ble编程－外设发送数据到中心

ゞ浴缸里的玫瑰 2021-11-02 06:44 244阅读 0赞

一、外设

1.在外设的.h文件中定义如下

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1 //周边管理者 2 3 @property (nonatomic , strong) CBPeripheralManager *peripheralManager; 4 5 // 中心 6 7 @property (nonatomic,strong) CBCentral *central; 8 9 // 特征 10 11 @property (nonatomic , strong) CBMutableCharacteristic *customCharacteristic; 12 13 // 服务 14 15 @property (nonatomic , strong) CBMutableService *customService; 16 17 // 向中心发送的数据 18 19 @property (strong, nonatomic) NSData *dataToSend; 20 21 @property (nonatomic, readwrite) NSInteger sendDataIndex;

2.然后在.m文件中进行如下操作

2.1在viewDidLoad方法中初始化外设和要发送的数据

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1 // 初始化外设 2 self.peripheralManager = [[CBPeripheralManager alloc] initWithDelegate:self queue:nil]; 3 // 初始化数据 4 self.dataToSend = [@"snadjfkhaw加大困难的是咖啡euijferlfmn ksxncjxznvjeajfrnjadnfjasfndsafnjsadkfnjsa" dataUsingEncoding:NSUTF8StringEncoding];

2.2 Peripheral Manager被创建，状态改变时调用

CBPeripheralManagerStatePoweredOff 设备关闭状态

CBPeripheralManagerStateUnauthorized 未授权

CBPeripheralManagerStateUnsupported 您的设备不支持蓝牙4.0

CBPeripheralManagerStateResetting 重置状态

CBPeripheralManagerStateUnknown 未知状态

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1 - (void)peripheralManagerDidUpdateState:(CBPeripheralManager *)peripheral 2 3 { 4 5 switch (peripheral.state) { 6 7 case CBPeripheralManagerStatePoweredOn: 8 9 NSLog(@"蓝牙设备已经打开，可以扫描外设"); 10 11 [self setupService]; 12 13 break; 14 15 default: 16 17 NSLog(@"外设改变状态"); 18 19 break; 20 21 } 22 23 } 24 25 - (void)setupService 26 27 { 28 29 //creates the characteristic UUID 30 31 CBUUID *characteristicUUID = [CBUUID UUIDWithString:kCharacteristicUUID]; 32 33 //create the characteristic 34 35 self.customCharacteristic = [[CBMutableCharacteristic alloc] initWithType:characteristicUUID 36 37 properties:CBCharacteristicPropertyNotify 38 39 value:nil 40 41 permissions:CBAttributePermissionsReadable]; 42 43 //create the service UUID 44 45 CBUUID *servieceUUID = [CBUUID UUIDWithString:kServiceUUID]; 46 47 //creates the service and adds the charecteristic to it 48 49 self.customService = [[CBMutableService alloc] initWithType:servieceUUID primary:YES]; 50 51 //sets the characteristics for this service 52 53 [self.customService setCharacteristics:@[self.customCharacteristic]]; 54 55 // And add it to the peripheral manager 56 57 [self.peripheralManager addService:self.customService]; 58 59 }

2.3 当你执行addService方法后执行如下回调

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1 - (void)peripheralManager:(CBPeripheralManager *)peripheral didAddService:(CBService *)service error:(NSError *)error { 2 if (error != nil) { 3 NSLog(@"%s,error = %@",__PRETTY_FUNCTION__, error.localizedDescription); 4 } else { 5 //starts advertising the service 6 [self.peripheralManager startAdvertising:@{CBAdvertisementDataLocalNameKey:@"服务门店", 7 CBAdvertisementDataServiceUUIDsKey:@[[CBUUID UUIDWithString:kServiceUUID]]}]; 8 9 } 10 }

