简易串口读取代码

/********[e-mail]*******/#include <stdio.h>#include <stdlib.h>#include <windows.h>#define COM "COM9"/******must change here by your com_id*******/#undef DEBUG_ENABLE    #ifdef DEBUG_ENABLE  #define Debug(fmt,args...) printf("[zpx debug] "fmt"\n",##args)    #else  #define Debug(fmt,args...)#endif#define MAX_RANGE(x,y) ((x)>(y)?(y):(x))static int image_full_flag=0;unsigned char buff[256*256];int  read_com(HANDLE hFile){  DWORD dwNumRead=0;  DWORD dwErr=0;  int b=2,i;  static int firstFrame=1;  static int pixSum=0;   COMSTAT comStat;  b=ClearCommError(hFile,&dwErr,&comStat);  if(comStat.cbInQue==0)return 1;    Debug("b=%d,dwErr=%d,comStat.cbInQue=%d",b,(int)dwErr,(int)comStat.cbInQue);  OVERLAPPED readOverlapped;    readOverlapped.hEvent=CreateEvent(NULL,TRUE,FALSE,NULL);  //Sleep(10);  b=ReadFile(hFile,buff,comStat.cbInQue,&dwNumRead,&readOverlapped);  Debug("ReadFile=%d",b);   if(!b)  {    if(GetLastError()==ERROR_IO_PENDING){         Debug("GetLastError==ERR_IO_PENDING==%ld",ERROR_IO_PENDING);        GetOverlappedResult(hFile,&readOverlapped,&dwNumRead,TRUE);     }                else {       Debug("GetLastError()==%d",(int)GetLastError());       free(buff);       return 0;        }          }     Debug("dwNumRead=%d",(int)dwNumRead);  Debug("\n==================show msg==========================\n");  for(i=0;i<comStat.cbInQue;i++)               printf("%X ",buff[i]);  Debug("\n==================show msg==========================\n");/******you should set MY_DATA_PROCESS undef**/#define MY_DATA_PROCESS#ifdef MY_DATA_PROCESS    pixSum+=comStat.cbInQue;  if(firstFrame!=0)  {    if(comStat.cbInQue==1)    {      if(firstFrame==2)       {              firstFrame=0;         if(pixSum==96*96*2+2) {             image_full_flag=1;            printf("\ndon't skip first frame\n");            pixSum=0 ;            return 1;         }         pixSum=0;         return 0;      }      if(buff[comStat.cbInQue-1]>=0xfd)firstFrame=2 ;    }    else if(buff[comStat.cbInQue-1]==0xfd&&buff[comStat.cbInQue-2]==0xfe)    {            firstFrame=0;      if(pixSum==96*96*2+2) {             image_full_flag=1;            printf("\ndon't skip first frame\n");      }      else printf("\nskip first frame\n");            pixSum=0;    }      }  else{        if(pixSum==96*96*2+2){ //must remove 2Byte data in the end ;        pixSum=0;        image_full_flag=1;        printf("\nget full image\n");      }    }#endif  return 1;} void SetDcbInfo(HANDLE hFile,OVERLAPPED waitOverlapped){     int b;   DWORD dwMask=EV_RXCHAR;      while(1)   {      SetEvent(waitOverlapped.hEvent) ;     WaitCommEvent(hFile,&dwMask,&waitOverlapped);     WaitForSingleObject(waitOverlapped.hEvent,INFINITE);     ResetEvent(waitOverlapped.hEvent);     if(dwMask==EV_RXCHAR)     {                b=read_com(hFile);         if(b==1) break;            }        }  }                                                                           int main(int argc,char **argv){  static HANDLE hFile;  int getFileHandle=-1,cnt=0;  while(1)  {       hFile=CreateFile(COM,GENERIC_READ|GENERIC_WRITE,0,NULL,OPEN_EXISTING,                          FILE_ATTRIBUTE_NORMAL|FILE_FLAG_OVERLAPPED,NULL);      getFileHandle=(int)hFile;      if(getFileHandle!=-1)break;      Debug("Can't get %s %d times,Please check the Device!",COM,cnt++);      Sleep(1000);  }                    Debug("hFile=%d",(int)hFile);  DCB *dcb=(DCB*)malloc(1*sizeof(DCB));  GetCommState(hFile,(LPDCB)dcb);  dcb->BaudRate=CBR_57600;  dcb->ByteSize=8;//数据位8bit  dcb->StopBits=ONESTOPBIT;//停止位 1bit  dcb->Parity=NOPARITY;// 校验位  SetCommState(hFile,(LPDCB)dcb);     GetCommState(hFile,(LPDCB)dcb);  PurgeComm(hFile,PURGE_RXCLEAR);  SetCommMask(hFile,EV_RXCHAR);  printf("wait for rs232 event\n");  OVERLAPPED waitOverlapped;     waitOverlapped.hEvent=CreateEvent(NULL,TRUE,FALSE,NULL);  for(;;)  {     SetDcbInfo(hFile,waitOverlapped);     if(image_full_flag)     {        image_full_flag=0;        break;      }  }  Debug("get rs232 event");  system("pause");  free(dcb);  return 0;}

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