IMHO, any remaining IO pins on your Arduino should ALWAYS be used to drive some sort of indicator lights - even if they just randomly blink/flicker. Try to utilize many different colors too.
Just though I'd share that. 
IMHO, any remaining IO pins on your Arduino should ALWAYS be used to drive some sort of indicator lights - even if they just randomly blink/flicker. Try to utilize many different colors too.
Just though I'd share that.