2.4 central订阅了characteristic的值，当更新值的时候peripheral会调用

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1 - (void)peripheralManager:(CBPeripheralManager *)peripheral central:(CBCentral *)central didSubscribeToCharacteristic:(CBCharacteristic *)characteristic 2 { 3 self.central = central; 4 if (_lastDeviceUUID == central.identifier) { 5 return; 6 } 7 _lastDeviceUUID = central.identifier; 8 self.sendDataIndex = 0; 9 [self sendData]; 10 } 11 12 13 #pragma mark - 向客户端发消息 14 - (void)sendData { 15 16 // 标记是否为最后一次发送 17 static BOOL sendingEOM = NO; 18 // 1. 如果是最后一次发送 19 if (sendingEOM) { 20 // 只发送 "EOM" 表示结束 21 BOOL didSend = [self.peripheralManager updateValue:[@"EOM" dataUsingEncoding:NSUTF8StringEncoding] forCharacteristic:self.customCharacteristic onSubscribedCentrals:@[self.central]]; 22 23 // 1.1. 最后一次发送成功 24 if (didSend) { 25 sendingEOM = NO; 26 NSLog(@"Sent: EOM"); 27 } 28 return; 29 } 30 // 2. 不是最后一次发送,且数据为空，则返回 31 if (self.sendDataIndex >= self.dataToSend.length) { 32 return; 33 } 34 // 3. 数据尚未发送完成，继续发送直到完成 35 BOOL didSend = YES; 36 while (didSend) { 37 // 3.1. 计算剩余多大数据量需要发送 38 NSInteger amountToSend = self.dataToSend.length - self.sendDataIndex; 39 // 不能大于20个字节 40 if (amountToSend > NOTIFY_MTU) 41 amountToSend = NOTIFY_MTU; 42 // 3.2. copy出我们想要发送的数据 43 NSData *chunk = [NSData dataWithBytes:self.dataToSend.bytes+self.sendDataIndex length:amountToSend]; 44 // 3.3. 发送 45 didSend = [self.peripheralManager updateValue:chunk forCharacteristic:self.customCharacteristic onSubscribedCentrals:@[self.central]]; 46 // 3.4. 如果没有发送成功，重新发送 47 // If it didn't work, drop out and wait for the callback 48 if (!didSend) { 49 NSLog(@"SEND ERROR"); 50 return; 51 } 52 NSString *stringFromData = [[NSString alloc] initWithData:chunk encoding:NSUTF8StringEncoding]; 53 NSLog(@"Sent: %@", stringFromData); 54 // 3.5. 发送成功，修改已经发送成功数据index值 55 self.sendDataIndex += amountToSend; 56 // 3.6. 如果是最后一次需要发送 57 if (self.sendDataIndex >= self.dataToSend.length) { 58 // 3.6.1. 把 标识是否为最后一次发送 改为YES 59 sendingEOM = YES; 60 // 3.6.2. 发送 61 BOOL eomSent = [self.peripheralManager updateValue:[@"EOM" dataUsingEncoding:NSUTF8StringEncoding] forCharacteristic:self.customCharacteristic onSubscribedCentrals:@[self.central]]; 62 if (eomSent) { 63 // 3.6.3. 发送成功，则我们已经完成这个功能 64 sendingEOM = NO; 65 NSLog(@"Sent: EOM"); 66 } 67 return; 68 } 69 } 70 }

2.5 peripheral再次准备好发送Characteristic值的更新时候调用

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1 - (void)peripheralManagerIsReadyToUpdateSubscribers:(CBPeripheralManager *)peripheral 2 { 3 [self sendData]; 4 }

2.6 当central取消订阅characteristic这个特征的值后调用方法

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1 - (void)peripheralManager:(CBPeripheralManager *)peripheral central:(CBCentral *)central didUnsubscribeFromCharacteristic:(CBCharacteristic *)characteristic 2 { 3 NSLog(@"central=%@设备拒绝请求,%s,",central,__PRETTY_FUNCTION__); 4 }

二、中心

1.在中心的.h文件中定义如下

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1 /** 2 * 中心角色 3 */ 4 @property (nonatomic , strong) CBCentralManager *centralManager; 5 @property (nonatomic , strong) CBPeripheral *peripheral; 6 @property (nonatomic, strong) CBCharacteristic *character; 7 @property (nonatomic , strong) NSMutableData *data;

2.然后在.m文件中进行如下操作

2.1在viewDidLoad方法中初始化中心和要发送的数据

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1     // 1.建立中心角色，queue为执行队列，默认为主线程 2 self.centralManager = [[CBCentralManager alloc] initWithDelegate:self queue:nil]; 3 // 2.初始化显示控件 4 [self setupUI]; 5 // 3.初始化data 6 _data = [[NSMutableData alloc] init];

