#include <Keypad.h> 
#include <Servo.h>
 
#define servo_delta_var 10
#define base_minimo 0
#define base_maximo 180
const byte ROWS = 4;  // four rows  
const byte COLS = 4;   // four columns 
// define os valores para cada botao do teclado
char hexaKeys[ROWS][COLS]={ {'1','2','3','A'}, 
{'4','5','6','B'}, 
{'7','8','9','C'}, 
{'*','0','#','D'} }; 
// connect to the column pinouts of the keypad 
byte colPins[COLS] = {5, 4, 3, 2}; // Pins connected to C1, C2, C3, C4
// connect to the row pinouts of the keypad
byte rowPins[ROWS] = {13, 12, 8 ,7}; // Pins connected to R1, R2, R3, R4
// initialize an instance of class NewKeypad
Keypad customKeypad = Keypad( makeKeymap (hexaKeys), rowPins, colPins, ROWS, COLS); 

signed int atraso;
Servo servo_base;
int servo_base_pin=10;
signed int angulo_base;

void setup(){ 
  Serial.begin(9600); 
  servo_base.attach(servo_base_pin);
  angulo_base = 90;  
  atraso = 50;
}

void loop(){ 
  char valorChave = customKeypad.getKey(); 
  switch (valorChave){
  case '4' : if (angulo_base<base_maximo) { 
           angulo_base += servo_delta_var; 
           Serial.print(valorChave);
           Serial.print(" : ");
           Serial.println(angulo_base);
        }
       break;
   case '6' : if (angulo_base>base_minimo) { 
          angulo_base -= servo_delta_var; 
          Serial.print(valorChave);
          Serial.print(" : ");
          Serial.println(angulo_base);
        }
        break;
    }
    servo_base.write(angulo_base);
    delay(atraso);
}