C++Modbus通讯

Posted 2020-07-29 Taily老段

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两个VC++ Modbus通信例子源代码.rar

modbus 协议编程 C++

MODBUS_SERVER.h

//Download by http://www.NewXing.com
#if !defined(MSERVERH)
#define MSERVERH
 
#ifdef __cplusplus
extern "C"
{
#endif
    /*1.对单个PLC操作*/
    /*读一个或多个模拟量  参数：站号，开始地址， 读的数量， 返回数据变量指针  返回：－1表示CRC校验失败，－2表示无应答， 大于零表示接收数据成功*/
    char MODBUS_S_ReadMultiRegD(unsigned char rtu, unsigned short int RegAdd, unsigned short int RegCount, short int *list);    
    /*读一个或多个开关量  参数：站号，开始地址， 读的数量， 返回数据变量指针  返回：－1表示CRC校验失败，－2表示无应答， 大于零表示接收数据成功*/
    char MODBUS_S_ReadMultiRegM(unsigned char rtu, unsigned short int RegAdd, unsigned short int RegCount, bool *list);
    /*读一个或多个开关量  参数：站号，开始地址， 读的数量， 返回数据变量指针  返回：－1表示CRC校验失败，－2表示无应答， 大于零表示接收数据成功*/
    char MODBUS_S_ReadMultiRegM_1x(unsigned char rtu, unsigned short int RegAdd, unsigned short int RegCount, bool *list);
    /*写一个模拟量 参数：站号，写地址， 返回数据变量指针  返回：小于零失败，大于零表示成功*/
    char MODBUS_S_WriteSingRegD(unsigned char rtu, unsigned short int RegAdd, short int var);
    /*写一个模拟量 参数：站号，写地址， 返回数据变量指针  返回：小于零失败，大于零表示成功*/
    char MODBUS_S_WriteSingRegM(unsigned char rtu, unsigned short int RegAdd, bool var);
 
    /*2.对全部PLC操作*/
    char MODBUS_S_A_WriteSingRegD(unsigned short int RegAdd, bool var);
    char MODBUS_S_A_WriteSingRegM(unsigned short int RegAdd, short int var);
     
    /*3.端口操作*/
    char MODBUS_S_Init(unsigned long xPort, unsigned long xBabd, unsigned char xDataSize, 
                unsigned char xParity, unsigned char xStopBit);
    char MODBUS_S_UnInit();
     
#ifdef __cplusplus
}
#endif
 
 
#endif

MODBUS_SERVER.cpp

#include "stdafx.h"
#include<stdlib.h>
#include<stdio.h>
#include<string.h>
#include "MODBUS_SHARE.h"
#include "MODBUS_SERVER.h"
#include "PORT.h"
//Download by http://www.NewXing.com
unsigned char buff[256];
 

/*1.对单个PLC操作*/
/*读一个或多个模拟量  参数：站号，开始地址， 读的数量， 返回数据变量指针  返回：－1表示CRC校验失败，－2表示无应答， 大于零表示接收数据成功*/
/*40000*/
char MODBUS_S_ReadMultiRegD(unsigned char rtu, unsigned short int RegAdd, unsigned short int RegCount, short int *list)
{
    unsigned short int crc16;
    unsigned short int crctmp;
    short int vartmp;
     
    memset(buff, 0x00, 255);
    buff[0]= rtu;
    buff[1]= 0x03;
    buff[2]= (unsigned char)((RegAdd-40001) >> 8);
    buff[3]= (unsigned char)(RegAdd-40001);
    buff[4]= (unsigned char)(RegCount >> 8);
    buff[5]= (unsigned char)RegCount;
    crc16= CalcCrcFast(buff, 6);
    buff[6]= (unsigned char)(crc16 >> 8);
    buff[7]= (unsigned char)crc16;
     
