使用小米手环和 BLE 测量心率

Question

我正在尝试实现简单的 sdk 以与健身追踪器小米手环配合使用。目前我可以跟踪步数、启动振动、处理传感器触摸，但我在心率测量方面遇到问题。我的 sdk 基于 https://github.com/pangliang/miband-sdk-android。为了测量心率，我需要将描述符写入适当的特性，以便在该特性的值更改时启用处理回调，然后将适当的数据写入心率控制点特性以直接启动心率测量过程。问题是启动这个过程的数据成功写入特征后心率测量过程没有启动（当Mi Band开始测量心率时底部传感器闪烁绿色）。这可能是由于健身手环的新固件（固件版本：4.15.12.10；心率版本：1.3.74.64）或者我的代码存在一些缺陷：

/-------- MiBandProfile --------/
public static final UUID UUID_SERVICE_HEARTRATE = UUID.fromString("0000180d-0000-1000-8000-00805f9b34fb");
public static final UUID UUID_NOTIFICATION_HEARTRATE = UUID.fromString("00002a37-0000-1000-8000-00805f9b34fb");
public static final UUID UUID_CHAR_HEARTRATE = UUID.fromString("00002a39-0000-1000-8000-00805f9b34fb");
public static final UUID UUID_DESCRIPTOR_UPDATE_NOTIFICATION = UUID.fromString("00002902-0000-1000-8000-00805f9b34fb");

/-------- MiBandProtocol --------/
public static final byte[] START_HEART_RATE_SCAN = {21, 1, 1};

/-------- BleProvider --------/
public class BleProvider extends BluetoothGattCallback {

public interface NotifyListener {
     void onNotify(byte[] data);
}

private HashMap<UUID, NotifyListener> mNotifyListeners = new HashMap<UUID, NotifyListener>();
.
.
.
public void setNotifyListener(UUID serviceUUID, UUID charaUUID, NotifyListener listener) {
        //enable chara notofication
        if (this.mGatt == null || !this.mIsServicesDiscovered) {
            if (DBG) Log.d(Debug.TAG, "Device is not connected or services are not discovered");
            return;
        }

        BluetoothGattCharacteristic chara = this.mGatt.getService(serviceUUID).getCharacteristic(charaUUID);

        if (DBG) Log.d(Debug.TAG, "setCharacteristicNotification: " + this.mGatt.setCharacteristicNotification(chara, true));
        BluetoothGattDescriptor descriptor = chara.getDescriptor(MiBandProfile.UUID_DESCRIPTOR_UPDATE_NOTIFICATION);
        if (DBG) Log.d(Debug.TAG, "setValue: " + descriptor.setValue(BluetoothGattDescriptor.ENABLE_NOTIFICATION_VALUE));
        if (DBG) Log.d(Debug.TAG, "writeDescriptor: " + this.mGatt.writeDescriptor(descriptor));
        this.mNotifyListeners.put(charaUUID, listener);
}

@Override
public void onCharacteristicChanged(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic) {
        //this method must be called when the characteristic value was changed but nothing happened :(
        super.onCharacteristicChanged(gatt, characteristic);

        if (this.mNotifyListeners.containsKey(characteristic.getUuid())) {
            this.mNotifyListeners.get(characteristic.getUuid()).onNotify(characteristic.getValue());
        }
}
} //end BleProvider

.
.
.

setNotifyListener(MiBandProfile.UUID_SERVICE_HEARTRATE, MiBandProfile.UUID_NOTIFICATION_HEARTRATE, new BleProvider.NotifyListener(){...});
//waiting few seconds
writeCharacteristic(MiBandProfile.UUID_SERVICE_HEARTRATE, MiBandProfile.UUID_CHAR_HEARTRATE, MiBandProtocol.START_HEART_RATE_SCAN);

也许该协议已被弃用，有人可以与我分享一个新协议。我会很高兴）谢谢。

Answer 1

我正在使用 BLE A&D，以获取我使用的信息：

To find UUID

  @SuppressLint("NewApi")
private void displayGattServicesService(List<BluetoothGattService> gattServices) {
    //  salida.append("Buscando servicio");
    if (gattServices == null)
        return;
    for (BluetoothGattService gattService : gattServices) {

        String uuid = gattService.getUuid().toString();

        List<BluetoothGattCharacteristic> gattCharacteristics = gattService
                .getCharacteristics();
        if (uuid.equals("00001810-0000-1000-8000-00805f9b34fb")) {
            //  salida.append("Ecnontro");
            for (BluetoothGattCharacteristic gattCharacteristic : gattCharacteristics) {
                String uuid1 = gattCharacteristic.getUuid().toString();
                if (uuid1.equals("00002a35-0000-1000-8000-00805f9b34fb")) {
                    //     salida.append("Envio caracterisitca");
                    mensaje(getResources().getString(R.string.Espere_res));
                    mBluetoothLeService.setCharacteristicNotification(
                            gattCharacteristic, true);
                }
            }
        }
    }
}

To set UUID

BluetoothLeService.ACTION_GATT_SERVICES_DISCOVERED.equals(action)) {

            // Show all the supported services and characteristics on the user interface.
            displayGattServicesService(mBluetoothLeService.getSupportedGattServices());

Use BleGatt Example https://github.com/googlesamples/android-BluetoothLeGatt

Answer 2

我解决了问题！在调用setNotifyListener跟踪脉搏值变化之前，您必须将用户信息（年龄、体重）写入适当的特征，因为没有这个小米手环不会开始测量。

使用小米手环和 BLE 测量心率

Heart Rate measuring using Xiaomi MiBand and BLE

java

android

bluetooth-lowenergy