serial.cs

基于C#的串口通讯管理类,含有CRC校验.

using System;
using System.Runtime.InteropServices;

namespace BusApp
{
    /// <summary>
    /// 
    /// </summary>
    public class mycom
    {
        public mycom()
        {
            // 
            // TODO: 在此处添加构造函数逻辑
            //
        }
        public int PortNum; //1,2,3,4
        public int BaudRate; //1200,2400,4800,9600
        public byte ByteSize; //8 bits
        public byte Parity; // 0-4=no,odd,even,mark,space 
        public byte StopBits; // 0,1,2 = 1, 1.5, 2 
        public int ReadTimeout; //10

        //comm port win32 file handle
        private int hComm = -1;

        public bool Opened = false;

        //win32 api constants
        private const uint GENERIC_READ = 0x80000000;
        private const uint GENERIC_WRITE = 0x40000000;
        private const int OPEN_EXISTING = 3;
        private const int INVALID_HANDLE_VALUE = -1;

        [StructLayout(LayoutKind.Sequential)]
        private struct DCB
        {
            //taken from c struct in platform sdk 
            public int DCBlength;           // sizeof(DCB) 
            public int BaudRate;            // current baud rate 
            public int fBinary;          // binary mode, no EOF check 
            public int fParity;          // enable parity checking 
            public int fOutxCtsFlow;      // CTS output flow control 
            public int fOutxDsrFlow;      // DSR output flow control 
            public int fDtrControl;       // DTR flow control type 
            public int fDsrSensitivity;   // DSR sensitivity 
            public int fTXContinueOnXoff; // XOFF continues Tx 
            public int fOutX;          // XON/XOFF out flow control 
            public int fInX;           // XON/XOFF in flow control 
            public int fErrorChar;     // enable error replacement 
            public int fNull;          // enable null stripping 
            public int fRtsControl;     // RTS flow control 
            public int fAbortOnError;   // abort on error 
            public int fDummy2;        // reserved 
            public ushort wReserved;          // not currently used 
            public ushort XonLim;             // transmit XON threshold 
            public ushort XoffLim;            // transmit XOFF threshold 
            public byte ByteSize;           // number of bits/byte, 4-8 
            public byte Parity;             // 0-4=no,odd,even,mark,space 
            public byte StopBits;           // 0,1,2 = 1, 1.5, 2 
            public char XonChar;            // Tx and Rx XON character 
            public char XoffChar;           // Tx and Rx XOFF character 
            public char ErrorChar;          // error replacement character 
            public char EofChar;            // end of input character 
            public char EvtChar;            // received event character 
            public ushort wReserved1;         // reserved; do not use 
        }

        [StructLayout(LayoutKind.Sequential)]
        private struct COMMTIMEOUTS
        {
            public int ReadIntervalTimeout;
            public int ReadTotalTimeoutMultiplier;
            public int ReadTotalTimeoutConstant;
            public int WriteTotalTimeoutMultiplier;
            public int WriteTotalTimeoutConstant;
        }

        [StructLayout(LayoutKind.Sequential)]
        private struct OVERLAPPED
        {
            public int Internal;
            public int InternalHigh;
            public int Offset;
            public int OffsetHigh;
            public int hEvent;
        }

        [DllImport("kernel32.dll")]
        private static extern int CreateFile(
         string lpFileName,                         // file name
         uint dwDesiredAccess,                      // access mode
         int dwShareMode,                          // share mode
         int lpSecurityAttributes, // SD
         int dwCreationDisposition,                // how to create
         int dwFlagsAndAttributes,                 // file attributes
         int hTemplateFile                        // handle to template file
         );
        [DllImport("kernel32.dll")]
        private static extern bool GetCommState(
         int hFile,  // handle to communications device
         ref DCB lpDCB    // device-control block
         );
        [DllImport("kernel32.dll")]
        private static extern bool BuildCommDCB(
         string lpDef,  // device-control string
         ref DCB lpDCB     // device-control block
         );
        [DllImport("kernel32.dll")]
        private static extern bool SetCommState(
         int hFile,  // handle to communications device
         ref DCB lpDCB    // device-control block
         );
        [DllImport("kernel32.dll")]
        private static extern bool GetCommTimeouts(
         int hFile,                  // handle to comm device
         ref COMMTIMEOUTS lpCommTimeouts  // time-out values
         );
        [DllImport("kernel32.dll")]
        private static extern bool SetCommTimeouts(
         int hFile,                  // handle to comm device
         ref COMMTIMEOUTS lpCommTimeouts  // time-out values
         );
        [DllImport("kernel32.dll")]
        private static extern bool ReadFile(
         int hFile,                // handle to file
         byte[] lpBuffer,             // data buffer
         int nNumberOfBytesToRead,  // number of bytes to read
         ref int lpNumberOfBytesRead, // number of bytes read
         ref OVERLAPPED lpOverlapped    // overlapped buffer
         );
        [DllImport("kernel32.dll")]
        private static extern bool WriteFile(
         int hFile,                    // handle to file
         byte[] lpBuffer,                // data buffer
         int nNumberOfBytesToWrite,     // number of bytes to write
         ref int lpNumberOfBytesWritten,  // number of bytes written
         ref OVERLAPPED lpOverlapped        // overlapped buffer
         );
        [DllImport("kernel32.dll")]
        private static extern bool CloseHandle(
         int hObject   // handle to object
         );

        public void Open()
        {

            DCB dcbCommPort = new DCB();
            COMMTIMEOUTS ctoCommPort = new COMMTIMEOUTS();


            // OPEN THE COMM PORT.


            hComm = CreateFile("COM" + PortNum, GENERIC_READ | GENERIC_WRITE, 0, 0, OPEN_EXISTING, 0, 0);

            // IF THE PORT CANNOT BE OPENED, BAIL OUT.
            if (hComm == INVALID_HANDLE_VALUE)
            {
                throw (new ApplicationException("Comm Port Can Not Be Opened"));
            }

            // SET THE COMM TIMEOUTS.