2.2 CBCentralManagerDelegate代理方法

回调，返回当前设备蓝牙状态

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1 #pragma mark - CBCentralManagerDelegate 2 #pragma mark 回调，返回当前设备蓝牙状态 3 - (void)centralManagerDidUpdateState:(CBCentralManager *)central { 4 5 switch (central.state) { 6 case CBCentralManagerStatePoweredOn:{ 7 // 扫描外设(discover) 8 _messageLabel.text = @"蓝牙设备已经打开，可以扫描外设"; 9 [self scan]; 10 } 11 break; 12 default: 13 break; 14 } 15 } 16 17 #pragma mark - 扫描外设(discover) 超时停止扫描 18 - (void)scan{ 19 /** 20 * 第一个参数指定了要搜寻的服务，如果传nil，表示搜寻搜所有的服务 21 * 第二个参数指定了CBCentralManagerScanOptionAllowDuplicatesKey为已发现的设备是否重复扫描， 22 * 如果是同一设备不会多次回调。 23 */ 24 [self.centralManager scanForPeripheralsWithServices:@[[CBUUID UUIDWithString:kServiceUUID]] options:@{CBCentralManagerScanOptionAllowDuplicatesKey:@YES}]; 25 26 } 27

发现外设，回调

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1 - (void)centralManager:(CBCentralManager *)central didDiscoverPeripheral:(CBPeripheral *)peripheral advertisementData:(NSDictionary *)advertisementData RSSI:(NSNumber *)RSSI { 2 3 NSLog(@"找到了服务:%@,信号质量:%@",advertisementData,RSSI); 4 self.serviceName = [advertisementData objectForKey:@"kCBAdvDataLocalName"]; 5 6 if (self.peripheral != peripheral) { 7 self.peripheral = peripheral; 8 NSLog(@"开始连接blueServer:%@",peripheral); 9 [self.centralManager connectPeripheral:self.peripheral options:nil]; 10 } 11 }

连接失败，回调

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1 - (void)centralManager:(CBCentralManager *)central didFailToConnectPeripheral:(CBPeripheral *)peripheral error:(NSError *)error { 2 NSLog(@"Failed to connect to %@. (%@)", peripheral, [error localizedDescription]); 3 [self cleanup]; 4 }

连接成功，回调

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1 - (void)centralManager:(CBCentralManager *)central didConnectPeripheral:(CBPeripheral *)peripheral { 2 //因为一个peripheral可能不止提供一个service 3 NSLog(@"连接成功,进一步获取peripheral的service"); 4 [self.centralManager stopScan]; 5 6 // 每过 0.1 秒钟执行一次 readBLEServiceRSSI 方法 7 self.timer = [NSTimer scheduledTimerWithTimeInterval:1.0 target:self selector:@selector(readBLEServiceRSSI) userInfo:nil repeats:YES]; 8 9 [self.data setLength:0]; 10 11 // 设置代理 12 self.peripheral.delegate = self; 13 14 //查询符合条件的外设 15 [self.peripheral discoverServices:@[[CBUUID UUIDWithString:kServiceUUID]]]; 16 } 17 18

失去连接，回调

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2.3 CBPeripheralDelegate代理方法

读取到RSSI值后的操作

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1 - (void)peripheralDidUpdateRSSI:(CBPeripheral *)peripheral error:(NSError *)error { 2 NSLog(@"%s,%@",__PRETTY_FUNCTION__,peripheral); 3 int rssi = abs([peripheral.RSSI intValue]); 4 CGFloat ci = (rssi - 49) / (10 * 4.); 5 6 self.messageLabel.text = [NSString stringWithFormat:@"发现BLT4.0热点:%@,距离:%.1fm",self.serviceName,pow(10,ci)]; 7 }

找到我们刚刚指定的服务

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1 - (void)peripheral:(CBPeripheral *)peripheral didDiscoverServices:(NSError *)error { 2 if (error) { 3 NSLog(@"%s,error=%@", __PRETTY_FUNCTION__, error.localizedDescription); 4 [self cleanup]; 5 return; 6 } else { 7 for (CBService *service in peripheral.services) { 8 NSLog(@"发现UUID=%@的服务",service.UUID); 9 NSLog(@"开始检测这个服务的特征码..."); 10 if ([service.UUID isEqual:[CBUUID UUIDWithString:kServiceUUID]]) { 11 [self.peripheral discoverCharacteristics:@[[CBUUID UUIDWithString:kCharacteristicUUID]] forService:service]; 12 } 13 } 14 } 15 }