    //发送数据
    unsigned long strlen;
    if(IsOpen())
    {
        //发送数据
        strlen= WriteChar(8, (char *)buff);
        if(strlen==8)
        {
            //读数据
            memset(buff, 0x00, 255);
            Sleep(50);
            strlen= ReadChar(255, (char *)buff, 1000);
            if(strlen==0)
            {
                //无返回
                return(-2);             
            }
            else
            {
                //返回长度有效,解析接收缓冲区
                if(strlen== (3+(RegCount *2)+ 2) && buff[0]== rtu && buff[1]== 0x03)
                {
                    crc16= CalcCrcFast(buff, 3+(RegCount*2));
                    crctmp= buff[strlen-2];
                    crctmp= crctmp << 8 | buff[strlen-1];
                    if(crc16== crctmp )
                    {
                        for(int i=0; i< RegCount; i++)
                        {
                            vartmp= buff[3+(2*i)];
                            vartmp= vartmp << 8;
                            vartmp= vartmp | buff[3+((2*i)+1)];
                             
                            list[i]= vartmp;
                        }                               
                    }
                    else
                    {
                        return(-1);
                    }
                }
                else
                {
                    return(-1);
                }
            }
        }
        else
        {           
            return(-2);
        }       
    }
    else
    {
        return(-2);
    }
     
    return(1);
}
 
/*读一个或多个开关量  参数：站号，开始地址， 读的数量， 返回数据变量指针  返回：－1表示CRC校验失败，－2表示无应答， 大于零表示接收数据成功*/
/*00000*/
char MODBUS_S_ReadMultiRegM(unsigned char rtu, unsigned short int RegAdd, unsigned short int RegCount, bool *list)
{
    unsigned short int crc16;
    unsigned short int crctmp;
     
    memset(buff, 0x00, 255);
    buff[0]= rtu;
    buff[1]= 0x01;
    buff[2]= (unsigned char)(RegAdd >> 8);
    buff[3]= (unsigned char)RegAdd;
    buff[4]= (unsigned char)(RegCount >> 8);
    buff[5]= (unsigned char)RegCount;
    crc16= CalcCrcFast(buff, 6);
    buff[6]= (unsigned char)(crc16 >> 8);
    buff[7]= (unsigned char)crc16;
     
    //发送数据
    unsigned long strlen;
    if(IsOpen())
    {
        //发送数据
        strlen= WriteChar(8, (char *)buff);
        if(strlen==8)
        {
            //读数据
            memset(buff, 0x00, 255);
            Sleep(50);
            strlen= ReadChar(255, (char *)buff, 1000);
            if(strlen==0)
            {
                //无返回
                return(-2);             
            }
            else
            {
                //返回长度有效,解析接收缓冲区
                if(strlen== (3+((RegCount+7)/8)+ 2) && buff[0]== rtu && buff[1]== 0x01)
                {
                    crc16= CalcCrcFast(buff, 3+((RegCount +7)/8));
                    crctmp= buff[strlen-2];
                    crctmp= crctmp << 8 | buff[strlen-1];
                    if(crc16== crctmp )
                    {
                        unsigned char row=0, col=0;                     
                        for(int i=0; i<RegCount; i++)
                        {                       
                            row= i / 8;                         
                            col= i % 8;                         
                            list[i]= buff[3 + row] >> col & 0x01;
                        }                               
                    }
                    else
                    {
                        return(-1);
                    }
                }
                else
                {
                    return(-1);
                }
            }
        }
        else
        {           
            return(-2);
        }       
    }
    else
    {
        return(-2);
    }
     
    return(1);
}
 
/*读一个或多个开关量  参数：站号，开始地址， 读的数量， 返回数据变量指针  返回：－1表示CRC校验失败，－2表示无应答， 大于零表示接收数据成功*/
/*10000*/
char MODBUS_S_ReadMultiRegM_1x(unsigned char rtu, unsigned short int RegAdd, unsigned short int RegCount, bool *list)
{
    unsigned short int crc16;
    unsigned short int crctmp;
     
    memset(buff, 0x00, 255);
    buff[0]= rtu;
    buff[1]= 0x02;
    buff[2]= (unsigned char)((RegAdd-10001)>> 8);
    buff[3]= (unsigned char)(RegAdd-10001);
    buff[4]= (unsigned char)(RegCount >> 8);
    buff[5]= (unsigned char)RegCount;
    crc16= CalcCrcFast(buff, 6);
    buff[6]= (unsigned char)(crc16 >> 8);
    buff[7]= (unsigned char)crc16;
     
