Win32 API串口编程

来源：互联网发布：golang mgo find 编辑：程序博客网时间：2024/05/04 11:25

原文地址::http://blog.csdn.net/zhuyonghao123/article/details/8162250

相关网帖

1.Win32串口编程----http://www.vckbase.com/index.php/wv/1439

通常windows下串口编程大家会选择MFC使用SCOM控件进行串口操作，

方便而且简单，我也是这样的，PC端要进行串口编程就选择MFC做一个

简单的界面，添加SCOM控件。但有时我们需要在Win32下进行串口编程，

根据我在网上查的资料以及编程调试经验做一个简单的例子，需要深入的

可以此为基础。

串口编程的过程基本是这样的：

串口打开、串口读操作、串口写操作、串口关闭

包含头文件：

#include <windows.h>

#include <stdio.h>

一、串口的同步方式(等待操作完成后才能返回)：

1、打开串口—同步方式

HANDLE Open_driver_T(char *name)

{

//打开串口

HANDLE m_hCom = CreateFile(name,GENERIC_READ | GENERIC_WRITE, 0, NULL,

OPEN_EXISTING, 0, NULL);

if(m_hCom == INVALID_HANDLE_VALUE)

{

printf("Create File faile\n");

return NULL;

}

//设置缓冲区大小

if(!SetupComm(m_hCom,1024,1024))

{

printf("SetupComm fail!\n");

CloseHandle(m_hCom);

return NULL;

}

//设置超时

COMMTIMEOUTS TimeOuts;

memset(&TimeOuts,0,sizeof(TimeOuts));

TimeOuts.ReadIntervalTimeout = 100;

TimeOuts.ReadTotalTimeoutConstant = 1000;

TimeOuts.ReadTotalTimeoutMultiplier = 100;

TimeOuts.WriteTotalTimeoutConstant = 2000;

TimeOuts.WriteTotalTimeoutMultiplier = 50;

SetCommTimeouts(m_hCom,&TimeOuts);

PurgeComm(m_hCom,PURGE_TXCLEAR|PURGE_RXCLEAR);

//设置串口参数

DCB dcb = {0};

if (!GetCommState(m_hCom,&dcb))

{

printf("GetCommState fail\n");

return NULL;

}

dcb.DCBlength = sizeof(dcb);

if (!BuildCommDCB("1228800,n,8,1",&dcb))//填充ＤＣＢ的数据传输率、奇偶校验类型、数据位、停止位

{

printf("BuileCOmmDCB fail\n");

CloseHandle(m_hCom);

return NULL;

}

if(SetCommState(m_hCom,&dcb))

{

printf("SetCommState OK!\n");

}

return m_hCom;

}

2、串口发送(写操作)--同步方式

unsigned char Send_driver_T(HANDLE fd, BYTE *data)

{

DWORD dwError;

DWORD dwExpectSend = 20;

DWORD dwRealSend = 0;

BYTE *pSendBuffer;

pSendBuffer = data;

if(ClearCommError(fd,&dwError,NULL))

{

PurgeComm(fd,PURGE_TXABORT | PURGE_TXCLEAR);

}

if(!WriteFile(fd,pSendBuffer,dwExpectSend ,&dwRealSend,NULL))

{

//写串口失败

printf("发送失败!\n");

return 1;

}

return 0;

}

3、串口读取(读操作)--同步方式

unsigned char Receive_driver_T(HANDLE fd, BYTE *data)

{

DWORD dwError;

DWORD dwWantRead = 20;

DWORD dwRealRead = 0;

BYTE* pReadBuf;

int i;

BYTE crc;

pReadBuf = data;

if (ClearCommError(fd,&dwError,NULL))

{

PurgeComm(fd,PURGE_TXABORT | PURGE_TXCLEAR);

}

if(!ReadFile(fd,pReadBuf,dwWantRead ,&dwRealRead,NULL)) //成功返回非0 //失败返回0

{

return 1;

