Please check out 3DSKontrollr+, a rewrite from scratch of this project.
Control your Windows PC with a Nintendo 3DS console.
This Project is based on this one: https://github.com/jwarby/3ds-to-pc-controller But the server is written on C#, has a nice UI and is designed for Windows. Also it has support for the B button.
##THIS IS AN EXPERIMENTAL ABANDONED PROJECT If you want to download binaries for the latest stable version, go to https://d.thebit.link/3dsk
This project is licensed under MIT, so you can do anything you want with the code.