Export sketch from ArdunityApp
To connect Unity Scene with Arduino Board, you should upload Arduino Sketch with Unity Scene information to the board.
Ardunity makes you not to do extra coding utilizing Arduino IDE, as it is creating the Sketch automatically.
The Sketch Export function is performed by ArdunityApp included in the Unity Scene.
Therefore, if you need the Sketch to upload to a board, you need to find a ArdunityApp in Unity Scene.
The best way to find is to open Ardunity Wire Editor and click the ArdunityApp.
So you can run the Export Sketch menu through Inspector View of the Unity Editor in the ArdunityApp you find.
If you specify the file location, Arduino Sketch is generated and saved automatically.
Arduino Sketch saved can be uploaded to the board by opening with Arduino IDE.