Custom Build Question??

Hello to the community, my question as follows. I want to build a project with a C# ready Micro controller board similar to arduino, called NetDuino. I want to take advantage of unity's physics computation capabilities as another features, i want to make also a mobile application, all of this to work together to control my project. I cant just use a serial communication to send the data to the board, i need the board itself to compute, so i need a way to build the project to the board. I know unity build to certain platforms, but I guess I need like a special build for this. Can someone give me some hints to achieve this? An unity program running on a micro controller board. Thank you.