/*
 Controlling a servo position using a potentiometer (variable resistor)
 by Michal Rinott <http://people.interaction-ivrea.it/m.rinott>

 modified on 8 Nov 2013
 by Scott Fitzgerald
 http://www.arduino.cc/en/Tutorial/Knob
*/

#include <Servo.h>

Servo motor;  // create servo object to control a servo


int val;    // variable to read the value from the analog pin
int botao = 7; //entrada do botão
int velocidade = 20;

void setup() {
  motor.attach(9);  // attaches the servo on pin 9 to the servo object
  pinMode(botao, INPUT_PULLUP);
}

void loop() {          // reads the value of the potentiometer (value between 0 and 1023)
  val = map(analogRead(A0), 0, 1023, 0, 180);     // scale it to use it with the servo (value between 0 and 180)
  motor.write(val);                  // sets the servo position according to the scaled value
  delay(velocidade); 
  if(digitalRead(botao)==LOW){
      for (int k=val; k>=0; k--){
      motor.write(k);
      delay(velocidade);
    }
    for (int k=0; k>=180; k++){
      motor.write(k);
      delay(velocidade);
    }
     for (int k=180; k>=val; k--){
      motor.write(k);
      delay(velocidade);
    }
  }                       // waits for the servo to get there
}