Swift BLE 外设 writeValue 不起作用

Posted 2023-03-05

【中文标题】Swift BLE 外设 writeValue 不起作用

【英文标题】：Swift BLE peripheral writeValue is not working

【发布时间】：2015-03-07 01:55:31

【问题描述】：

我当前的代码是：

@IBAction func sendData(sender: UISwitch) 
    if advertisingSwitch.on 
        var parameter = NSInteger(45)
        let data = NSData(bytes: &parameter, length: 1)
        if let connectedPeripheral = discoveredPeripheral 
            println("========= In connected peripheral \(connectedPeripheral)")
            //println("========= Send data is \(currentSendData)")
            println("========= Characteristic is \(sendDataCharacteristic)")
            println("========= data length is \(data.bytes)")
            self.sendDataToCentral(connectedPeripheral, characteristic: sendDataCharacteristic!, data: data)
        
    


private func sendDataToCentral(peripheral: CBPeripheral, characteristic: CBCharacteristic, data: NSData) 
    println("data is \(data)")
    peripheral.writeValue(data, forCharacteristic: characteristic, type: CBCharacteristicWriteType.WithoutResponse)
    println("writed characteristic \(characteristic)")

当我检查外围设备时，它已连接显示：

BPeripheral: 0x1700ee980, identifier = E2377588-84CB-87ED-570A-B51614287B3C, name = TAv22u-FDF1, state = connected

特征是从已知 UUID 的服务扫描中获取。我确定我得到的特征具有“写”功能，即

<CBCharacteristic: 0x174086090, UUID = FFE9, properties = 0x8, value = (null), notifying = NO>

在我执行函数之后：

peripheral.writeValue(data, forCharacteristic: characteristic, type: CBCharacteristicWriteType.WithoutResponse)

特征中的值没有改变。我不知道我哪里错了。

【问题讨论】：

当您说值没有改变时，您如何验证这一点？从接收外围设备还是您只是在发送中心检查CBCharacteristic 的值？

您在peripheral:didWriteValueForCharacteristic:error:（CBPeripheralDelegate 方法）中遇到什么错误？

@Paulw11 我的意思是我的数据没有显示在接收外围设备中。我有一个可以更新屏幕数据的外围接收器。

@MichałCiuba 这个函数甚至没有被执行。

如果你写withoutResponse，peripheral:didWriteValueForCharacteristic:error:不应该被调用。试试withResponse？ sendDataCharacteristic是怎么设置的？

【参考方案1】：

peripheral.writeValue(data, forCharacteristic: characteristic, type: 
 CBCharacteristicWriteType.WithResponse)

尝试.withResponse 并检查外围设备的响应。