与 Arduino 的 C# 串行通信

Question

我正在从事一个项目，该项目涉及我的客户端软件通过串行通信将数据发送到 Arduino 微 Controller AtMega32U4。到目前为止，我已经浏览了许多已回答的问题，但没有一个是针对我的问题的。但是，我相信我的问题可能仅限于线程问题或 Arduino 自动重置问题。

代码 1:

public MainForm()
    {
        InitializeComponent();
        serialPort1.DataReceived += new SerialDataReceivedEventHandler(serialPort1_DataReceived);
        serialPort1.DtrEnable = true;
        //serialPort1.RtsEnable = true;
    }
private void button3_Click(object sender, EventArgs e)
    {
        // Disables button while processing
        button3.Enabled = false;

        GetDir dir = new App.GetDir();
        dir.getCoords(Origin.Text, Destination.Text, Application.StartupPath + @"\temp2.html", "temp2.xml");
        dataBrowser.Navigate(Application.StartupPath + @"\temp2.html");
        dataBrowser.Update();

        waypoints = dir.coordsLat.Length;
        counter = dir.coordsLat.Length;
        coords = new double[dir.coordsLat.Length, 2];

        for (int i = 0; i < counter; i++)
        {
            coords[i, 0] = (Convert.ToDouble(dir.coordsLat[i]));
            coords[i, 1] = (Convert.ToDouble(dir.coordsLon[i]));
        }

        //serialPort1.Close();
        //System.Threading.Thread.Sleep(1000);


        if (serialPort1.IsOpen && !doubleClick)
        {
            serialPort1.Close();
            System.Threading.Thread.Sleep(2000);
            try
            {
                serialPort1.Open();
            }
            catch (Exception exception)
            {
                MessageBox.Show(exception.Message, "Cannot open serial port");
            }
            System.Threading.Thread.Sleep(2000);
        }
        else
        {
            if (!serialPort1.IsOpen)
            {
                try
                {
                    serialPort1.Open();
                    doubleClick = true;
                }
                catch (Exception exception)
                {
                    MessageBox.Show(exception.Message, "Cannot open serial port");
                }
                System.Threading.Thread.Sleep(2000);
                serialPort1.Write("^");
                System.Threading.Thread.Sleep(1000);
                Console.WriteLine('^');
                //button3.Enabled = true;
            }
        }  
    }

    private void serialPort1_DataReceived(object sender, SerialDataReceivedEventArgs e)
    {
        //System.Threading.Thread.Sleep(1000);
        readData = serialPort1.ReadLine();
        Console.WriteLine(readData);
        // If microcontroller sends "&", it is ready to receive next piece of data
        if (readData == "&")
        {
            sendRequest = true;
        }
        else
        {
            sendRequest = false;
        }

        // Write next piece of data to microcontroller if it is ready
        if (sendRequest)
        {
            this.BeginInvoke( new EventHandler (write_serialPort1));
        }
    }

在代码 1 的调试过程中，事件处理程序 (serialPort1_DataReceived) 永远不会被调用。在此过程中，由于控制台输出“^”两次，button3_click 以某种方式被调用了两次。之后，客户端因为没有收到任何东西而停止。请记住，Arduino 将在收到抑扬符 ('^') 后以与号 ('&') 响应。 Arduino 代码已经在 Arduino IDE 上进行了测试，看起来运行良好。我相信 button3_click 被调用两次的问题来自 button3_down 和 button3_up。

但是，我能够通过代码 2 绕过这个问题。但也遇到了另一堵墙。

代码 2:

 private void button3_Click(object sender, EventArgs e)
    {
        // Disables button while processing
        button3.Enabled = false;

        GetDir dir = new App.GetDir();
        dir.getCoords(Origin.Text, Destination.Text, Application.StartupPath + @"\temp2.html", "temp2.xml");
        dataBrowser.Navigate(Application.StartupPath + @"\temp2.html");
        dataBrowser.Update();

        waypoints = dir.coordsLat.Length;
        counter = dir.coordsLat.Length;
        coords = new double[dir.coordsLat.Length, 2];

        for (int i = 0; i < counter; i++)
        {
            coords[i, 0] = (Convert.ToDouble(dir.coordsLat[i]));
            coords[i, 1] = (Convert.ToDouble(dir.coordsLon[i]));
        }

        serialPort1.Close();

        try
        {
            serialPort1.Open();
        }
        catch (Exception exception)
        {
            MessageBox.Show(exception.Message, "Cannot open serial port");
        }

        if (serialPort1.IsOpen)
        {
            System.Threading.Thread.Sleep(2000);
            using (serialPort1)
            {
                serialPort1.Write("^");
                System.Threading.Thread.Sleep(1000);
                Console.WriteLine("^");
                serialPort1.Close();
                System.Threading.Thread.Sleep(5000);
            }
        }
        else
        {
            button3.Enabled = true;
        }

    }

    private void serialPort1_DataReceived(object sender, SerialDataReceivedEventArgs e)
    {
        //SerialPort sp = (SerialPort)sender;

