BLE掃描未知服務

Question

我正在嘗試編寫一個玩具應用程序來加速BLE。我有一個我想掃描其服務的外圍設備（它是一個Tile）。但是，我不知道它提供的是什麼服務（並且我在產品的技術規範中沒有看到這一點）。所以，我從藍牙規格中獲得了list of services，並試圖掃描所有這些規格。我只是假設這份清單是詳盡的，因爲它沒有說這種或那種方式。

這裏是我的代碼：

- (void)viewDidLoad { 
    [super viewDidLoad];  

    // Scan for all available CoreBluetooth LE devices 
    _services = @[[CBUUID UUIDWithString:@"1811"], 
        [CBUUID UUIDWithString:@"1815"], 
        [CBUUID UUIDWithString:@"180F"], 
        [CBUUID UUIDWithString:@"1810"], 
        [CBUUID UUIDWithString:@"181B"], 
        [CBUUID UUIDWithString:@"181E"], 
        [CBUUID UUIDWithString:@"181F"], 
        [CBUUID UUIDWithString:@"1805"], 
        [CBUUID UUIDWithString:@"1818"], 
        [CBUUID UUIDWithString:@"1816"], 
        [CBUUID UUIDWithString:@"180A"], 
        [CBUUID UUIDWithString:@"181A"], 
        [CBUUID UUIDWithString:@"1800"], 
        [CBUUID UUIDWithString:@"1801"], 
        [CBUUID UUIDWithString:@"1808"], 
        [CBUUID UUIDWithString:@"1809"], 
        [CBUUID UUIDWithString:@"180D"], 
        [CBUUID UUIDWithString:@"1823"], 
        [CBUUID UUIDWithString:@"1812"], 
        [CBUUID UUIDWithString:@"1802"], 
        [CBUUID UUIDWithString:@"1821"], 
        [CBUUID UUIDWithString:@"1820"], 
        [CBUUID UUIDWithString:@"1803"], 
        [CBUUID UUIDWithString:@"1819"], 
        [CBUUID UUIDWithString:@"1807"], 
        [CBUUID UUIDWithString:@"1825"], 
        [CBUUID UUIDWithString:@"180E"], 
        [CBUUID UUIDWithString:@"1822"], 
        [CBUUID UUIDWithString:@"1806"], 
        [CBUUID UUIDWithString:@"1814"], 
        [CBUUID UUIDWithString:@"1813"], 
        [CBUUID UUIDWithString:@"1824"], 
        [CBUUID UUIDWithString:@"1804"], 
        [CBUUID UUIDWithString:@"181C"], 
        [CBUUID UUIDWithString:@"181D"]]; 

    CBCentralManager *centralManager = [[CBCentralManager alloc] initWithDelegate:self queue:nil]; 
    [centralManager scanForPeripheralsWithServices:_services options:nil]; 
    self.centralManager = centralManager; 
} 

- (IBAction)scanForDevices:(UIButton *)sender { 
    [_centralManager scanForPeripheralsWithServices:_services options:nil]; 
} 

// CBCentralManagerDelegate - This is called with the CBPeripheral class as its main input parameter. 
// This contains most of the information there is to know about a BLE peripheral. 
- (void)centralManager:(CBCentralManager *)central 
didDiscoverPeripheral:(CBPeripheral *)peripheral 
    advertisementData:(NSDictionary *)advertisementData 
        RSSI:(NSNumber *)RSSI 
{ 
    NSString *localName = [advertisementData objectForKey:CBAdvertisementDataLocalNameKey]; 
    if ([localName length] > 0) { 
     NSLog(@"Found the heart rate monitor: %@", localName); 
     [self.centralManager stopScan]; 
     _hRMPeripheral = peripheral; 
     peripheral.delegate = self; 
     [self.centralManager connectPeripheral:peripheral options:nil]; 
    } 
} 

// method called whenever the device state changes. 
- (void)centralManagerDidUpdateState:(CBCentralManager *)central 
{ 
    // Determine the state of the peripheral 
    if ([central state] == CBCentralManagerStatePoweredOff) { 
     NSLog(@"CoreBluetooth BLE hardware is powered off"); 
    } 
    else if ([central state] == CBCentralManagerStatePoweredOn) { 
     NSLog(@"CoreBluetooth BLE hardware is powered on and ready"); 
    } 
    else if ([central state] == CBCentralManagerStateUnauthorized) { 
     NSLog(@"CoreBluetooth BLE state is unauthorized"); 
    } 
    else if ([central state] == CBCentralManagerStateUnknown) { 
     NSLog(@"CoreBluetooth BLE state is unknown"); 
    } 
    else if ([central state] == CBCentralManagerStateUnsupported) { 
     NSLog(@"CoreBluetooth BLE hardware is unsupported on this platform"); 
    } 
} 

中僅有的日誌輸出，我得到的是這樣的：

CoreBluetooth BLE硬件上電，並準備

否則，應用程序運行良好。沒有錯誤或警告。但它永遠找不到外圍設備。

我在做什麼錯？是否有我應該掃描的不同服務？

謝謝！

EDIT
使用下面的建議，我使用LightBlue應用掃描的外圍。現在我知道，有一個使用此UUID所通知的服務：

84100CBF-D622-8FF7-C8B8-300FDB52B92D

我改變了我的陣列看起來像這樣：

_services = @[[CBUUID UUIDWithString:@"84100CBF-D622-8FF7-C8B8-300FDB52B92D"]]; 

但仍然沒有得到日誌中的輸出。我也嘗試通過nil但仍然沒有。

Answer 1

正如指出的Paulw，只是發送nil，而不是一個服務列表，你會得到在範圍內的所有外圍設備，無論服務（S），他們做廣告。

需要注意的是：

• 這隻會在前臺工作。背景掃描需要你提供服務掃描
• 在你的方法，它不可能列出所有服務。除了列出的簡短UUID服務（實際上是完整UUID的快捷方式）之外，設備可以通過任何「完整」UUID通告服務。有2^128個可能的值...