BLE_Example_3_Characteristics.ino

/*
    Based on Neil Kolban example for IDF: https://github.com/nkolban/esp32-snippets/blob/master/cpp_utils/tests/BLE%20Tests/SampleServer.cpp
    Ported to Arduino ESP32 by Evandro Copercini
*/

#include <BLEDevice.h>
#include <BLEUtils.h>
#include <BLEServer.h>

// See the following for generating UUIDs:
// https://www.uuidgenerator.net/

#define SERVICE_UUID          "4fafc201-1fb5-459e-8fcc-c5c9c331914b"
#define CHARACTERISTIC1_UUID  "beb5483e-36e1-4688-b7f5-ea07361b26a8"
#define CHARACTERISTIC2_UUID  "688091db-1736-4179-b7ce-e42a724a6a68"
#define CHARACTERISTIC3_UUID  "0515e27d-dd91-4f96-9452-5f43649c1819"

void setup() {
  Serial.begin(115200);
  Serial.println("Starting BLE work!");

  BLEDevice::init("MyESP32");
  BLEServer *pServer = BLEDevice::createServer();
  BLEService *pService = pServer->createService(SERVICE_UUID);
  BLECharacteristic *pCharacteristic1 = pService->createCharacteristic(
                                         CHARACTERISTIC1_UUID,
                                         BLECharacteristic::PROPERTY_READ |
                                         BLECharacteristic::PROPERTY_WRITE
                                       );
  pCharacteristic1->setValue("Hi 1");
  
  BLECharacteristic *pCharacteristic2 = pService->createCharacteristic(
                                       CHARACTERISTIC2_UUID,
                                       BLECharacteristic::PROPERTY_READ |
                                       BLECharacteristic::PROPERTY_WRITE
                                     );
  pCharacteristic2->setValue("Hi 2");

  BLECharacteristic *pCharacteristic3 = pService->createCharacteristic(
                                       CHARACTERISTIC3_UUID,
                                       BLECharacteristic::PROPERTY_READ |
                                       BLECharacteristic::PROPERTY_WRITE
                                     );
  pCharacteristic3->setValue("Hi 3");
  
  pService->start();
  BLEAdvertising *pAdvertising = pServer->getAdvertising();
  pAdvertising->start();
  Serial.println("3 Characteristics defined! Now you can read it in your phone!");
}

void loop() {
  // put your main code here, to run repeatedly:
  delay(2000);
}