How do you plan to solve it?
Assuming the voltage drop of LED is 1.8v
From the ohms law formula R=V/I I will calculate the resistor needed to limit the current flows through the LED.
Vs = voltage from arduino pin 5v
Vf = voltage drop through LED 1.8
I = Required amp 0.01A (10miliamp)
R=Vs-Vf/I -> 5v-1.8v/0.01A -> 3.2v/0.01A -> 320ohm R=320ohm (Standard Res is 330ohm)
/*Paste your code here*/
void setup() {
pinMode(4, OUTPUT);
}
void loop() {
digitalWrite(4, HIGH);
delay(400);
digitalWrite(4, LOW);
delay(800);
}
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