LED fading example project


I'm totally new in working with the arduino and electro overall. I was building the example fade project (http://arduino.cc/en/Tutorial/Fade) when I was wondering what the line to 5v does? It seems like there is an unnecessary loop from the 5v to the ground, seems to me you already get power from your digital in?

But then again, I'm a big noob in this, so it could also be i'm dead wrong. I also found this example (http://arduino.cc/en/Tutorial/Fading) which I think is more logical.

Both ways work perfectly btw, just wondering. :slight_smile:


You're right. The +5V connection from the uno to the breadboard in that first example serves no purpose at all. But only such a very very simple project like that would not need it.

But the +5V line does not loop to ground. That would cause a short and possibly damage the uno. And its a digital output that is providing the power. A digital input would not light the led.


Thnx Paul! I see it now, it's a kind of habit to always connect the +5V and ground to the breadboard i guess, just in case you need it (which is probably always in bigger projects)

Also see now it doesn't form a loop as I thought at first and indeed a digital output; still learning, thanks again!