如何在iOS Swift中将值写入BLE设备的characteristc

我正在使用iOS BLE应用为手机充电。我做了一切纠正以发现特征。首先扫描外围设备并连接到它。发现具有通知和写入但没有响应属性的服务（FFB0）和特征（FFB1，FFB2）。

我找到了客户端特征配置描述符。我想将命令发送到PCB以解锁以进行充电我想向FFB2特性写入值，但外设没有响应。这是我的代码。

我已经搜索了与此相关的所有内容，但没有找到任何解决方案。如果有人对此问题提供了解决方案，它将对我有所帮助。

这是客户提供的文件：

每个PCB上都有一个BLE4.0蓝牙模块，每个蓝牙模块都有一个12字节长的地址代码，PCB数据通道，服务UUID是OxFFBO，包括两个特征值，分别是OxFFBI和OxFFB2，通信长度数据为1--20字节。OxFFB1是APP数据下载的通道，OxFBB2是Bluetooth上载数据的通道。

开机进入空闲模式，在空闲模式下，两个指示灯将闪烁，它将向手机发送一个ID码（一个字节），手机中的APP将获取一个ID码（一个字节）。可以通过电话设置来设置ID码。这意味着通过ID码发送相应的解锁指令。

解锁指令为0x55,0xe1，（ID0 + 1），time，以下为解锁指令说明：

ID0是一个ID码，“时间”是用户解锁时间（5-120分钟），请注意它是二进制到十六进制的转换，时间== 5表示5分钟，时间== 6表示6分钟，时间== A表示10分钟，依此类推。如果PCB的ID0为0xff，则解锁pcb 60min为：0x55,0xe1,0x00,0x3c; 如果PCB的ID0为0x05，则解锁pcb 10分钟为：0x55、0xe1、0x06、0x0a

当PCB上的MCU收到解锁指令时，它将开始打开输出并计时。计时时间到后，系统再次进入空闲模式。在空闲模式下，长按此键可进入关机睡眠时间模式。

uart的波特率设置为9,600。APP发送给MCU的查询命令是0x55 0x01 MCU应该回复APP的信息格式：0x55、0x02，bat_level，xH，XL（xH XL表示电池的当前电压值，xH-表示高8位，并且XL--代表低8位）

import CoreBluetooth

let batteryServiceCBUUID = CBUUID(string: "FFB0")
let batteryServiceRequestCBUUID = CBUUID(string: "FFB1")
let batteryServiceRequestCBUUID2 = CBUUID(string: "FFB2")

 class ChargingViewController: UIViewController , CBPeripheralDelegate 
 ,CBCentralManagerDelegate {    

  override func viewDidLoad() {
    super.viewDidLoad()
 centralManager = CBCentralManager(delegate: self, queue: nil, options: nil)  
 }
 func centralManagerDidUpdateState(_ central: CBCentralManager) {

    switch central.state {
    case .unknown:
        print("central.state is .unknown")
    case .resetting:
        print("central.state is .resetting")
    case .unsupported:
        print("central.state is .unsupported")
    case .unauthorised:
        print("central.state is .unauthorised")
    case .poweredOff:
        print("central.state is .poweredOff")
    case .poweredOn:


        centralManager.scanForPeripherals(withServices: [batteryServiceCBUUID])

        print("central.state is .poweredOn")
    @unknown default:
        fatalError()
    }

    print("state: \(central.state)")

 }
 func centralManager(_ central: CBCentralManager, didDiscover peripheral: CBPeripheral, 
 advertisementData: [String : Any], rssi RSSI: NSNumber) {

    print(peripheral)
    batteryServicePeripheral = peripheral
    batteryServicePeripheral.delegate = self
    centralManager.stopScan()
    centralManager.connect(batteryServicePeripheral)

 }
  func centralManager(_ central: CBCentralManager, didConnect peripheral: CBPeripheral) {

    print("Connected=======>\(String(describing: batteryServicePeripheral))")
    batteryServicePeripheral.delegate = self
    batteryServicePeripheral.discoverServices([batteryServiceCBUUID])

