Serial e Bluetooth

#include <SoftwareSerial.h>

SoftwareSerial bt(53 , 52); // TX RX
byte caractere;
byte portao = 49; // 1 a


void setup()
{
  Serial.begin(9600);
  bt.begin(9600);
  pinMode(portao, OUTPUT);
}

void loop()
{
  if (bt.available())
  {
    caractere = bt.read();
    if (caractere == 'A')
    {
      digitalWrite(portao, HIGH); // 1 a
      bt.println("OK, port A/F.");
    }
    if (caractere == 'a')
    {
      digitalWrite(portao, LOW);
      bt.println("OK, port a/f.");
    }
  }
      char ler = 0;
    if(Serial.available())
    {
      ler = Serial.read();
      Serial.println(ler);
    }
}