电气工程师要了解的上位机知识，C#简单几行代码就能实现Modbus通信，源代码分享

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


namespace modbus
{
    public partial class Form1 : Form
    {
        public Form1()
{
            InitializeComponent();
            timer1.Enabled = false;
        }
        //实例化一个串口
        public SerialPort serialPort1 = new SerialPort("COM3");
        IModbusSerialMaster master;
        byte slaveID = 1;
            ushort startAddress = 0;
            ushort numOfPoints = 10;

        private void Form1_Load(object sender, EventArgs e)
{
           

        }

        private void OpenBtn_Click(object sender, EventArgs e)
{
            if (serialPort1.IsOpen == true)
            {
                OpenBtn.Text = "打开串口";
                serialPort1.Close();
                timer1.Enabled = false;
              }

            else {
                timer1.Enabled = true;
                OpenBtn.Text = "关闭串口";
                serialPort1.Open();
               
                //myThread.Start();
            }
            serialPort1.BaudRate = 9600;//配置
            serialPort1.DataBits = 8;//数据位
            serialPort1.Parity = Parity.None;//校验位
            serialPort1.StopBits = StopBits.One;//停止位
            //创建 Rtu 传输模式、通过串口 port 通信的主站
            master = ModbusSerialMaster.CreateRtu(serialPort1);
            master.Transport.ReadTimeout = 1000;//读取串口数据超时为 1000ms master.Transport.WriteTimeout = 1000;//写入串口数据超时
            master.Transport.Retries = 3;//重试次数
        }
       

        private void Form1_FormClosing(object sender, FormClosingEventArgs e)
{
            serialPort1.Close();
            timer1.Enabled = false;
        }

        private void timer1_Tick(object sender, EventArgs e)
{
            bool[] all = master.ReadCoils(slaveID, startAddress, numOfPoints);
            textBox1.Text = all[0].ToString();
            if (all[0] == true)
            {
                button1.BackColor = Color.Red;
            }
            else { button1.BackColor = Color.Green; }

        }

    }
}