[Kotlin] Nano33 IoT 기기와 데이터 통신하기

[MainActivity]

import android.bluetooth.BluetoothAdapter
import android.bluetooth.BluetoothDevice
import android.bluetooth.BluetoothSocket
import java.io.IOException
import java.util.*

val deviceAddress = "00:00:00:00:00:00" // Replace with the address of your nano33iot device
val uuid = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB") // UUID for serial communication
var bluetoothSocket: BluetoothSocket? = null

val bluetoothAdapter: BluetoothAdapter? = BluetoothAdapter.getDefaultAdapter()

// Check if device supports Bluetooth
if (bluetoothAdapter == null) {
    // Device does not support Bluetooth
} else {
    // Device supports Bluetooth
    
    // Check if Bluetooth is enabled on device
    if (!bluetoothAdapter.isEnabled) {
        // Request to enable Bluetooth
        val enableBtIntent = Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE)
        startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT)
    }
    
    // Get the Bluetooth device by its address
    val device: BluetoothDevice = bluetoothAdapter.getRemoteDevice(deviceAddress)
    
    // Connect to the device using a Bluetooth socket
    try {
        bluetoothSocket = device.createInsecureRfcommSocketToServiceRecord(uuid)
        bluetoothSocket.connect()
    } catch (e: IOException) {
        // Connection failed
    }
    
    // Send a message to the device
    val outputStream = bluetoothSocket.outputStream
    val message = "Hello from Android phone"
    val bytes = message.toByteArray()
    outputStream.write(bytes)
    
    // Receive a message from the device
    val inputStream = bluetoothSocket.inputStream
    val buffer = ByteArray(1024)
    val numBytes = inputStream.read(buffer)
    val receivedMessage = String(buffer, 0, numBytes)
}

// Close the Bluetooth socket when finished
try {
    bluetoothSocket?.close()
} catch (e: IOException) {
    // Error occurred while closing the socket
}

[Nano33 IoT] by Arduino-IDE

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

#define SERVICE_UUID "4fafc201-1fb5-459e-8fcc-c5c9c331914b"
#define CHARACTERISTIC_UUID "beb5483e-36e1-4688-b7f5-ea07361b26a8"

BLECharacteristic *pCharacteristic;
bool deviceConnected = false;
bool oldDeviceConnected = false;
String receivedMessage = "";

class MyServerCallbacks: public BLEServerCallbacks {
    void onConnect(BLEServer* pServer) {
      deviceConnected = true;
    }

    void onDisconnect(BLEServer* pServer) {
      deviceConnected = false;
    }
};

void setup() {
  Serial.begin(9600);

  BLEDevice::init("nano33iot");
  BLEServer *pServer = BLEDevice::createServer();
  pServer->setCallbacks(new MyServerCallbacks());
  BLEService *pService = pServer->createService(SERVICE_UUID);
  pCharacteristic = pService->createCharacteristic(CHARACTERISTIC_UUID, BLECharacteristic::PROPERTY_READ | BLECharacteristic::PROPERTY_WRITE);
  pCharacteristic->setValue("Hello from nano33iot");
  pService->start();

  BLEAdvertising *pAdvertising = BLEDevice::getAdvertising();
  pAdvertising->addServiceUUID(SERVICE_UUID);
  pAdvertising->setScanResponse(false);
  pAdvertising->setMinPreferred(0x0