It is not clear to me whether Pin 13, corresponding to the LED, should be driven by an external voltage or not.
From the documentation,
LED: 13. There is a built-in LED driven by digital pin 13. When the pin is HIGH value, the LED is on, when the pin is LOW, it's off.
However, in the "Blink" example code I am running, the Pin 13 appears to be driven by the ATmega328:
void setup() {
// initialize digital pin 13 as an output.
pinMode(13, OUTPUT);
}
// the loop function runs over and over again forever
void loop() {
digitalWrite(13, HIGH); // turn the LED on (HIGH is the voltage level)
delay(100); // wait for a second
digitalWrite(13, LOW); // turn the LED off by making the voltage LOW
delay(2000); // wait for a second
}
If I now attach a voltage source to Pin 13, will there be contention issues?
