byte flag=0;
int ledState = 0;
int interval = 1000;
int previousMillis = 0;

int rele = 10;
int rele_gnd = 11;
int led = 14;
int pulsador = 15;
int gnd = 16;
int mode = 17;
int clock_pin = 8;
int clock_gnd = 9;


byte val =0x00;


void setup() {
  Serial.begin(19200); 
  pinMode(rele, OUTPUT); 
  pinMode(rele_gnd, OUTPUT);
  pinMode(pulsador, INPUT); 
  pinMode(led, OUTPUT);
  pinMode(mode, INPUT);
  pinMode(gnd, OUTPUT);
  pinMode(clock_pin, OUTPUT);
  pinMode(clock_gnd, OUTPUT);

  digitalWrite(rele, LOW);
  digitalWrite(rele_gnd, LOW);
  digitalWrite(pulsador, HIGH);
  digitalWrite(led, HIGH);
  digitalWrite(mode, HIGH);
  digitalWrite(gnd, LOW);
  digitalWrite(clock_gnd, LOW);
  digitalWrite(clock_pin, HIGH);
  delay(100);
  digitalWrite(clock_pin, LOW);
}

void loop() { 
  if (!digitalRead(pulsador))
  {
    Serial.print(0, BYTE); // activado
  }
  else if (digitalRead(pulsador))
  {
    Serial.print(1, BYTE); // desactivado
  }
  if (!digitalRead(mode))
  {
    Serial.print(2, BYTE); // modo automatico
    if (millis() - previousMillis > interval) {
      previousMillis = millis();   
      if (ledState == LOW)
        ledState = HIGH;
      else
        ledState = LOW;

      digitalWrite(led, ledState);
    }
  }
  else if (digitalRead(mode))
  {
    Serial.print(3, BYTE); // modo manual
  }

  delay(100);

  if(Serial.available() > 0)
  {
    val = Serial.read();
    if (val==0x10) digitalWrite(rele,HIGH);
    else if (val==0x20)  digitalWrite(rele, LOW);  
    else if (val==0x30) 
    {
      digitalWrite(clock_pin, HIGH);
      delay(100);
      digitalWrite(clock_pin, LOW);
    }
  }
}