            GetCommTimeouts(hComm, ref ctoCommPort);
            ctoCommPort.ReadTotalTimeoutConstant = ReadTimeout;
            ctoCommPort.ReadTotalTimeoutMultiplier = 0;
            ctoCommPort.WriteTotalTimeoutMultiplier = 0;
            ctoCommPort.WriteTotalTimeoutConstant = 0;
            SetCommTimeouts(hComm, ref ctoCommPort);

            // SET BAUD RATE, PARITY, WORD SIZE, AND STOP BITS.
            // THERE ARE OTHER WAYS OF DOING SETTING THESE BUT THIS IS THE EASIEST.
            // IF YOU WANT TO LATER ADD CODE FOR OTHER BAUD RATES, REMEMBER
            // THAT THE ARGUMENT FOR BuildCommDCB MUST BE A POINTER TO A STRING.
            // ALSO NOTE THAT BuildCommDCB() DEFAULTS TO NO HANDSHAKING.

            dcbCommPort.DCBlength = Marshal.SizeOf(dcbCommPort);
            GetCommState(hComm, ref dcbCommPort);
            dcbCommPort.BaudRate = BaudRate;
            dcbCommPort.Parity = Parity;
            dcbCommPort.ByteSize = ByteSize;
            dcbCommPort.StopBits = StopBits;
            SetCommState(hComm, ref dcbCommPort);

            Opened = true;

        }

        public void Close()
        {
            if (hComm != INVALID_HANDLE_VALUE)
            {
                CloseHandle(hComm);
                Opened = false;
            }
        }

        public byte[] Read(int NumBytes)
        {
            byte[] BufBytes;
            byte[] OutBytes;
            BufBytes = new byte[NumBytes];
            if (hComm != INVALID_HANDLE_VALUE)
            {
                OVERLAPPED ovlCommPort = new OVERLAPPED();
                int BytesRead = 0;
                ReadFile(hComm, BufBytes, NumBytes, ref BytesRead, ref ovlCommPort);
                OutBytes = new byte[BytesRead];
                Array.Copy(BufBytes, OutBytes, BytesRead);
            }
            else
            {
                throw (new ApplicationException("Comm Port Not Open"));
            }
            return OutBytes;
        }

        public int Write(byte[] WriteBytes)
        {
            int BytesWritten = 0;
            if (hComm != INVALID_HANDLE_VALUE)
            {
                OVERLAPPED ovlCommPort = new OVERLAPPED();
                WriteFile(hComm, WriteBytes, WriteBytes.Length, ref BytesWritten, ref ovlCommPort);
            }
            else
            {
                throw (new ApplicationException("Comm Port Not Open"));
            }
            return BytesWritten;
        }
    }

    /// <summary>
    /// 消息CRC校验算法
    /// </summary>
    public class CRC
    {
        //private int key = 0x11021H;
        public CRC()
        {

        }
        public static int GetKey(byte[] data)
        {
            int count = data.Length;
            byte[] buf = new byte[data.Length + 2];
            data.CopyTo(buf, 0);
            int ptr = 0;
            int i = 0;
            int crc = 0;
            byte crc1, crc2, crc3;
            crc1 = buf[ptr++];
            crc2 = buf[ptr++];
            buf[count] = 0;
            buf[count + 1] = 0;
            while (--count >= 0)
            {
                crc3 = buf[ptr++];
                for (i = 0; i < 8; i++)
                {
                    if (((crc1 & 0x80) >> 7) == 1)//判断crc1高位是否为1
                    {
                        crc1 = (byte)(crc1 << 1); //移出高位
                        if (((crc2 & 0x80) >> 7) == 1)//判断crc2高位是否为1
                        {
                            crc1 = (byte)(crc1 | 0x01);//crc1低位由0变1
                        }
                        crc2 = (byte)(crc2 << 1);//crc2移出高位
                        if (((crc3 & 0x80) >> 7) == 1) //判断crc3高位是否为1
                        {
                            crc2 = (byte)(crc2 | 0x01); //crc2低位由0变1
                        }
                        crc3 = (byte)(crc3 << 1);//crc3移出高位
                        crc1 = (byte)(crc1 ^ 0x10);
                        crc2 = (byte)(crc2 ^ 0x21);
                    }
                    else
                    {
                        crc1 = (byte)(crc1 << 1); //移出高位
                        if (((crc2 & 0x80) >> 7) == 1)//判断crc2高位是否为1
                        {
                            crc1 = (byte)(crc1 | 0x01);//crc1低位由0变1
                        }
                        crc2 = (byte)(crc2 << 1);//crc2移出高位
                        if (((crc3 & 0x80) >> 7) == 1) //判断crc3高位是否为1
                        {
                            crc2 = (byte)(crc2 | 0x01); //crc2低位由0变1
                        }
                        crc3 = (byte)(crc3 << 1);//crc3移出高位
                    }
                }
            }
            crc = (int)((crc1 << 8) + crc2);
            return crc;
        }
    }
}