    //发送数据
    unsigned long strlen;
    if(IsOpen())
    {
        //发送数据
        strlen= WriteChar(8, (char *)buff);
        if(strlen==8)
        {
            //读数据
            memset(buff, 0x00, 255);
            Sleep(50);
            strlen= ReadChar(255, (char *)buff, 1000);
            if(strlen==0)
            {
                //无返回
                return(-2);             
            }
            else
            {
                //返回长度有效,解析接收缓冲区
                if(strlen== (3+((RegCount+7)/8)+ 2) && buff[0]== rtu && buff[1]== 0x02)
                {
                    crc16= CalcCrcFast(buff, 3+((RegCount +7)/8));
                    crctmp= buff[strlen-2];
                    crctmp= crctmp << 8 | buff[strlen-1];
                    if(crc16== crctmp )
                    {
                        unsigned char row=0, col=0;                     
                        for(int i=0; i<RegCount; i++)
                        {                       
                            row= i / 8;                         
                            col= i % 8;                         
                            list[i]= buff[3 + row] >> col & 0x01;
                        }                               
                    }
                    else
                    {
                        return(-1);
                    }
                }
                else
                {
                    return(-1);
                }
            }
        }
        else
        {           
            return(-2);
        }       
    }
    else
    {
        return(-2);
    }
     
    return(1);
}
 
/*写一个模拟量 参数：站号，写地址， 返回数据变量指针  返回：小于零失败，大于零表示成功*/
/*40000*/
char MODBUS_S_WriteSingRegD(unsigned char rtu, unsigned short int RegAdd, short int var)
{
    unsigned short int crc16;
     
    memset(buff, 0x00, 255);
    buff[0]= rtu;
    buff[1]= 0x06;
    buff[2]= (unsigned char)((RegAdd-40001) >> 8);
    buff[3]= (unsigned char)(RegAdd-40001);
    buff[4]= (unsigned char)(var >> 8);
    buff[5]= (unsigned char)var;
    crc16= CalcCrcFast(buff, 6);
    buff[6]= (unsigned char)(crc16 >> 8);
    buff[7]= (unsigned char)crc16;
 
    //发送数据
    unsigned long strlen;
    if(IsOpen())
    {
        //发送数据
        strlen= WriteChar(8, (char *)buff);
        if(strlen==8)
        {
            Sleep(50);
            strlen= ReadChar(255, (char *)buff, 1000);
            //返回长度有效,解析接收缓冲区
            if(!(strlen== 8 && buff[0]== rtu && buff[1]== 0x06))
            {
                return(-1);
            }
        }
        else
        {           
            return(-1);
        }       
    }
    else
    {
        return(-1);
    }
     
    return(1);      
}
 
/*写一个模拟量 参数：站号，写地址， 返回数据变量指针  返回：小于零失败，大于零表示成功*/
char MODBUS_S_WriteSingRegM(unsigned char rtu, unsigned short int RegAdd, bool var)
{
    unsigned short int crc16;
     
    memset(buff, 0x00, 255);
    buff[0]= rtu;
    buff[1]= 0x05;
    buff[2]= (unsigned char)(RegAdd >> 8);
    buff[3]= (unsigned char)RegAdd;
    if(var)
    {
        buff[4]= 0xff;
        buff[5]= 0x00;
    }
    else
    {
        buff[4]= 0x00;
        buff[5]= 0x00;
    }
    crc16= CalcCrcFast(buff, 6);
    buff[6]= (unsigned char)(crc16 >> 8);
    buff[7]= (unsigned char)crc16;
     
