Gameboy development environment

I do a lot of weird code stuff. Recently, I was writing a ROM for a Gameboy hardware-platform.

Here is how I set it up my dev environment on Mac OS 10.8.2.

A lot of "old-timers" I talked to would have serious issues with my advice, but this made my preferred language work on my preferred OS using good tools, with as little fuss as possible. I am an older-timer, and I think it's good advice, as a general problem-solving approach.

I shouldn't have to use ASM, in Windows 98 to get things working the way I want. This is 2013, for God's sake. Let's try something better.

First install Xcode, so you can compile stuff. Install the command-line tools (fuzzy on this, did it a long time ago.)

Basically make and gcc should be in your path.

  • GBDK: I downloaded a pre-compiled version, and extracted to /opt/gbdk
  • RGBDS: I used rgdbs-linux, and just ran make, seemed to work great. copied the whole folder into opt, so it was with the gbdk.
  • Emulator: I used visualboy advance. It doesn't have a debugger, but seems to run games ok. it associates with .gb and .gbc ROM files.
  • DOS tools: I got the wave tool and Advanced PCX2GB from dos-tools extract them to /opt/dos
  • Windows Tools: I installed Wine Bottler and got no$gmb (32bit version, without sound) and all the windows tools from Windows Tools to run, in a single prefix. This adds color image map/tile support, font support and more. no$gmb has a debugger, which is pretty rad, but I couldn't get the sound working. I bottled all the apps, so they have nice icons, and installed them all to one winebottler prefix, to save space.

Now, install DOSBox and add a mount command & tools to path in your autoexec. Do this by editing the bottom of ~/Library/Preferences/DOSBox 0.73 Preferences to look like this:

@echo off
mount H /Users/konsumer
mount D /opt/dos
set PATH=D:\;%PATH%

Replace "konsumer" with your username. Now you have access to your home dir (H:) & dostools (in path, D:)

I keep my projects in ~/Documents/Projects. Here is how I make an image:

use gimp to make a PCX image 160x144 named in Documents/Projects/coolgame/logo.pcx fire up dosbox

type these:

cd Documents/Projects/coolgame
pcx2gb o d logo.pcx logo_tile.c logo_map.c

Looking at DOSBox Usage I think you could add stuff that works from command-line, directly, but I didn't bother (it's not super-common that I need to make images or whatever.)

Then, I made a directory with a Makefile that looks like this:

GBDK = /opt/gbdk
CC   = ${GBDK}/bin/lcc -Wa-l -Wl-m -Wl-j
RGB = /opt/rgbds/rgbfix

BINS   =

all:   $(BINS)

%.o:   %.c
   $(CC) -c -o $@ $<

%.s:   %.c
   $(CC) -S -o $@ $<

%.o:   %.s
   $(CC) -c -o $@ $<   %.o
   $(CC) -o $@ $<

%.gbc:   %.o
   $(CC) -o $@ $< && ${RGB} -vcs -l 0x33 -p 0 $@

   rm -f *.o *.lst *.map *.gb *.gbc *~ *.rel *.cdb *.ihx *.lnk *.sym *.asm

Make a file called mygame.c, that looks like this:

#include <gb/gb.h>
#include <stdio.h>

#include "logo_tile.c"
#include "logo_map.c"

void main() {
    // load logo
    set_bkg_data(0,255, tiledata);
    VBK_REG = 1;
    VBK_REG = 0;
    set_bkg_tiles(0,0,20,18, tilemap);


    printf(" \n\n\n\n\n\n\n\nYour game goes here.\n");

Now, you can run make, and it will compile mygame.c to This is a basic boilerplate, you can do lots of other stuff, read docs on rgbfix for setting ROM title, etc.

As a sidenote, I used Sublime Text, a great code-editor. You should get something that syntax-highlights.

It's also handy if you have a bunch of c files, you can run:

make, and it will compile testsound.c to

type open to run it.

You just made yer first gameboy game. Yer an "old-timer".