C++Modbus通讯
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两个VC++ Modbus通信例子源代码.rar
//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
#endifMODBUS_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
#endifMODBUS_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
#endifPORT.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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