    //发送数据
    unsigned long strlen;
    if(IsOpen())
    {
        //发送数据
        Sleep(50);
        strlen= WriteChar(8, (char *)buff);
        if(strlen==8)
        {
            Sleep(50);
            strlen= ReadChar(255, (char *)buff, 1000);
            //返回长度有效,解析接收缓冲区
            if(!(strlen== 8 && buff[0]== rtu && buff[1]== 0x05))
            {
                return(-1);
            }
        }
        else
        {           
            return(-1);
        }       
    }
    else
    {
        return(-1);
    }
     
    return(1);  
}
 
//
/*2.对全部PLC操作*/
char MODBUS_S_A_WriteSingRegD(unsigned short int RegAdd, short int var)
{
    unsigned short int crc16;
     
    memset(buff, 0x00, 255);
    buff[0]= 0xff;
    buff[1]= 0x06;
    buff[2]= (unsigned char)((RegAdd -40001) >> 8);
    buff[3]= (unsigned char)(RegAdd -40001);
    buff[4]= (unsigned char)(var >> 8);
    buff[5]= (unsigned char)var;
    crc16= CalcCrcFast(buff, 6);
    buff[6]= (unsigned char)(crc16 >> 8);
    buff[7]= (unsigned char)crc16;
 
    //发送数据
    unsigned long strlen;
    if(IsOpen())
    {
        //发送数据
        strlen= WriteChar(8, (char *)buff);
        if(strlen!=8)
        {           
            return(-1);
        }       
    }
    else
    {
        return(-1);
    }
     
    return(1);  
}
 
char MODBUS_S_A_WriteSingRegM(unsigned short int RegAdd, bool var)
{
    unsigned short int crc16;
     
    memset(buff, 0x00, 255);
    buff[0]= 0xff;
    buff[1]= 0x05;
    buff[2]= (unsigned char)(RegAdd >> 8);
    buff[3]= (unsigned char)RegAdd;
    if(var)
    {
        buff[4]= 0xff;
        buff[5]= 0x00;
    }
    else
    {
        buff[4]= 0x00;
        buff[5]= 0x00;
    }
    crc16= CalcCrcFast(buff, 6);
    buff[6]= (unsigned char)(crc16 >> 8);
    buff[7]= (unsigned char)crc16;
     
    //发送数据
    unsigned long strlen;
    if(IsOpen())
    {
        //发送数据
        strlen= WriteChar(8, (char *)buff);
        if(strlen!=8)
        {           
            return(-1);
        }       
    }
    else
    {
        return(-1);
    }
     
    return(1);  
}
 

char MODBUS_S_Init(unsigned long xPort, unsigned long xBabd, unsigned char xDataSize, 
                unsigned char xParity, unsigned char xStopBit)
{
    /*
    Parity :
    EVENPARITY Even 
    MARKPARITY Mark 
    NOPARITY No parity 
    ODDPARITY Odd 
    SPACEPARITY Space 
    */ 
    /*BaudRate:
    CBR_110
    CBR_19200
    CBR_300
    CBR_38400
    CBR_600
    CBR_56000
    CBR_1200
    CBR_57600
    CBR_2400
    CBR_115200
    CBR_4800
    CBR_128000
    CBR_9600
    CBR_256000
    CBR_14400   
    */
    /*
    ONESTOPBIT 1 stop bit 
    ONE5STOPBITS 1.5 stop bits 
    TWOSTOPBITS 
    */
 
    if(OpenPort(xPort,xBabd,xDataSize,xParity, xStopBit,4096,4096,1000))
    {
        return(1);
    }
    else
    {
        return(0);
    }
}
 
char MODBUS_S_UnInit()
{
    ClosePort();
    return(1);
}

MODBUS_SHARE.h

//Download by http://www.NewXing.com
#if !defined(MSHAREH)
#define MSHAREH
 
#ifdef __cplusplus
extern "C"
{
    #endif
     
    unsigned short CalcCrcFast(unsigned char*puchMsg,unsigned short usDataLen);
     
