串口通信

• 1. 基本概念
• ２.C#代码实现串口通信
• 3. 资源下载地址

1. 基本概念

• 数据是串行发送的，比如RS232、RS422、RS485，一位一位地发送数据，就是串口通信。串口通信分为同步和异步。
• 串口通信要设置以下参数：
  • 串口号：com1，com2…
  • 波特率：9600，115200…
  • 数据位：8，7，6
  • 校验位：None，Even，Odd
  • 停止位：1，２
• 9针脚，2针脚收数据，3针脚发数据

２.C#代码实现串口通信

• 串口实例化
• 设置串口参数
• 打开串口
• 发送数据
• 接收数据（事件响应）
  

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.IO;
using System.IO.Ports;

namespace SerialPortCom
{
    public partial class SerialPortForm : Form
    {
        //public delegate void DEL(byte[] buffer);//定义了一个委托 DEL

        #region 接收数据事件响应
        /// <summary>
        /// 事件响应函数：每当有串口数据进入就响应
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        public void DataRecv(object sender, SerialDataReceivedEventArgs e)
        {
            int counts = sp.BytesToRead;
            byte[] buffer = new byte[counts];
            //读入（接收）数据
            sp.Read(buffer, 0, counts);

            //DEL changeTextDelegate = new DEL(ChangeText);//实例化委托 委托类型 DEL  把 changeText函数转为DEL类型的委托

            //显示(16进制/字符串)
            if (radioButtonString.Checked)//字符串
            {
                //textBoxRec.Invoke(changeTextDelegate, buffer);
                //匿名委托
                Invoke(new MethodInvoker(delegate ()
                {
                    textBoxRec.Text += Encoding.Default.GetString(buffer);
                    labelReceByte.Text = buffer.Length.ToString();
                }));
            }
            else//16进制
            {
                Invoke(new MethodInvoker(delegate()
                {
                        textBoxRec.Text += HexByteToString(buffer);
                        labelReceByte.Text = buffer.Length.ToString();
                 }));
                //textBoxRec.Invoke(changeTextDelegate, buffer);
            }               
        }
        #endregion

        #region 串口实例化
        SerialPort sp = new SerialPort();
        public SerialPortForm()
        {
            InitializeComponent();
        }
        #endregion

        #region 设置串口参数
        
        private void SerialPortForm_Load(object sender, EventArgs e)
        {
            string[] comNames = SerialPort.GetPortNames();
            for(int i=0; i < comNames.Length; i++)
            {
                comboBoxPortNum.Items.Add(comNames[i]);
            }
            if(comNames.Length>0)
            {
                comboBoxPortNum.SelectedIndex = 0;
            }
            comboBoxBaudRate.SelectedIndex = 1;
            comboBoxDataBit.SelectedIndex = 0;
            comboBoxCheckBit.SelectedIndex = 0;
            comboBoxStopBit.SelectedIndex = 0;
        }
        #endregion

        #region 打开串口
        private void buttonOpenPort_Click(object sender, EventArgs e)
        {
            if(!sp.IsOpen)
            {
                sp.PortName = comboBoxPortNum.Text;//配置串口号
                sp.BaudRate = Convert.ToInt32(comboBoxBaudRate.Text);//配置波特率
                sp.DataBits = Convert.ToInt32(comboBoxDataBit.Text);//配置数据位
                //两种string转枚举的方式
                sp.Parity = (Parity)Enum.Parse(typeof(Parity),comboBoxCheckBit.Text);//校验位
                sp.StopBits = (StopBits)Enum.Parse(typeof(StopBits), comboBoxStopBit.Text);
                //sp.StopBits = (StopBits)int.Parse(comboBoxStopBit.Text);//停止位
                sp.Open();//打开串口
                buttonOpenPort.Text = "关闭串口";
                buttonOpenPort.BackColor = Color.Green;

                sp.DataReceived += new SerialDataReceivedEventHandler(DataRecv);
            }
            else
            {
                sp.Close();//关闭窗口
                buttonOpenPort.Text = "打开串口";
                buttonOpenPort.BackColor = Color.White;
            }
        }

        #endregion

        #region 发送
        private void buttonSend_Click(object sender, EventArgs e)
        {
            if (sp.IsOpen)
            {
                byte[] buffer;
                if (radioButtonString.Checked)//字符串发送
                {
                    buffer = Encoding.Default.GetBytes(textBoxSend.Text);//string转ASCCII
                    sp.Write(buffer, 0, buffer.Length);
                }
                else//16进制发送
                {
                    buffer = StringToHexByte(textBoxSend.Text);
                    sp.Write(buffer, 0, buffer.Length);
                }
                labelSendByte.Text = Convert.ToString(buffer.Length);
            }
            else
            {
                MessageBox.Show("");
            }
        }
        #endregion

        #region 字符串转16进制
        public byte[] StringToHexByte(string str)
        {
            str.Replace(" ", "");
            str.Replace("0x", "");
            str.Replace("0X", "");
            if (str.Length % 2 != 0)
            {
                str = "0" + str;
            }
            byte[] newbuffer = new byte[str.Length / 2];
            for (int i = 0; i < str.Length / 2; i++)
            {
                 newbuffer[i] = Convert.ToByte(str.Substring(i * 2, 2), 16);
            }
            return newbuffer;
        }
        #endregion

        #region 16进制转字符串
        public string HexByteToString(byte[] buffer)
        {
            string str = "";
            if(buffer==null)
            {
                return "0";
            }
            for(int i=0;i<buffer.Length;i++)
            {
                str += buffer[i].ToString("X2");         
            }
            return str;
        }
        #endregion

        #region 清空发送字节
        private void buttonClearSendByte_Click(object sender, EventArgs e)
        {
            labelSendByte.Text = "0";
        }
        #endregion

        #region 清空接收字节
        private void buttonClearRecvByte_Click(object sender, EventArgs e)
        {
            labelReceByte.Text = "0";
        }
        #endregion

        #region 清空发送区
        private void buttonClearSend_Click(object sender, EventArgs e)
        {
            textBoxSend.Text = "";
        }
        #endregion

        #region 清空接收区
        private void buttonClearRecv_Click(object sender, EventArgs e)
        {
            textBoxRec.Text = "";
        }
        #endregion

        //private void ChangeText(byte[] buffer)
        //{
        //    if (radioButtonString.Checked)
        //    {
        //        textBoxRec.Text += Encoding.Default.GetString(buffer);
        //        labelReceByte.Text = buffer.Length.ToString();
        //    }
        //    else
        //    {
        //        textBoxRec.Text += HexByteToString(buffer);
        //        labelReceByte.Text = buffer.Length.ToString();
        //    }
        //}
    }
}

3. 资源下载地址

https://download.csdn.net/download/weixin_38566632/18594094