}

if(dwRealRead>0)

printf("recv_len = %d\n",dwRealRead);

printf("接收数据: ");

for(i=0; i<20; i++)

{

printf("%x ",data[i]);

}

printf("\n");

return 0;

}

4、串口关闭

int Close_driver(void *fd)

{

CloseHandle(fd);

return 0;

}

5、编程应用程序

void main()

{

HANDLE hCom;

BYTE SendData[20] = {0};

BYTE RecvData[100] = {0};

unsigned int SendCnt=0;

unsigned int RecvCnt=0;

int i;

hCom = Open_driver_T("COM3");

if(!hCom)

{

printf("串口端口打开失败\n");

return ;

}

else

printf("串口端口打开成功!\n");

SendCnt=0;

for(i=0; i<5; i++)

{

SendCnt++;

if(Send_driver_T(hCom, SendData))

{

printf("数据(%4d) 发送失败!\n",SendCnt);

}

else

{

printf("数据(%4d) 发送成功!\n",SendCnt);

}

Sleep(1000);

}

printf("\n");

RecvCnt=0;

for(i=0; i<5; i++)

{

if(Receive_driver_T(hCom, RecvData))

{

printf("数据(%4d) 接收失败!\n",RecvCnt);

}

else

{

RecvCnt++;

printf("数据(%4d) 接收成功!\n",RecvCnt);

}

Sleep(1000);

}

二、串口的异步方式(操作结束立即返回)

1、打开串口—异步方式

HANDLE Open_driver_Y(char *name)

{

//打开串口

HANDLE m_hCom = CreateFile(name,GENERIC_READ | GENERIC_WRITE, 0, NULL,

OPEN_EXISTING, FILE_FLAG_OVERLAPPED, NULL);

if(m_hCom == INVALID_HANDLE_VALUE)

{

printf("Create File faile\n");

return NULL;

}

//设置缓冲区大小

if(!SetupComm(m_hCom,1024,1024))

{

printf("SetupComm fail!\n");

CloseHandle(m_hCom);

return NULL;

}

//设置超时

COMMTIMEOUTS TimeOuts;

memset(&TimeOuts,0,sizeof(TimeOuts));

TimeOuts.ReadIntervalTimeout = 100;

TimeOuts.ReadTotalTimeoutConstant = 1000;

TimeOuts.ReadTotalTimeoutMultiplier = 100;

TimeOuts.WriteTotalTimeoutConstant = 2000;

TimeOuts.WriteTotalTimeoutMultiplier = 50;

SetCommTimeouts(m_hCom,&TimeOuts);

PurgeComm(m_hCom,PURGE_TXCLEAR|PURGE_RXCLEAR);

//设置串口参数

DCB dcb = {0};

if (!GetCommState(m_hCom,&dcb))

{

printf("GetCommState fail\n");

return NULL;

}

dcb.DCBlength = sizeof(dcb);

if (!BuildCommDCB("1228800,n,8,1",&dcb))//填充ＤＣＢ的数据传输率、奇偶校验类型、数据位、停止位

{

printf("BuileCOmmDCB fail\n");

CloseHandle(m_hCom);

return NULL;

}

if(SetCommState(m_hCom,&dcb))

{

printf("SetCommState OK!\n");

}

//建立并初始化重叠结构

ZeroMemory(&wrOverlapped,sizeof(wrOverlapped));

if (wrOverlapped.hEvent != NULL)

{

ResetEvent(wrOverlapped.hEvent);

wrOverlapped.hEvent = CreateEvent(NULL,TRUE,FALSE,NULL);

}

return m_hCom;

}

2、串口发送(写操作)—异步方式

unsigned char Send_driver_Y(HANDLE fd, BYTE *data)

{

DWORD dwError;

DWORD dwExpectSend = 20;

DWORD dwRealSend = 0;

BYTE *pSendBuffer;

pSendBuffer = data;

if(ClearCommError(fd,&dwError,NULL))

{

PurgeComm(fd,PURGE_TXABORT | PURGE_TXCLEAR);

