8. LED Blink

How do you plan to solve it?

Connect you led with your desired pin, to make sure that the current is around 10mA 
 

I        = 10mA

Vled  = 2v

Vdd   = 5v

R       =  ? 

Assume that the voltage drop across the LED is 2v.

R = V/I, -> (5-2)/10mA -> ~300ohm

 R~=300ohm

/*Paste your code here*/
#define LED_PIN 13   // LED pin number 
#define DELAY_ON_TIME 400  // delay time in ms
#define DELAY_OFF_TIME 800 // delay time in ms

void setup()
{
	pinMode(LED_PIN,OUTPUT);
}

void loop()
{
	digitalWrite(LED_PIN,HIGH);
	delay(DELAY_ON_TIME);
	digitalWrite(LED_PIN,LOW);
	delay(DELAY_OFF_TIME);
}

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