c++编写的串口通讯程序

#include "stdafx.h" #include <iostream> #include "com.h" #include <process.h> My_Com::My_Com() : hCom(INVALID_HANDLE_VALUE), m_IsOpen(false), m_Thread(NULL) { //void *memset(void *s, int ch, size_t n);将s中当前位置后面的n个字节用ch替换并返回s memset(&m_ovWait, 0, sizeof(m_ovWait)); memset(&m_ovWrite, 0, sizeof(m_ovWrite)); memset(&m_ovRead, 0, sizeof(m_ovRead)); } My_Com::~My_Com() { Close_Com(); } bool My_Com::Open_Com(LPCWSTR Port) { hCom = CreateFile( Port, //将要打开的串口逻辑名 GENERIC_READ | GENERIC_WRITE, //允许读和写 0, //指定共享属性，由于串口不能共享，该参数必须置为0,独占方式 NULL,//引用安全性属性结构，缺省值为NULL OPEN_EXISTING, //打开而不是创建 FILE_ATTRIBUTE_NORMAL | FILE_FLAG_OVERLAPPED, //重叠方式 NULL //对串口而言该参数必须置为NULL ); if (hCom == INVALID_HANDLE_VALUE) { printf ("打开串口失败!\n"); return FALSE; } else { printf("打开串口成功！\n"); } return TRUE; } bool My_Com::Config_Com() { SetupComm(hCom, 1024, 1024); //输入缓冲区和输出缓冲区的大小都是1024 COMMTIMEOUTS TimeOuts; //设定读超时 TimeOuts.ReadIntervalTimeout = MAXDWORD; TimeOuts.ReadTotalTimeoutMultiplier = 0; TimeOuts.ReadTotalTimeoutConstant = 0; //设定写超时 TimeOuts.WriteTotalTimeoutMultiplier = 500; TimeOuts.WriteTotalTimeoutConstant = 2000; SetCommTimeouts(hCom, &TimeOuts); //设置超时 DCB dcb; GetCommState(hCom, &dcb); dcb.BaudRate = 9600; //波特率为9600 dcb.ByteSize = 8; //每个字节有8位 dcb.Parity = NOPARITY; //无奇偶校验位 dcb.StopBits = TWOSTOPBITS; //两个停止位 SetCommState(hCom, &dcb); PurgeComm(hCom, PURGE_TXCLEAR | PURGE_RXCLEAR); m_ovRead.hEvent = CreateEvent(NULL, false, false, NULL); m_ovWrite.hEvent = CreateEvent(NULL, false, false, NULL); m_ovWait.hEvent = CreateEvent(NULL, false, false, NULL); //SetCommMask设置要监控的事件 //EV_RXCHAR：输入缓冲区中已收到数据，即接收到一个字节并放入输入缓冲区。 //EV_ERR：线路状态错误，包括了CE_FRAME / CE_OVERRUN / CE_RXPARITY 3种错误。 SetCommMask(hCom, EV_ERR | EV_RXCHAR); //_beginThreadex创建读取线程 m_Thread = (HANDLE)_beginthreadex(NULL, 0, &My_Com::ComRecv, this, 0, NULL); m_IsOpen = true; return TRUE; } bool My_Com::ComWrite(LPBYTE buf, int &len) { BOOL rtn = FALSE; DWORD WriteSize = 0; //DWORD 代表 unsigned long PurgeComm(hCom, PURGE_TXCLEAR | PURGE_TXABORT); m_ovWait.Offset = 0; rtn = WriteFile(hCom, buf, len, &WriteSize, &m_ovWrite); if (FALSE == rtn && GetLastError() == ERROR_IO_PENDING)//后台读取 { //等待数据写入完成 printf("已发送 ："); for (int i = 0; i < len; i++) printf("%d ", buf[i]); printf("\n"); } return rtn != FALSE; } unsigned int __stdcall My_Com::ComRecv(void* LPParam) { My_Com *obj = static_cast<My_Com*>(LPParam); DWORD WaitEvent = 0, Bytes = 0; BOOL Status = FALSE; BYTE ReadBuf[4096]; DWORD Error; COMSTAT cs = { 0 }; int i; while (obj->m_IsOpen) { WaitEvent = 0; obj->m_ovWait.Offset = 0; Status = WaitCommEvent(obj->hCom, &WaitEvent, &obj->m_ovWait); /* WaitCommEvent等待串口通信事件的发生 用途：用来判断用SetCommMask()函数设置的串口通信事件是否已发生。 