3DS-Controller

Sending keystrokes from the 3DS to a computer (or more).

How to use

1. Download and compile the latest source code of 3DS-Controller-PC. *Check the bottom of the readme for more info.

2. Download the latest release of HandController.3dsx.

3. Place and create files and folders so you have the same directory structure on the SD Card of your 3DS.

📂 SD Card
┣ 📂 3ds
┃ ┣ 📜 HandController.3dsx
┃ ┣ 📂 data
┃ ┃ ┣ 📂 HandController
┃ ┃ ┃ ┗ 📜 controller.ini

File	Full Path
HandController.3dsx	SDCard\3ds\HandController.3dsx.
controller.ini	SDCard\3ds\data\HandController\controller.ini

4. Add the IP and PORT that your computer will be listening on to the controller.ini file.

Example contents of controller.ini:

192.168.8.104 8889

Note

Keep in mind that if you use a local IP, your 3DS also has to be on the same network.

On the other hand if you use a public IP, your 3DS has to be on a different network and the port needs to be forwarded correctly.

---

Some path theory

Please note that in reality, the provided .3dsx file can be placed anywhere on the system.

To make it clearer for how it looks for the controller.ini file, here's a table that hopefully explains it:

Started from the homebrew launcher	relative path	Will look for
icon	.3dsx directory	data\HandController\controller.ini
3dslink NetLoader	root directory	3DS\data\HandController\controller.ini

I am reluctant to use absolute paths, since I want to keep the behaviour of using the relative paths in case some users keep their homebrew apps in a different location.

3dslink NetLoader, however, forces me to.

How to edit and compile source code yourself

1. Download Docker Desktop.
2. Pull the provided docker image.
   The image includes a devkitarm development environment and a ready-to-use makefile with partial C++20 support enabled.
3. Start the image as a container and attach VSCode to it. (Or use any other form of containerized development.)

I also advise you to create a volume when launching the container so that you can freely access the container's filesystem for build output files or anything else.

If not, you can use the built-in 3DSLink tool to very conveniently upload the compiled .3dsx to the console.
This is the recommended way to develop 3DS Homebrew.

The syntax is like this: >3dslink {path/to/file} -a {ip-of-3ds}
Example: >3dslink out/HandController.3dsx -a 192.168.8.101

You can find tutorials for all of this online if you need any help.

Want more?

The 3DS application sends 12 bytes of data to a UDP Server everytime a button is pressed.
The data is constructed as follows:

std::array<uint32_t, 3> get_key_states() {
    hidScanInput();
    return { hidKeysDown(), hidKeysHeld(), hidKeysUp() };
}

This means that it can be paired with anything that can recieve and interpret said data.
Like your phone or a smart microwave.

This will be extended in the future to include touch screen and c-stick data.