}

func centralManager(_ central: CBCentralManager, didFailToConnect peripheral: CBPeripheral, 
 error: Error?) {

    print("Fail To Connect=======>\(String(describing: error))")
}


func centralManager(_ central: CBCentralManager, didDisconnectPeripheral peripheral: 
CBPeripheral, error: Error?) {

    if error == nil {

        print("Disconnected========>\(peripheral)")
    }else {

        print("Disconnected========>\(String(describing: error))")
    }
 }
// MARK: -  CBPeripheral Delegate Methods

func peripheral(_ peripheral: CBPeripheral, didDiscoverServices error: Error?) {

    guard let services = peripheral.services else { return }

    for service in services {

        print("SPAKA:PERIPHERALSERVICES============>\(service)")
        peripheral.discoverCharacteristics(nil, for: service)

    }

}

func peripheral(_ peripheral: CBPeripheral, didDiscoverCharacteristicsFor service: CBService, error: Error?) {

    if let characteristics = service.characteristics {
        //else { return }

        for characteristic in characteristics {

            print(characteristic)


            if characteristic.uuid == batteryServiceCBUUID {

               peripheral.setNotifyValue(true, for: characteristic)

            }

            if characteristic.uuid == batteryServiceRequestCBUUID2 {

                batteryCharacteristics = characteristic


                let str1 = "55e100"
                let data = String(format: "%@%@",str1,hexTimeForChar)

                guard let valueString = data.data(using: String.Encoding.utf8)  else 
    {return}



                peripheral.writeValue(valueString, for: characteristic , type: 
        CBCharacteristicWriteType.withoutResponse)
                print("Value String===>\(valueString.debugDescription)")
                peripheral.setNotifyValue(true, for: characteristic)

            }

        }
    }
    peripheral.discoverDescriptors(for: batteryCharacteristics)
}


func peripheral(_ peripheral: CBPeripheral, didWriteValueFor characteristic: CBCharacteristic, error: Error?) {

    if error == nil {
        print("Message sent=======>\(String(describing: characteristic.value))")
    }else{

        print("Message Not sent=======>\(String(describing: error))")
    }




}

func peripheral(_ peripheral: CBPeripheral, didUpdateNotificationStateFor characteristic: 
CBCharacteristic, error: Error?) {

    if error == nil {
        print("SPAKA : IS NOTIFYING UPDATED STATE ======>\(characteristic.isNotifying)")
        print("SPAKA : UPDATED DESCRIPTION ======>\(String(describing: 
 characteristic.description))")


    }else{
        print("SPAKA : ERRORUPDATEDNOTIFICATION\(String(describing: error))")
    }


}


func peripheral(_ peripheral: CBPeripheral, didUpdateValueFor characteristic: CBCharacteristic, error: Error?) {

    print("SPAKA: UPDATED VALUE RECEIVED========>\(String(describing: characteristic.value))")
    print("characteristic UUID: \(characteristic.uuid), value: \(characteristic.value)")

    guard let str = characteristic.value else { return  }

    if let string = String(bytes: str, encoding: .utf8) {
        print("SPAKA==========>:::\(string)")
    } else {
        print("not a valid UTF-8 sequence")
    }



}

func peripheral(_ peripheral: CBPeripheral, didDiscoverDescriptorsFor characteristic: CBCharacteristic, error: Error?) {

    guard let desc = batteryCharacteristics.descriptors else { return }


    for des in desc {

        print("BEGIN:SPAKA DESCRIPTOR========>\(des)")
        discoveredDescriptor = des

        print("Descriptor Present Value and uuid: \(des.uuid), value: \(String(describing: des.value))")
        peripheral.readValue(for: discoveredDescriptor)


    }


}

func peripheral(_ peripheral: CBPeripheral, didWriteValueFor descriptor: CBDescriptor, error: Error?) {
    if let error = error {
        print("Failed… error: \(error)")
        return
    }

    print("Descriptor Write Value uuid: \(descriptor.uuid), value: \(String(describing: descriptor.value))")
}

func peripheral(_ peripheral: CBPeripheral, didUpdateValueFor descriptor: CBDescriptor, error: Error?) {

    if let error = error {
        print("Failed… error: \(error)")
        return
    }

    print("Descriptor Updated Value uuid: \(descriptor.uuid), value: \(String(describing: descriptor.value))")

}
}