int primero;
int led = 2;
int boton = 15;
int sel=0;

void setup(){
  Serial.begin(115200);
    pinMode(led, OUTPUT);
  pinMode(boton, INPUT_PULLUP);
}
void loop(){
 if (sel==0){
    primero=random(0,2);
    digitalWrite( led, primero);
    Serial.println(primero);
    delay(1000);
    sel=1;
 }
  
}