diff --git a/app/src/main/java/com/example/co2sense_app/BLEDevice.java b/app/src/main/java/com/example/co2sense_app/BLEDevice.java
index 969a4e1..0c0cf36 100644
--- a/app/src/main/java/com/example/co2sense_app/BLEDevice.java
+++ b/app/src/main/java/com/example/co2sense_app/BLEDevice.java
@@ -26,13 +26,9 @@ import androidx.annotation.RequiresApi;
 import androidx.core.app.ActivityCompat;
 import androidx.core.content.ContextCompat;
 
-import java.nio.ByteBuffer;
 import java.util.NoSuchElementException;
 
 public abstract class BLEDevice {
-    private enum ConnectionState {NONE, STARTING_BT, CONNECTING, CONNECTED};
-    private ConnectionState state = ConnectionState.NONE;
-
     private static final int REQUEST_BT_PERMISSION = 16535;
     private static final int REQUEST_ENABLE_BT = 16536;
     private static final int SELECT_DEVICE_REQUEST_CODE = 16537;
@@ -114,7 +110,7 @@ public abstract class BLEDevice {
             @Override
             public void onCharacteristicChanged(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic) {
                 super.onCharacteristicChanged(gatt, characteristic);
-                Log.d("bt", "onCharacteristicChanged: "+ ByteBuffer.wrap(characteristic.getValue()).getShort());
+                mainClass.onCharacteristicChanged(gatt, characteristic);
             }
         });
     }
@@ -165,6 +161,10 @@ public abstract class BLEDevice {
 
     }
 
+    protected void onCharacteristicChanged(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic) {
+
+    }
+
     @RequiresApi(api = Build.VERSION_CODES.S)
     public void startScan(ScanCallback callback){
         scanCallback = callback;
diff --git a/app/src/main/java/com/example/co2sense_app/CO2Sensor.java b/app/src/main/java/com/example/co2sense_app/CO2Sensor.java
index 6925477..509d6fe 100644
--- a/app/src/main/java/com/example/co2sense_app/CO2Sensor.java
+++ b/app/src/main/java/com/example/co2sense_app/CO2Sensor.java
@@ -36,9 +36,17 @@ public class CO2Sensor extends BLEDevice {
     @Override
     protected void onServicesDiscovered() {
         super.onServicesDiscovered();
+        Log.d("CO2Sense", "onServicesDiscovered: ");
         enableNotifications(bluetoothGatt);
     }
 
+    @Override
+    protected void onCharacteristicChanged(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic) {
+        super.onCharacteristicChanged(gatt, characteristic);
+        byte[] rawValue = characteristic.getValue();
+        Log.d("CO2Sense", "onCharacteristicChanged: "+characteristic.getIntValue(BluetoothGattCharacteristic.FORMAT_UINT16, 0));
+    }
+
     @SuppressLint("MissingPermission")
     private void enableNotifications(BluetoothGatt bluetoothGatt) {
         BluetoothGattService ES = bluetoothGatt.getService(ENVIRONMENTAL_SENSING_UUID);