/*
Using analogWrite to control a motor speed. 
Uses pwm to create an effective varying voltage.
*/

/* 3 and 5 are PWM capable on most arduino boards */

int motorFwdPin = 3;
int motorRevPin = 5;

void setup() {
  pinMode(motorFwdPin, OUTPUT);
  pinMode(motorRevPin, OUTPUT);
}

void loop() {
  //speed up
  for (int i = 0; i < 255; i+=64) {
    analogWrite(motorFwdPin, i);
    delay(1000);
  }
  // last one since we never reach full speed
  analogWrite(motorFwdPin, 255);
  
  delay (5000);
  
  //slow down
  for (int i = 255; i > 0; i-=64) {
    analogWrite(motorFwdPin, i);
    delay(1000);
  }
  // set to 0 for stop
  analogWrite(motorFwdPin, 0);
  
}