    #ifdef __cplusplus
}
#endif
 
#endif

MODBUS_SHARE.cpp

#include "stdafx.h"
#include "MODBUS_SHARE.h"
//Download by http://www.NewXing.com
const unsigned char m_auchCRCHi[]=
{
    0x00,0xC1,0x81,0x40,0x01,0xC0,0x80,0x41,0x01,0xC0,
    0x80,0x41,0x00,0xC1,0x81,0x40,0x01,0xC0,0x80,0x41,
    0x00,0xC1,0x81,0x40,0x00,0xC1,0x81,0x40,0x01,0xC0,
    0x80,0x41,0x01,0xC0,0x80,0x41,0x00,0xC1,0x81,0x40,
    0x00,0xC1,0x81,0x40,0x01,0xC0,0x80,0x41,0x00,0xC1,
    0x81,0x40,0x01,0xC0,0x80,0x41,0x01,0xC0,0x80,0x41,
    0x00,0xC1,0x81,0x40,0x01,0xC0,0x80,0x41,0x00,0xC1,
    0x81,0x40,0x00,0xC1,0x81,0x40,0x01,0xC0,0x80,0x41,
    0x00,0xC1,0x81,0x40,0x01,0xC0,0x80,0x41,0x01,0xC0,
    0x80,0x41,0x00,0xC1,0x81,0x40,0x00,0xC1,0x81,0x40,
    0x01,0xC0,0x80,0x41,0x01,0xC0,0x80,0x41,0x00,0xC1,
    0x81,0x40,0x01,0xC0,0x80,0x41,0x00,0xC1,0x81,0x40,
    0x00,0xC1,0x81,0x40,0x01,0xC0,0x80,0x41,0x01,0xC0,
    0x80,0x41,0x00,0xC1,0x81,0x40,0x00,0xC1,0x81,0x40,
    0x01,0xC0,0x80,0x41,0x00,0xC1,0x81,0x40,0x01,0xC0,
    0x80,0x41,0x01,0xC0,0x80,0x41,0x00,0xC1,0x81,0x40,
    0x00,0xC1,0x81,0x40,0x01,0xC0,0x80,0x41,0x01,0xC0,
    0x80,0x41,0x00,0xC1,0x81,0x40,0x01,0xC0,0x80,0x41,
    0x00,0xC1,0x81,0x40,0x00,0xC1,0x81,0x40,0x01,0xC0,
    0x80,0x41,0x00,0xC1,0x81,0x40,0x01,0xC0,0x80,0x41,
    0x01,0xC0,0x80,0x41,0x00,0xC1,0x81,0x40,0x01,0xC0,
    0x80,0x41,0x00,0xC1,0x81,0x40,0x00,0xC1,0x81,0x40,
    0x01,0xC0,0x80,0x41,0x01,0xC0,0x80,0x41,0x00,0xC1,
    0x81,0x40,0x00,0xC1,0x81,0x40,0x01,0xC0,0x80,0x41,
    0x00,0xC1,0x81,0x40,0x01,0xC0,0x80,0x41,0x01,0xC0,
    0x80,0x41,0x00,0xC1,0x81,0x40 
}
;
 
