Setting up Development Environment

Setup

• Install devkitARM. If it's already installed, update it. On Windows there's a GUI installer. On Linux/Mac there's a perl-script. Make sure you also select ctrulib when installing.
• Download the files in the ctrulib repository (even though the library has already been installed) because the repository contains a 3DS project template and examples.
• Depending on the kind of homebrew you want to develop, you may be interested in installing and using additional libraries and tools which don't ship alongside devkitARM/libctru. A list of them can be found in Homebrew Libraries and Tools.

Linux

• First get the devkitARM updater Perl script for Linux.
• Run it with superuser privileges if your /opt directory is not marked world read-writeable.
• Get ctrulib from Smealum's GitHub repository, build and install it.

sudo apt-get install git curl
curl -L http://sourceforge.net/projects/devkitpro/files/Automated%20Installer/devkitARMupdate.pl/download -o devkitARMupdate.pl
chmod +x ./devkitARMupdate.pl
sudo -s
./devkitARMupdate.pl /opt/devkitpro
cd /opt/devkitpro
git clone https://github.com/smealum/ctrulib.git
cd ctrulib/libctru
export DEVKITPRO=/opt/devkitpro
export DEVKITARM=$DEVKITPRO/devkitARM
make
make install
exit
echo "export DEVKITPRO=/opt/devkitpro" >> ~/.bashrc
echo "export DEVKITARM=$DEVKITPRO/devkitARM" >> ~/.bashrc
echo "export PATH=$PATH:$DEVKITARM/bin" >> ~/.bashrc
source ~/.bashrc

Building the examples

3DS examples are still being created. Currently there are a few examples in the separate ctrulib download under the "examples" folder.

• arm11u: simple homebrew example
• sdmc: demonstrates how to access files on the SD card
• mic: demonstrates how to read sound from the microphone
• gpu: demonstrates how to render 3D geometry with the GPU

Building the examples on Linux with Netbeans

• Go to File->New Project...
• Select C/C++ Project with existing code
• Navigate to the examples directory and select the folder for the project you want to build; eg. /home/vtsingaras/3ds/examples/app_launch
• Leave Configuration Mode to 'Automatic' and click 'Finish'.
• It will fail to build. Now edit Makefile and insert these two lines, adjusting for your devkitpro path, at the top:

export DEVKITPRO=/opt/devkitpro
export DEVKITARM=/opt/devkitpro/devkitARM

• Right-click the project and go to Properties->Code Assistance and click C Compiler.
• In include directories enter

/opt/devkitpro/devkitARM/include;/opt/devkitpro/ctrulib/libctru/include

adjusting again for your devkitPro path.

• Do the same for 'C++ Compiler'.
• Go to 'Run' and click 'Clean and Build Project'.
• Now right-click on the project and select Code Assistance->Reparse Project.

Now you can use Netbeans' code completion feature and build your project from the Run menu.

Building homebrew for distribution

To build your homebrew open a terminal, browse to your homebrew's folder and run make.

• This will build a .elf file and a .3dsx file together with an icon. The icon and .3dsx file are the format required for the Homebrew Channel.

• To build a Gateway-compatible .3ds file you need to strip the .elf file and use makerom on it (with the provided RSF file):

arm-none-eabi-strip [ELF file]
makerom -f cci -o [.3ds file] -rsf [RSF file] -target d -exefslogo -elf [ELF file] -icon [icon file] -banner [banner file]