#include "BluetoothSerial.h" //V_Инсталлирована
#if !defined(CONFIG_BT_ENABLED) || !defined(CONFIG_BLUEDROID_ENABLED)
#error Bluetooth is not enabled! Please run `make menuconfig` to and enable it
#endif
BluetoothSerial SerialBT;
int received;// received value will be stored in this variable
char receivedChar;// received value will be stored as CHAR in this variable
const char turnON='a',    turnOFF='b';
const int LEDpin = 2;
void setup() {   Serial.begin(115200);    pinMode(LEDpin, OUTPUT); 
  SerialBT.begin("ESP32_SRINIBAS"); //Bluetooth device name
  Serial.println("The device started, now you can pair it with bluetooth!");
  Serial.println("To turn ON send: a");
  Serial.println("To turn OFF send: b");              }
void loop() {
    receivedChar =(char)SerialBT.read();
  if(Serial.available()) SerialBT.write(Serial.read());
  
  if(SerialBT.available()) {
    SerialBT.print("Received:");
    SerialBT.println(receivedChar); Serial.print ("Received:");
      Serial.println(receivedChar); 
    //SerialBT.println(receivedChar);//print on the app    
    //SerialBT.write(receivedChar); //print on serial monitor

    if(receivedChar == turnON)
    {SerialBT.println("LED ON:");   Serial.println("LED ON:");
     digitalWrite(LEDpin, HIGH);     }

    if(receivedChar == turnOFF)
    {SerialBT.println("LED OFF:");  Serial.println("LED OFF:");
      digitalWrite(LEDpin, LOW);     }    
 }    delay(20);
}