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 ...

If the computer isn’t trying to upload any code, it instructs the microcontroller to run the code that’s already stored inside. Original Circuit Diagram: Arduino UNO R3. Now, have a look at our ...

Sometimes, you'll also encounter Arduino tutorials in the wild that include links to a Wokwi circuit as creators and developers typically create one to show the project's schematic diagram. Other ...

The resistor values (R1&R2) in the circuit diagram provide some over-voltage protection then measuring low voltages. Keep it in mind that any input voltage higher than about 55V could fry the Arduino.

That means if you have everything working, save your circuit, and close your browser you’ll have to recreate your Arduino code next time. Luckily, I tested this out before I lost any work.