#include <SoftwareSerial.h>

#define RxD 10
#define TxD 11
char Drink = 0;
const int led1 = 13;
SoftwareSerial BTSerial(RxD, TxD);

void setup(){
  // replace BAUDRATE as suggested
  BTSerial.begin(9600);
  Serial.begin(57600);
  BTSerial.print("AT\r\n");

}

void loop(){
 {if (BTSerial.available())
    Serial.write(BTSerial.read());

  if (Serial.available())
    BTSerial.write(Serial.read());}

  if (BTSerial=='1') //wenn das Bluetooth Modul „0“ empfängt...
  {
    digitalWrite(led1,HIGH);

    if (BTSerial=='2') //wenn das Bluetooth Modul „0“ empfängt...
  {  BTSerial.write("HIER");
    digitalWrite(led1,LOW);
}
}}