}

if(!WriteFile(fd,pSendBuffer,dwExpectSend ,&dwRealSend,&wrOverlapped))

{

if(GetLastError() == ERROR_IO_PENDING)

{

while(!GetOverlappedResult(fd,&wrOverlapped,&dwRealSend,FALSE))

//成功返回非0，失败返回0

{

if(GetLastError() == ERROR_IO_INCOMPLETE)

{

continue;

}

else

{

printf("发送失败!\n");

ClearCommError(fd,&dwError,NULL);

break;

return 1;

}

return 0;

}

3、串口接收(读操作)--异步方式

unsigned char Receive_driver_Y(HANDLE fd, BYTE *data)

{

DWORD dwError;

DWORD dwWantRead = 20;

DWORD dwRealRead = 0;

BYTE* pReadBuf;

int i;

BYTE crc;

pReadBuf = data;

if (ClearCommError(fd,&dwError,NULL))

{

PurgeComm(fd,PURGE_TXABORT | PURGE_TXCLEAR);

}

if(!ReadFile(fd,pReadBuf,dwWantRead,&dwRealRead,&wrOverlapped))

{

dwError=GetLastError();

if(dwError == ERROR_IO_PENDING)

{

while(!GetOverlappedResult(fd,&wrOverlapped,&dwRealRead,TRUE))

//成功返回非0, 失败返回0

{

return 1;

}

if(dwRealRead>0)

printf("recv_len = %d\n",dwRealRead);

printf("接收数据\n");

for(i=0; i<20; i++)

{

printf("%x ",data[i]);

}

return 0;

}

4、关闭串口

int Close_driver(void *fd)

{

CloseHandle(fd);

return 0;

}

5、编程应用程序--异步方式

OVERLAPPED wrOverlapped;

void main()

{

HANDLE hCom;

BYTE SendData[20] = {0};

BYTE RecvData[100] = {0};

unsigned int SendCnt=0;

unsigned int RecvCnt=0;

int i;

hCom = Open_driver_Y("COM3");

if(!hCom)

{

printf("串口端口打开失败\n");

return ;

}

else

printf("串口端口打开成功!\n");

SendCnt=0;

for(i=0; i<5; i++)

{

SendCnt++;

if(Send_driver_Y(hCom, SendData))

{

printf("数据(%4d) 发送失败!\n",SendCnt);

}

else

{

printf("数据(%4d) 发送成功!\n",SendCnt);

}

Sleep(1000);

}

printf("\n");

RecvCnt=0;

for(i=0; i<5; i++)

{

if(Receive_driver_Y(hCom, RecvData))

{

printf("数据(%4d) 接收失败!\n",RecvCnt);

}

else

{

RecvCnt++;

printf("数据(%4d) 接收成功!\n",RecvCnt);

}

Sleep(1000);

}

相关函数原型以及参数定义请参考MSDN

//===================================================

备注::

1.串口的操作可以有两种操作方式：同步操作方式和重叠操作方式（又称为异步操作方式）。同步操作时，API函数会阻塞直到操作完成以后才能返回（在多线程方式中，虽然不会阻塞主线程，但是仍然会阻塞监听线程）；而重叠操作方式，API函数会立即返回，操作在后台进行，避免线程的阻塞。

2.怎么都不见WaitCommEvent函数的使用？？？

3.怎么在一些书籍上看到在什么NT内核的WINDOWS系统上不支持串口的同步操作方式

4.我的ClearCommError函数老是获不得正确的数据个数，不知道为什么，不知道那里没设置好

5.串口通信出错网帖

1》串口收数据丢失----http://bbs.csdn.net/topics/120014380

2》串口通信接收数据丢失----http://bbs.csdn.net/topics/70081340

3》MSDN Serial Communications----http://msdn.microsoft.com/en-us/library/ff802693.aspx

4》ClearCommError函数问题----http://bbs.csdn.net/topics/390147651?page=1#post-394097054