const unsigned char m_auchCRCLo[]=
{
    0x00,0xC0,0xC1,0x01,0xC3,0x03,0x02,0xC2,0xC6,0x06,
    0x07,0xC7,0x05,0xC5,0xC4,0x04,0xCC,0x0C,0x0D,0xCD,
    0x0F,0xCF,0xCE,0x0E,0x0A,0xCA,0xCB,0x0B,0xC9,0x09,
    0x08,0xC8,0xD8,0x18,0x19,0xD9,0x1B,0xDB,0xDA,0x1A,
    0x1E,0xDE,0xDF,0x1F,0xDD,0x1D,0x1C,0xDC,0x14,0xD4,
    0xD5,0x15,0xD7,0x17,0x16,0xD6,0xD2,0x12,0x13,0xD3,
    0x11,0xD1,0xD0,0x10,0xF0,0x30,0x31,0xF1,0x33,0xF3,
    0xF2,0x32,0x36,0xF6,0xF7,0x37,0xF5,0x35,0x34,0xF4,
    0x3C,0xFC,0xFD,0x3D,0xFF,0x3F,0x3E,0xFE,0xFA,0x3A,
    0x3B,0xFB,0x39,0xF9,0xF8,0x38,0x28,0xE8,0xE9,0x29,
    0xEB,0x2B,0x2A,0xEA,0xEE,0x2E,0x2F,0xEF,0x2D,0xED,
    0xEC,0x2C,0xE4,0x24,0x25,0xE5,0x27,0xE7,0xE6,0x26,
    0x22,0xE2,0xE3,0x23,0xE1,0x21,0x20,0xE0,0xA0,0x60,
    0x61,0xA1,0x63,0xA3,0xA2,0x62,0x66,0xA6,0xA7,0x67,
    0xA5,0x65,0x64,0xA4,0x6C,0xAC,0xAD,0x6D,0xAF,0x6F,
    0x6E,0xAE,0xAA,0x6A,0x6B,0xAB,0x69,0xA9,0xA8,0x68,
    0x78,0xB8,0xB9,0x79,0xBB,0x7B,0x7A,0xBA,0xBE,0x7E,
    0x7F,0xBF,0x7D,0xBD,0xBC,0x7C,0xB4,0x74,0x75,0xB5,
    0x77,0xB7,0xB6,0x76,0x72,0xB2,0xB3,0x73,0xB1,0x71,
    0x70,0xB0,0x50,0x90,0x91,0x51,0x93,0x53,0x52,0x92,
    0x96,0x56,0x57,0x97,0x55,0x95,0x94,0x54,0x9C,0x5C,
    0x5D,0x9D,0x5F,0x9F,0x9E,0x5E,0x5A,0x9A,0x9B,0x5B,
    0x99,0x59,0x58,0x98,0x88,0x48,0x49,0x89,0x4B,0x8B,
    0x8A,0x4A,0x4E,0x8E,0x8F,0x4F,0x8D,0x4D,0x4C,0x8C,
    0x44,0x84,0x85,0x45,0x87,0x47,0x46,0x86,0x82,0x42,
    0x43,0x83,0x41,0x81,0x80,0x40 
}
;
 
unsigned short CalcCrcFast(unsigned char*puchMsg,unsigned short usDataLen)
{
    unsigned char uchCRCHi=0xFF ;
    unsigned char uchCRCLo=0xFF ;
    unsigned short uIndex ;
     
    while(usDataLen--)
    {
        uIndex=uchCRCHi^*puchMsg++;
        uchCRCHi=uchCRCLo^m_auchCRCHi[uIndex];
        uchCRCLo=m_auchCRCLo[uIndex];
    }
    return(uchCRCHi<<8|uchCRCLo);
}

PORT.h

//Download by http://www.NewXing.com
#if !defined(MPORT)
#define MPORT
 
 
#ifdef __cplusplus
extern "C"
{
#endif
 
    inline bool IsOpen();
    bool OpenPort(unsigned long xPort, unsigned long xBabd, unsigned char xDataSize, 
                unsigned char xParity, unsigned char xStopBit, unsigned long InputBuffSize, 
                unsigned long OutputBuffSize, unsigned long dwTimerOut);
    void ClosePort();
    void ClearBuffer();
    unsigned long ReadChar(unsigned long dwBufferLength, char *buff, unsigned long dwWaitTime);
    unsigned long WriteChar(unsigned long dwBufferLength, char *buff);
     
#ifdef __cplusplus
}
#endif
 
#endif

PORT.cpp

//Download by http://www.NewXing.com
#include "stdafx.h"
#include <stdio.h>
#include <stdlib.h>
#include <windows.h>
#include "PORT.h"
 
//
DCB dcb;
COMMTIMEOUTS CommTimerOuts;
HANDLE hCom= INVALID_HANDLE_VALUE;
 
OVERLAPPED m_overlappedRead;
OVERLAPPED m_overlappedWrite;
 
//
//通讯端口是否打开
inline bool IsOpen()
{
    return hCom != INVALID_HANDLE_VALUE;
} 
 
//设置超时
void SetTimerOut(unsigned long dwTimerOut= 5000)
{
    if(!IsOpen())  
    {
        return;   
    }
     
    CommTimerOuts.ReadIntervalTimeout= MAXDWORD;
    CommTimerOuts.ReadTotalTimeoutConstant= 0;
    CommTimerOuts.ReadTotalTimeoutMultiplier= 0;
    CommTimerOuts.WriteTotalTimeoutConstant= dwTimerOut;
    CommTimerOuts.WriteTotalTimeoutMultiplier= 0;
 
