TrainCamp_zhangyongpan_Modbus/ModbusDemo/Device/ModbusRTU.cs

using ModbusDemo.Uitls;
using System;
using System.Collections.Generic;
using System.IO.Ports;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;

namespace ModbusDemo.Device
{
    public class ModbusRTU : IModbusRTU
    {
        private SerialPort _serialPort;

        public ModbusRTU(SerialPort serialPort)
        {
            _serialPort = serialPort;
        }
        /// <summary>
        /// 用来发送读写线圈的指令
        /// </summary>
        /// <param name="slaveAddress"></param>
        /// <param name="startAddress"></param>
        /// <param name="numberOfPoints"></param>
        /// <returns></returns>
        public bool[] ReadCoil(byte slaveAddress, ushort startAddress, ushort numberOfPoints)
        {

            List<byte> sendByteList = new List<byte>();
            //设置从站地址
            sendByteList.Add(slaveAddress);
            //设置功能码
            sendByteList.Add(0x01);
            //设置起始地址的高位和低位
            sendByteList.Add(BitConverter.GetBytes(startAddress)[1]);
            sendByteList.Add(BitConverter.GetBytes(startAddress)[0]);
            //设置读取几个线圈的高位和低位
            sendByteList.Add(BitConverter.GetBytes(numberOfPoints)[1]);
            sendByteList.Add(BitConverter.GetBytes(numberOfPoints)[0]);
            //获取CRC校验码
            byte[] getCRC = sendByteList.ToArray();
            byte[] resultCRC = CRCUitl.CalculateCRC(getCRC, getCRC.Length);
            sendByteList.Add(resultCRC[0]);
            sendByteList.Add(resultCRC[1]);

            byte[] sendByte = sendByteList.ToArray();
            if (_serialPort.IsOpen)
            {
                // 清空接收缓冲区（避免残留数据干扰）
                _serialPort.DiscardInBuffer();

                _serialPort.Write(sendByte, 0, sendByte.Length);
                Thread.Sleep(300);
                byte[] response = new byte[_serialPort.BytesToRead];
                _serialPort.Read(response, 0, _serialPort.BytesToRead);
                return Parseresponse(response,numberOfPoints);
            }


            return null;
        }


        public bool[] Parseresponse(byte[] response, ushort numberOfPoints)
        {
            //判断发送回来的数据是否正确
            CheckData.CheckResponse(response);

            if (!CRCUitl.ValidateCRC(response))
            {
                MessageBox.Show("0x14:CRC校验错误");
                return null;
            }
            List<byte> responseList = new List<byte>(response);
            //移除前两位
            responseList.RemoveRange(0, 3);
            //移除后两位校验码
            responseList.RemoveRange(responseList.Count - 2, 2);
            responseList.Reverse();
            //数组反转之后，转为二进制字符
            List<string> StringList = responseList.Select(m => Convert.ToString(m, 2)).ToList();

            var result = "";

            foreach (var item in StringList)
            {
                result += item.PadLeft(8, '0');
            }
            //先将字符串转为数组，再反转，再转为字节数组
            char[] chars = result.ToArray().Reverse<char>().ToArray();
            bool[] f = new bool[numberOfPoints];
            for (int i = 0; i < numberOfPoints; i++)
            {
                if (chars[i] == '1')
                {
                    f[i] = true;
                }
                else
                {
                    f[i] = false;
                }
            }
            return f;
        }

    }
}