HL-),A
LD A,(HLI) > LD A,(HL+)
LD A,(HLD) > LD A,(HL-)
ADD SP,OFFSET > LDA SP,OFFSET(SP)
LDHL SP,OFFSET > LDA HL,OFFSET(SP)
The ''LDA'' opcode means "load address", like in 68x00 assembly. These instructions are called like this because both are orthogonal (they do the same thing on two different registers).

The assembler accepts the following flags:

ASxxxx Assembler V01.75 (GameBoy Z80-like CPU)

Usage: [-dqxgalopsf] outfile file1 [file2 file3 ...]
d decimal listing
q octal listing
x hex listing (default)
g undefined symbols made global
l create list outut outfile[LST]
o create object output outfile[o]
s create symbol output outfile[SYM]
p disable listing pagination
f flag relocatable references by ' in listing file
ff flag relocatable references by mode in listing file

=== The Linker ===
The linker is based on [http://shop-pdp.kent.edu/ashtml/asxxxx.htm ASxxxx Cross Assemblers]. It has been extended in particular to support generation of Game Boy images.

The linker accepts the following flags:
ASxxxx Linker V01.75

Startup:
-- [Commands] Non-interactive command line input
-c Command line input
-f file[LNK] File input
-p Prompt and echo of file[LNK] to stdout (default)
-n No echo of file[LNK] to stdout
Usage: [-Options] outfile file [file ...]
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
-yo Number of rom banks (default: 2)
-ya Number of ram banks (default: 0)
-yt MBC type (default: no MBC)
-yn Name of program (default: name of output file)
-yp# Patch one byte in the output GB file (# is: addr=byte)
Map format:
-m Map output generated as file[MAP]
-j no$gmb symbol file generated as file[SYM]
-x Hexadecimal (default)
-d Decimal
-q Octal
Output:
-i Intel Hex as file[IHX]
-s Motorola S19 as file[S19]
-z Game Boy image as file[GB]
List:
-u Update listing file(s) with link data as file(s)[.RST]
End:
-e or null line terminates input

=== The include files and libraries ===
Several include files are part of the GBDK. Some of them only define useful macros (with no code associated), while others define functions implemented in separate object modules. The libraries are split in several small object files in order to reduce the size of the final image file (only the required modules are linked with the main program). The include files and libraries are divided in the following groups.

==== Runtime support ====
The ''crt0.o'' object module contains the basic C runtime library, with Game Boy initialization routines, C support, and other essential things. This library is required and automatically linked with every program.

The ''gb/gb.h'' include file defines basic Game Boy related macros and functions. It also includes the ''hardware.h'' file that defines Game Boy hardware registers.

==== Standard C libraries ====
The ''ctype.h'', ''stdarg.h'', ''stdlib.h'', and ''types.h'' include files define some functions found in the standard C libraries.

==== Console I/O ====
Basic console I/O is provided through a set of functions defined in the ''console.h'' and ''stdio.h'' include files. note that console I/O uses most of the tiles and sprites of the Game Boy, and thus is not easily mixable with graphics programs.

==== Simple graphic library ====
Simple graphic functions for drawing points and images on the screen are defined in the ''drawing.h'' include file. Note that the graphic library uses most of the tiles and sprites of the Game Boy.

==== Misc libraries ====
The ''rand.h'' include file defines functions for using the GBDK random generator.

== References ==
<references/>

← Older revision		Revision as of 07:44, 7 December 2022
Line 7:		Line 7:

	'''Original GBDK (through 2.x)''':		'''Original GBDK (through 2.x)''':
−	The original GBDK was created by David Galloway, Michael Hope, Sandeep Dutta, and Daniel Rammelt. It ceased to be updated in 2002 after GBDK-v2.96a was released. The website for the original version is: [http://gbdk.sourceforge.net/ GBDK Homepage]	+	The original GBDK was created by Pascal Felber, Lars Malmborg, John Fuge, David Galloway, Michael Hope, Sandeep Dutta, and Daniel Rammelt. It ceased to be updated in 2002 after GBDK-v2.96a was released. The website for the original version is: [http://gbdk.sourceforge.net/ GBDK Homepage]

@@ Line 224: / Line 224: @@
 The ''rand.h'' include file defines functions for using the GBDK random generator.
-== References ==
+== See also ==
-<references/>
+*[[SDCC output samples]]
 [[Category:GBDK]]

@@ Line 1: / Line 1: @@
-The Game Boy Development Kit (often referred to as the GBDK) is a compilation of tools, created by David Galloway, Michael Hope, Sandeep Dutta, and Daniel Rammelt that holds the intention of allowing users to program for the Nintendo Game Boy platform in either C or GB-Z80 Assembly.  Currently, the project is not being developed.  Although no official announcement was made, development for the GBDK ceased in 2002, after GBDK-v2.96a was released, due to Hope's "life getting in the way."<ref>[http://gbdk.sourceforge.net/ GBDK Homepage]</ref>
+The Game Boy Development Kit (often referred to as GBDK) is a suite of tools that allows users to program for the Nintendo Game Boy platform in C and GB-Z80 Assembly.
 == Distribution ==
-The GBDK is available on it's [http://sourceforge.net/projects/gbdk SourceForge download page] in both source code and binary formats for the x86 platform.  The GBDK is readily available for the following architectures:
+'''GBDK-2020 (3.x and later)''':
-* Source code for compiling on
+GBDK-2020 releases are available at the project's [https://github.com/gbdk-2020/gbdk-2020 Github page] in source and binary formats.
-** Linux for Linux
+* Source and binary releases are available for:
-** Linux for Win32 (using mingw32)
-** Cygwin for Win32
-* Binaries for
-** Windows/DOS
 ** Linux
-There is no official version for Mac OS X, however, a semi-working private alpha has been created by davisr.
+** Windows
-Direct link [http://downloads.sourceforge.net/project/gbdk/gbdk-win32/2.94/gbdk-2.94-win32.exe?r=http%3A%2F%2Fsourceforge.net%2Fprojects%2Fgbdk%2Ffiles%2F&ts=1431005688&use_mirror=internode
+** macOS
-−
 == Compiler, assembler, linker and libs: GBDK ==

@@ Line 179: / Line 179: @@
 === The include files and libraries ===
-Several include files are part of the GBDK.  Some of them only define useful macros (with no code associated), while others define functions implemented in separate object modules.  The libraries are split in several small object files in order to reduce the size of the final image file (only the required modules are linked with the main program).  The include files and libraries are divided in the following groups.
+[[GBDK_libraries|Several include files]] are part of the GBDK.  Some of them only define useful macros (with no code associated), while others define functions implemented in separate object modules.  The libraries are split in several small object files in order to reduce the size of the final image file (only the required modules are linked with the main program).  The include files and libraries are divided in the following groups.
 ==== Runtime support ====
 The ''crt0.o'' object module contains the basic C runtime library, with Game Boy initialization routines, C support, and other essential things.  This library is required and automatically linked with every program.
-The ''gb/gb.h'' include file defines basic Game Boy related macros and functions.  It also includes the ''hardware.h'' file that defines Game Boy hardware registers.
+The ''[[Gb.h|gb/gb.h]]'' include file defines basic Game Boy related macros and functions.  It also includes the ''hardware.h'' file that defines Game Boy hardware registers.
 ==== Standard C libraries ====
@@ Line 200: / Line 200: @@
 == References ==
 <references/>