原型：BOOL WaitCommEvent(HANDLE hFile,LPDWORD lpEvtMask,LPOVERLAPPED lpOverlapped); 参数说明： -hFile：串口句柄 -lpEvtMask:函数执行完后如果检测到串口通信事件的话就将其写入该参数中。 -lpOverlapped：异步结构，用来保存异步操作结果。 */ //GetLastError()函数返回ERROR_IO_PENDING,表明串口正在进行读操作 if (FALSE == Status && GetLastError() == ERROR_IO_PENDING) { // GetOverlappedResult函数的最后一个参数设为TRUE，函数会一直等待，直到读操作完成或由于错误而返回。 Status = GetOverlappedResult(obj->hCom, &obj->m_ovWait, &Bytes, TRUE); } //在使用ReadFile 函数进行读操作前，应先使用ClearCommError函数清除错误。 ClearCommError(obj->hCom, &Error, &cs); if (TRUE == Status //等待事件成功 && WaitEvent&EV_RXCHAR//缓存中有数据到达 && cs.cbInQue > 0)//有数据 { Bytes = 0; obj->m_ovRead.Offset = 0; memset(ReadBuf, 0, sizeof(ReadBuf)); /* BOOL ReadFile( HANDLE hFile, //串口的句柄 LPVOID lpBuffer,// 读入的数据存储的地址,即读入的数据将存储在以该指针的值为首地址的一片内存区 DWORD nNumberOfBytesToRead,// 要读入的数据的字节数 LPDWORD lpNumberOfBytesRead,// 指向一个DWORD数值，该数值返回读操作实际读入的字节数 LPOVERLAPPED lpOverlapped // 重叠操作时，该参数指向一个OVERLAPPED结构，同步操作时，该参数为NULL ); */ Status = ReadFile(obj->hCom, &ReadBuf, 4096, &Bytes, &obj->m_ovRead); if (Status != FALSE) { printf("收到 ："); for (i = 0; i < Bytes; i++) { printf("%d ", ReadBuf[i]); } printf("\n"); } //PurgeComm函数清空串口的输入输出缓冲区 PurgeComm(obj->hCom, PURGE_RXCLEAR | PURGE_RXABORT); } } return 0; } void My_Com::Close_Com() { m_IsOpen = false; if (INVALID_HANDLE_VALUE != hCom) { CloseHandle(hCom); hCom = INVALID_HANDLE_VALUE; } if (NULL != m_ovRead.hEvent) { CloseHandle(m_ovRead.hEvent); m_ovRead.hEvent = NULL; } if (NULL != m_ovWrite.hEvent) { CloseHandle(m_ovWrite.hEvent); m_ovWrite.hEvent = NULL; } if (NULL != m_ovWait.hEvent) { CloseHandle(m_ovWait.hEvent); m_ovWait.hEvent = NULL; } if (NULL != m_Thread) { WaitForSingleObject(m_Thread, 5000);//等待线程结束 CloseHandle(m_Thread); m_Thread = NULL; } } LPCWSTR stringToLPCWSTR(std::string orig) { size_t origsize = orig.length() + 1; const size_t newsize = 100; size_t convertedChars = 0; wchar_t *wcstring = (wchar_t *)malloc(sizeof(wchar_t)*(orig.length() - 1)); mbstowcs_s(&convertedChars, wcstring, origsize, orig.c_str(), _TRUNCATE); return wcstring; }