c#mono raspberry pi GPIO with Raspberry#獲取操作無效

Question

我正在嘗試使用 Raspberry# 庫在 Raspberry PI（開和關）上執行帶有 GPIO 引腳的基本任務。 根據github上的示例： https : //github.com/raspberry-sharp/raspberry-sharp-io/wiki/Raspberry.IO.GeneralPurpose

代碼：

        var led1 = ConnectorPin.P1Pin11.Output();
        var connection = new GpioConnection(led1);
        for (var i = 0; i < 100; i++)
        {
            connection.Toggle(led1);
            System.Threading.Thread.Sleep(250);
        }
        connection.Close();

在線var connection = new GpioConnection(led1); 我得到例外：

“由於對象的當前狀態，操作無效”

堆棧跟蹤

Unhandled Exception:
System.InvalidOperationException: Operation is not valid due to the current state of the object
at Raspberry.IO.GeneralPurpose.GpioConnectionDriver..ctor () [0x00000] in <filename unknown>:0
at Raspberry.IO.GeneralPurpose.GpioConnectionSettings.get_DefaultDriver () [0x00000] in <filename unknown>:0
at Raspberry.IO.GeneralPurpose.GpioConnectionSettings..ctor () [0x00000] in <filename unknown>:0
at Raspberry.IO.GeneralPurpose.GpioConnection..ctor (Raspberry.IO.GeneralPurpose.GpioConnectionSettings settings, IEnumerable`1 pins) [0x00000] in <filename unknown>:0
at Raspberry.IO.GeneralPurpose.GpioConnection..ctor (Raspberry.IO.GeneralPurpose.PinConfiguration[] pins) [0x00000] in <filename unknown>:0
at Hello.Program.Main (System.String[] args) [0x00000] in <filename unknown>:0
[ERROR] FATAL UNHANDLED EXCEPTION: System.InvalidOperationException: Operation is not valid due to the current state of the object
at Raspberry.IO.GeneralPurpose.GpioConnectionDriver..ctor () [0x00000] in <filename unknown>:0
at Raspberry.IO.GeneralPurpose.GpioConnectionSettings.get_DefaultDriver () [0x00000] in <filename unknown>:0
at Raspberry.IO.GeneralPurpose.GpioConnectionSettings..ctor () [0x00000] in <filename unknown>:0
at Raspberry.IO.GeneralPurpose.GpioConnection..ctor (Raspberry.IO.GeneralPurpose.GpioConnectionSettings settings, IEnumerable`1 pins) [0x00000] in <filename unknown>:0
at Raspberry.IO.GeneralPurpose.GpioConnection..ctor (Raspberry.IO.GeneralPurpose.PinConfiguration[] pins) [0x00000] in <filename unknown>:0
at Hello.Program.Main (System.String[] args) [0x00000] in <filename unknown>:0

我可以使用 Python 切換引腳狀態，因此設備沒有任何問題。

Answer 1

以 root 身份執行 Mono 程序。 普通用戶無法訪問 /dev/mem。

public GpioConnectionDriver() {

        using (var memoryFile = UnixFile.Open("/dev/mem", UnixFileMode.ReadWrite | UnixFileMode.Synchronized)) {
            gpioAddress = MemoryMap.Create(
                IntPtr.Zero, 
                Interop.BCM2835_BLOCK_SIZE,
                MemoryProtection.ReadWrite,
                MemoryFlags.Shared, 
                memoryFile.Descriptor,
                Interop.BCM2835_GPIO_BASE
            );
        }
    }

從這里解釋： http : //www.raspberrypi.org/forums/viewtopic.php? f=29&t= 22515

要打開 /dev/mem，您需要對設備文件的常規訪問權限和安全功能 CAP_SYS_RAWIO，或者是 root。 沒有辦法解決這個問題，因為對內存的完全訪問允許的不僅僅是 GPIO。 它具有巨大的安全隱患。

Answer 2

你可以使用 Iot.Device.Bindings 包更好

https://docs.microsoft.com/fr-fr/dotnet/iot/tutorials/blink-led