int BOTON = 2;
int LED = 7;
int ESTADO = LOW;

void setup() {
  pinMode (BOTON, INPUT);
  pinMode (LED, OUTPUT);
}
void loop(){
  while(digitalRead(BOTON) == LOW){
  
  }

  ESTADO = digitalRead(LED);
  digitalWrite(LED, !ESTADO);
  while(digitalRead(BOTON) == HIGH){
    
  }
}