        System.Threading.Thread.Sleep(10000);
        /*if (!serialPort1.IsOpen)
        {
            serialPort1.Close();
            System.Threading.Thread.Sleep(10000);
            serialPort1.Open();
            System.Threading.Thread.Sleep(10000);
        }*/
        //serialPort1.Open();
        //using (sp)
        using (serialPort1)
        {
            serialPort1.Open();
            System.Threading.Thread.Sleep(5000);
            readData = serialPort1.ReadExisting();
            Console.WriteLine(readData);
            // If microcontroller sends "&", it is ready to receive next piece of data
            if (readData == "&")
            {
                sendRequest = true;
            }
            else
            {
                sendRequest = false;
            }

            // Write next piece of data to microcontroller if it is ready
            if (sendRequest)
            {
                this.BeginInvoke(new EventHandler(write_serialPort1));
            }
        }
    }

在代码 2 中，事件处理程序确实被调用并且 button3_click 仅运行一次。但是当它尝试打开端口时，它会返回错误“Access to Port X denied”。此外，我希望我不必像这样关闭和打开端口，但是当调用事件处理程序时(在较早的代码中)它返回了 COM 端口未打开的错误。为了解决这个错误，我不得不在 button3_click 和事件处理期间关闭它并重新打开它。

在阅读了很多处理串行通信线程问题的问题后，我在代码中添加了很多延迟。我什至尝试过延迟一分钟，希望线程结束以解决问题。但是，那里没有运气。

我还在 MainForm 设计器中指定了我的串行端口，而不是在代码中声明它(起初我同时做了这两个并意识到这是多余的)。我不确定这是否会导致问题，但我已经看到使用这两种方法的示例。

最后，它绝对可以在每次建立串行连接(例如打开和关闭端口)时处理 Arduino 自动重置。综上所述，似乎是通过串口发送数据，但无法读取串口传入的数据。

感谢您阅读本文，如果有人能为我指出正确的方向，我们将不胜感激。

编辑#1:即使在代码 1 中使用了 BeginInvoke 之后，它仍然会死锁，因为从未调用过事件处理程序。

编辑#2:根据新手的建议对代码 1 进行编辑。

编辑 #3: 添加了主窗体初始化并将代码 1 更新为当前状态。

编辑 #4: 删除(注释掉)事件处理程序中的 sleep 。我在事件处理程序期间正在 sleep ，因此我无法收到微 Controller 发送给我的任何信息。代码现在可以正常工作了。

Answer 1

Make sure you are using COM1, if you do not COM1 serial port, change through Computer -> Device Manager -> Ports (COM & LPT) -> Select the COM to be changed -> Port Settings -> Advanced -> ComPort Number -> select COM1.

Make sure that you have installed jumper / connect with a screwdriver between pin2 and pin3 of COM1.

Add button1 and textBox1 to Form and run this program

using System;
using System.Windows.Forms;
using System.IO.Ports;
using System.Threading;
using System.Text;

namespace WindowsFormsApplication1 {
    public partial class Form1 : Form {

        const int MAX_BUFFER = 100;

        int i = 0;
        byte[] DataReceived = new byte[MAX_BUFFER];
        SerialPort serialPort = new SerialPort();

        public Form1() {
            InitializeComponent();
            serialPort.DataReceived += new SerialDataReceivedEventHandler(serialPort_DataReceived);
        }

        void serialPort_DataReceived(object sender, SerialDataReceivedEventArgs e) {
            // wait data ready
            Thread.Sleep(500);

            // while data ready in buffer
            while (serialPort.IsOpen && serialPort.BytesToRead > 0) {
                // read data serial
                DataReceived[i] = Convert.ToByte(serialPort.ReadByte());

                // counter data
                i++;

                // reset conter if more then maxvalue
                if (i >= MAX_BUFFER) {
                    i = 0;
                }
            }

            if (i == 1 && DataReceived[0] == ASCIIEncoding.ASCII.GetBytes("^")[0]) {
                this.textBox1.Invoke(new Action(() => {
                    this.textBox1.Text = ASCIIEncoding.ASCII.GetString(DataReceived, 0, 1);

                }));
            }

        }

        public void InitSerialPort() {
            serialPort.PortName = "COM1";
            serialPort.BaudRate = 9600;
            serialPort.Parity = Parity.None;
            serialPort.DataBits = 8;
            serialPort.StopBits = StopBits.One;
            serialPort.ReceivedBytesThreshold = 1;
        }

        private void Form1_Load(object sender, EventArgs e) {
            // initialize serial port
            InitSerialPort();

            // assure port is closed before open it
            if (serialPort != null && serialPort.IsOpen) {
                serialPort.Close();
            }
            serialPort.Open();
        }

        private void button1_Click(object sender, EventArgs e) {
            if (serialPort.IsOpen) {
                serialPort.Write("^");
                // wait data sent
                Thread.Sleep(500);
            }
        }
    }
}