MagTek 99875125 - Manual (Page 65)

Section 5. Example Applications
HANDLE oev_write = CreateEvent(NULL,TRUE,FALSE,NULL);
OVERLAPPED ov_write;
DWORD dwWriteStatus=0;
ZeroMemory(&ov_write, sizeof (OVERLAPPED));
ov_write.hEvent = oev_write;
DWORD dwLen = strlen(lpParam);
BOOL bDone=FALSE;
while (!bDone)
{
if (!WriteFile(*phMTD, lpParam,dwLen,lpdwWritten,&ov_write))
{
dwWriteStatus = WaitForSingleObject (ov_write.hEvent,COMM_TIMEOUT);
switch (dwWriteStatus)
{
case WAIT_OBJECT_0:
{
GetOverlappedResult(phMTD,&ov_write, lpdwWritten, TRUE);
bDone=TRUE;
}
break ;
default :
{
//No data was writted to the serial port
return FALSE;
}
};
}
bDone=TRUE;
}
return TRUE;
}
//----------------------------------------------------------------------------------
BOOL ReadMTD(PHANDLE phMTD, LPTSTR lpParam,DWORD pdwReadSize,DWORD *lpdwRead)
{
if (phMTD==INVALID_HANDLE_VALUE)
{
return FALSE;
}
BOOL
bDone=FALSE;
HANDLE oev_read = CreateEvent(NULL,TRUE,FALSE,NULL);
OVERLAPPED ov_read;
DWORD dwReadStatus=0;
ZeroMemory(&ov_read, sizeof (OVERLAPPED));
ov_read.hEvent = oev_read;
while (!bDone)
{
if (!ReadFile(*phMTD, lpParam, pdwReadSize,lpdwRead, &ov_read))
{
dwReadStatus = WaitForSingleObject (ov_read.hEvent, COMM_TIMEOUT);
switch (dwReadStatus)
{
case WAIT_OBJECT_0:
{
GetOverlappedResult(phMTD,&ov_read, lpdwRead, FALSE);
bDone=TRUE;
}
break ;
default :
{
//No data was read from the serial port
return FALSE;
}
};
}
bDone=TRUE;
}
return TRUE;
}
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