Not exactly schematics, but [Duckman] has some Arduino pinout diagrams he made using ASCII-art. These could be useful when pasted into source code as comments, documenting the pinouts for your ...

Points of Interest : Circuit Canvas simplifies the creation of illustrated wiring diagrams. It is designed to be easy to use and fast, allowing users to create diagrams in less than a minute. The ...

I use that in a lot of Circuit VR posts so you can click on a circuit and see it live. However, the simulator does not save the source code in the virtual Arduino. You have to do that yourself.

Here is the circuit of an Arduino-based Panic Alarm! The wiring is very simple so that even a novice can construct this interesting circuit without any difficulty. Arduino is a family of ...