alb技术笔记基于多线程方式的串行通信接口数据接收案例

        SerialPort com = new SerialPort();                  //实例化一个串口对象
        Thread t;                                           //定义一个线程字段
        private void Form1_Load(object sender, EventArgs e)
        {
            textBox1.ReadOnly = true;                       //文本框只读
            textBox1.ScrollBars = ScrollBars.Vertical;      //文本框支持垂直滚动条
            comboBox1.Items.Add("COM1");
            comboBox1.Items.Add("COM2");
            comboBox1.Items.Add("COM3");
            comboBox1.Items.Add("COM4");
            comboBox1.Items.Add("COM5");
            comboBox1.SelectedIndex = 2;

            comboBox2.Items.Add("4800");
            comboBox2.Items.Add("9600");
            comboBox2.Items.Add("19200");
            comboBox2.Items.Add("57600");
            comboBox2.Items.Add("115200");
            comboBox2.SelectedIndex = 1;

            comboBox3.Items.Add("6");
            comboBox3.Items.Add("7");
            comboBox3.Items.Add("8");
            comboBox3.SelectedIndex = 2;

            comboBox4.Items.Add("1");
            comboBox4.Items.Add("1.5");
            comboBox4.Items.Add("2");
            comboBox4.SelectedIndex = 0;
        }

        private void button1_Click(object sender, EventArgs e)
        {
            if (button1.Text == "打开串口")
            {
                com.PortName = comboBox1.Text;                      //选择串口号
                com.BaudRate = int.Parse(comboBox2.Text);           //选择波特率
                com.DataBits = int.Parse(comboBox3.Text);           //选择数据位数
                com.StopBits = (StopBits)int.Parse(comboBox4.Text); //选择停止位数
                com.Parity = Parity.None;                           //选择是否奇偶校验

                try
                {
                    if (com.IsOpen)                                 //判断该串口是否已打开
                    {
                        com.Close();
                        com.Open();
                    }
                    else
                    {
                        com.Open();
                    }
                    t = new Thread(com_DataReceived);        //创建并启用数据接收线程
                    t.Start();
                }
                catch(Exception ex)
                {
                    MessageBox.ReferenceEquals("错误：" + ex.Message, "串口通信");
                }
                button1.Text = "关闭串口";
            }
            else if (button1.Text == "关闭串口")
            {
                com.Close();                        //关闭串口
                t.Abort();                          //终止线程
                button1.Text = "打开串口";
            }
        }

        private void com_DataReceived()
        {
            while (com.IsOpen)                                          //在串口已打开情况下读取数据
            {
                string strRcv = "";
                int count = com.BytesToRead;                            //获取串口缓冲器的字节数
                byte[] readBuffer = new byte[count];                    //实例化接收串口数据的数组
                if (count != 0)                                         //如果串口接收到数据
                {
                    strRcv = count.ToString() + " ";      
                    com.Read(readBuffer, 0, count);                     //从串口缓冲区读出数据到数组
                    for (int i = 0; i < readBuffer.Length; i++)         
                    {
                        strRcv += readBuffer[i].ToString("X2") + " ";   //16进制显示  
                    }
                    textBox1.Text += strRcv + "\r\n";

                    if (readBuffer[0] == 0xAF && readBuffer[3] == 0xFA) //判断数据的帧头和帧尾
                    {
                        Int32 ad = readBuffer[1];
                        double advalue;
                        ad <<= 8;
                        ad |= readBuffer[2];                            //从数据帧中将电压数据取出
                        advalue = ad;
                        advalue = (advalue * 3.3) / 32768;              //将数据换算为实际的电压值
                        label6.Text = advalue.ToString("F2") + " V";
                    }
                }
                Thread.Sleep(500);
            }