如果一个特征被检测到,回调

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1 - (void)peripheral:(CBPeripheral *)peripheral didDiscoverCharacteristicsForService:(CBService *)service error:(NSError *)error { 2 if (error) { 3 NSLog(@"%s,%@",__PRETTY_FUNCTION__,error); 4 [self cleanup]; 5 return; 6 } else { 7 if ([service.UUID isEqual:[CBUUID UUIDWithString:kServiceUUID]]) { 8 for (CBCharacteristic *characteristic in service.characteristics) { 9 if ([characteristic.UUID isEqual:[CBUUID UUIDWithString:kCharacteristicUUID]]) { 10 [peripheral setNotifyValue:YES 11 forCharacteristic:characteristic]; 12 self.character=characteristic; 13 } 14 } 15 } 16 } 17 }

处理蓝牙发过来的数据

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1 - (void)peripheral:(CBPeripheral *)peripheral didUpdateValueForCharacteristic:(CBCharacteristic *)characteristic error:(NSError *)error { 2 if (error) { 3 NSLog(@"didUpdateValueForCharacteristic - Error discovering characteristics: %@", [error localizedDescription]); 4 return; 5 } 6 NSString *stringFromData = [[NSString alloc] initWithData:characteristic.value encoding:NSUTF8StringEncoding]; 7 // 如果我们获得了所有的数据 8 if ([stringFromData isEqualToString:@"EOM"]) { 9 // 显示数据 10 [self alarm:self.data]; 11 // 取消订阅 12 [peripheral setNotifyValue:NO forCharacteristic:characteristic]; 13 // 让中心失去和设备的连接 14 [self.centralManager cancelPeripheralConnection:peripheral]; 15 } 16 // 否则，拼接数据 17 [self.data appendData:characteristic.value]; 18 // Log it 19 NSLog(@"Received: %@", stringFromData); 20 }

外围设备是否被注销

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1 - (void)peripheral:(CBPeripheral *)peripheral didUpdateNotificationStateForCharacteristic:(CBCharacteristic *)characteristic error:(NSError *)error { 2 if (error) { 3 NSLog(@"%s,%@",__PRETTY_FUNCTION__,error.localizedDescription); 4 } 5 if (![characteristic.UUID isEqual:[CBUUID UUIDWithString:kCharacteristicUUID]]) { 6 return; 7 } 8 //已经发送通知 9 if (characteristic.isNotifying) { 10 NSLog(@"Notification began on %@",characteristic); 11 } else { 12 //Notification has stopped 13 //so disconnect from the peripheral 14 NSLog(@"Notification stopped on %@ Disconnecting",characteristic); 15 [self.centralManager cancelPeripheralConnection:self.peripheral]; 16 } 17 }

2.4 出现错误或者结束连接时调用（私有方法）

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1 #pragma mark - Call this when things either go wrong, or you're done with the connection. 2 - (void)cleanup { 3 // Don't do anything if we're not connected 4 if (!self.peripheral.isConnected) { 5 return; 6 } 7 // See if we are subscribed to a characteristic on the peripheral 8 if (self.peripheral.services != nil) { 9 for (CBService *service in self.peripheral.services) { 10 if (service.characteristics != nil) { 11 for (CBCharacteristic *characteristic in service.characteristics) { 12 if ([characteristic.UUID isEqual:[CBUUID UUIDWithString:kCharacteristicUUID]]) { 13 if (characteristic.isNotifying) { 14 // It is notifying, so unsubscribe 15 [self.peripheral setNotifyValue:NO forCharacteristic:characteristic]; 16 // And we're done. 17 return; 18 } 19 } 20 } 21 } 22 } 23 } 24 // If we've got this far, we're connected, but we're not subscribed, so we just disconnect 25 [self.centralManager cancelPeripheralConnection:self.peripheral]; 26 }

转载于:https://www.cnblogs.com/Free-Thinker/p/11213819.html

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