#include <Servo.h> ///library

Servo fan; // your name 

void setup() {
  Serial.begin(9600);
  fan.attach(11); //pin it should a  ~ pwm pin
  
}

int pos = 0; //5 , 10 ,  , 

void loop() {
  fan.write(pos); //move to angle 
  delay(100); //wait for 100 miliseconds
  pos +=  10; //increase by 5
  Serial.println(pos);
  if(pos > 180){
    pos = 0;
  }
}


//0 - 180