    SetCommTimeouts(hCom, &CommTimerOuts);
}
 
//设置DCB参数
bool SetDCBParm(unsigned long xBabd, unsigned char xDataSize, 
                unsigned char xParity, unsigned char xStopBit)
{
    if(!IsOpen())  
    {
        return false;   
    }
     
    if (!GetCommState(hCom, &dcb)) 
    {
        #ifdef _DEBUG
            printf ("错误: %d << 等到通讯口参数失败.\\n", GetLastError());
        #endif
         
        ClosePort();
        return (false);
    }   
    //设置通讯参数    
    dcb.DCBlength= sizeof(DCB); 
    dcb.BaudRate = xBabd;     // set the baud rate
    dcb.ByteSize = xDataSize; // data size, xmit, and rcv
    dcb.Parity =   xParity;   // no parity bit
    dcb.StopBits = xStopBit;  // one stop bit   
    if (!SetCommState(hCom, &dcb)) 
    {
        #ifdef _DEBUG
            printf ("错误: %d << 设置通讯端口参数失败.\\n", GetLastError());
        #endif
        ClosePort();
        return (false);
    }   
 
    return true;
}
 
//设置端口缓冲区大小
bool SetPortBuffSize(unsigned long InputBuffSize, unsigned long OutputBuffSize)
{
    if(!IsOpen())  
    {
        return false;   
    } 
     
    if(!SetupComm(hCom, InputBuffSize, OutputBuffSize))
    {
        #ifdef _DEBUG
            printf ("错误: %d << 设置通讯端口缓冲失败.\\n", GetLastError());
        #endif
        ClosePort();
        return (false);
    }   
 
    return true;
}
 
//清理所有缓冲区
void ClearBuffer()
{
    if(!IsOpen())  
    {
        return;   
    }
 
    PurgeComm(hCom, PURGE_RXCLEAR | PURGE_TXCLEAR | PURGE_RXABORT | PURGE_TXABORT);
}
 
//当前接收缓冲区字节数目; 
unsigned long GetInBuffCount()
{
    if(!IsOpen())  
    {
    return(0);   
    }
 
    DWORD     dwErrorFalgs;
    COMSTAT   Comstat;
 
    ClearCommError(hCom, &dwErrorFalgs, &Comstat);
    return Comstat.cbInQue;
}
 
//当前发送缓冲区字节数目; 
unsigned long GetOutBuffCount()
{
    if(!IsOpen())  
    {
        return false;   
    }
 
    DWORD     dwErrorFalgs;
    COMSTAT   Comstat;
 
    ClearCommError(hCom, &dwErrorFalgs, &Comstat);
    return Comstat.cbOutQue;
}
 
///打开串口 
bool OpenPort(unsigned long xPort, unsigned long xBabd, unsigned char xDataSize, 
                unsigned char xParity, unsigned char xStopBit, unsigned long InputBuffSize,
                unsigned long OutputBuffSize, unsigned long dwTimerOut)
{   
    if(IsOpen())
    {
        ClosePort();
    }   
    //设置事件 
    memset(&m_overlappedRead,0,sizeof(OVERLAPPED));
    m_overlappedRead.hEvent= CreateEvent(NULL,FALSE,TRUE,"portread");
    ASSERT(m_overlappedRead.hEvent != INVALID_HANDLE_VALUE);
 
    memset(&m_overlappedWrite,0,sizeof(OVERLAPPED));   
    m_overlappedWrite.hEvent= CreateEvent(NULL,FALSE,TRUE,"portwrite");  
    ASSERT(m_overlappedWrite.hEvent != INVALID_HANDLE_VALUE);
    //取得串口字符
    char com_str[255];
    strcpy(com_str, "COM");
    ltoa(xPort, com_str + 3, 10);
    //打开通讯端口 
    hCom = CreateFile(com_str,
                    GENERIC_READ | GENERIC_WRITE,
                    0,    
                    NULL, 
                    OPEN_EXISTING, 
                    FILE_ATTRIBUTE_NORMAL | FILE_FLAG_OVERLAPPED,    
                    NULL  
                    );
    if (hCom == INVALID_HANDLE_VALUE) 
    {
        #ifdef _DEBUG
            printf ("错误: %d << 打开通讯口失败,请检查是否已经安装串口设备.\\n", GetLastError());
        #endif
        return (false);
    }     
    SetPortBuffSize(InputBuffSize,OutputBuffSize);
    SetDCBParm(xBabd,xDataSize,xParity,xStopBit);   
    SetTimerOut(dwTimerOut);    
    //清理缓冲器
    PurgeComm(hCom, PURGE_RXCLEAR | PURGE_TXCLEAR | PURGE_RXABORT | PURGE_TXABORT);
    //启动成功
    #ifdef _DEBUG
        printf ("成功开启端口 %d.\\n", com_str);
    #endif
    return(true);
}
 
