Win IOT上的NFC阅读器:Pin'目前以不兼容的共享模式打开

时间:2017-11-15 12:33:05

标签: c# windowsiot

我正在研究基于在Rasperry PI 3上运行的Windows 10 IoT的NFC阅读器项目。

我使用这里找到的库Mfrc522lib.cs:RFID RC522 Raspberry PI 2 Windows IOT。 我使用异步任务等待卡。它第一次扫描完美,但是当我再次启动任务时(用于按钮测试puprose)。 我明白了:

Pin ' is currently opened in an incompatible sharing mode. Make sure this pin is not already in use by this application or another Application

有什么想法吗?

public MainPage()
{
    this.InitializeComponent();
    startNFC();
}

public void startNFC()
{
    var read = ReadNFCAsync();

    Windows.ApplicationModel.Core.CoreApplication.MainView.CoreWindow.Dispatcher.RunAsync(CoreDispatcherPriority.Normal,
        () =>
        {
            // Your UI update code goes here!
            this.serial.Text = "Klar for å lese kortet ditt";
            this.statusline.Fill = new SolidColorBrush(Colors.Green);
        });
    read.ContinueWith(prev => {
        Windows.ApplicationModel.Core.CoreApplication.MainView.CoreWindow.Dispatcher.RunAsync(CoreDispatcherPriority.Normal,
            () =>
            {
                // Your UI update code goes here!
                this.serial.Text = prev.Result.ToString();
                this.statusline.Fill = new SolidColorBrush(Colors.Orange);
            });
    });
}

public static async Task<String> ReadNFCAsync()
{
    await Task.Delay(1000); 
    var mfrc  = new Mfrc522();

    await mfrc.InitIO();

    while (true)
    {
        if (mfrc.IsTagPresent())
        {

            var uid = mfrc.ReadUid();
            var serial= uid.ToString();

            mfrc.HaltTag();
            return serial;

        }
    }
}

private async void Button_Click(object sender, RoutedEventArgs e)
{
    startNFC();
}

1 个答案:

答案 0 :(得分:0)

由于初始化GPIO引脚而导致的此问题正在使用中。因为每次单击按钮时都会执行以下行:

await mfrc.InitIO();

要解决此问题,您可以像这样编辑代码:

    private Mfrc522 mfrc = new Mfrc522();

    public static bool IsGpioInitialized = false;

    public async Task ReadNFCAsync()
    {
        if (!IsGpioInitialized)
        {
            await mfrc.InitIO();
            IsGpioInitialized = true;
        }
    }