//关闭串口;
void ClosePort()
{
    if(IsOpen())
    {
        CloseHandle(hCom);      
        hCom= INVALID_HANDLE_VALUE;
    }    
     
    //ResetEvent(m_overlappedRead.hEvent);
    //ResetEvent(m_overlappedWrite.hEvent); 
 
    if(m_overlappedRead.hEvent!=NULL) 
    {
        CloseHandle(m_overlappedRead.hEvent);        
    }
    if(m_overlappedWrite.hEvent!=NULL) 
    {
        CloseHandle(m_overlappedWrite.hEvent);        
    }   
}
 
//异步读数据
unsigned long ReadChar(unsigned long dwBufferLength, char *buff, unsigned long dwWaitTime=20)
{   
    if(!IsOpen())  
    {
        return(0);   
    }
     
    DWORD       dwError;
    COMSTAT     Stat;  
    if(::ClearCommError(hCom, &dwError, &Stat) && dwError > 0)   //清除错误
    {
        ::PurgeComm(hCom, PURGE_RXABORT | PURGE_RXCLEAR); /*清除输入缓冲区*/
        return 0;
    }
    if(!Stat.cbInQue)// 缓冲区无数据
    {
        return 0;
    }
 
    unsigned long uReadLength = 0;
    dwBufferLength = dwBufferLength - 1 > Stat.cbInQue ? Stat.cbInQue : dwBufferLength - 1;
    if(!::ReadFile(hCom, buff, dwBufferLength, &uReadLength, &m_overlappedRead)) //2000 下 ReadFile 始终返回 True
    {
        if(::GetLastError() == ERROR_IO_PENDING) // 结束异步I/O
        {
            WaitForSingleObject(m_overlappedRead.hEvent, dwWaitTime);   //等待20ms
            if(!::GetOverlappedResult(hCom, &m_overlappedRead, &uReadLength, false))
            {
                if(::GetLastError() != ERROR_IO_INCOMPLETE)//其他错误
                {
                    uReadLength = 0;
                }
            }
        }
        else
        {
            uReadLength = 0;
        }
    }
         
    return uReadLength;
}
 
//异步写数据 
unsigned long WriteChar(unsigned long dwBufferLength, char *buff)
{
    if(!IsOpen())
    {
        return 0;
    }
 
    DWORD dwError;
    if(ClearCommError(hCom, &dwError, NULL) && dwError > 0)  //清除错误
    {
        PurgeComm(hCom, PURGE_TXABORT | PURGE_TXCLEAR); 
    }
 
    unsigned long uWriteLength = 0;
    if(!WriteFile(hCom, buff, dwBufferLength, &uWriteLength, &m_overlappedWrite))
    {
        if(GetLastError() == ERROR_IO_PENDING)
        {
            DWORD m_tmp=0;
            m_tmp= WaitForSingleObject(m_overlappedWrite.hEvent, 1000);
            if(m_tmp== WAIT_TIMEOUT || m_tmp== WAIT_ABANDONED)
            {
                return(0);
            }
            else if(m_tmp== WAIT_OBJECT_0)
            {           
                if(!GetOverlappedResult(hCom,&m_overlappedWrite,&uWriteLength,false))
                {
                    return(0);      
                }
                else
                {
                    return uWriteLength;        
                }
            }
             
            uWriteLength = 0;
        }
    }
 
    return uWriteLength;  
}

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