#include "stdafx.h"
#include "CommUtils.h"
#include "stdio.h"
const int READ_TIMEOUT = 500;
CommUtils::CommUtils()
{
bOpenCom = false;
}
CommUtils::~CommUtils()
{
this->CloseCom();
}
bool CommUtils::OpenCom(int Port)
{
if (bOpenCom)
{
this->CloseCom();
bOpenCom = false;
}
char szport[10];
sprintf(szport,"COM%d",Port);
hComm = CreateFile( szport,GENERIC_READ|GENERIC_WRITE, 0,NULL,OPEN_EXISTING,FILE_FLAG_OVERLAPPED,NULL);
int error=GetLastError();
if (hComm == INVALID_HANDLE_VALUE) return false;
if (!SetupComm(hComm, 1024, 512)) return false;
COMMTIMEOUTS commtimeouts;
commtimeouts.ReadIntervalTimeout = MAXDWORD;
commtimeouts.ReadTotalTimeoutConstant =0;
commtimeouts.ReadTotalTimeoutMultiplier =0;
commtimeouts.WriteTotalTimeoutConstant =0;
commtimeouts.WriteTotalTimeoutMultiplier=0;
if (!SetCommTimeouts(hComm, &commtimeouts)) return false;
memset(&ReadovReady,0,sizeof(OVERLAPPED));
memset(&WriteovReady,0,sizeof(OVERLAPPED));
ReadovReady.hEvent = CreateEvent(NULL,TRUE,FALSE,NULL);
WriteovReady.hEvent =CreateEvent(NULL,TRUE,FALSE,NULL);
SECURITY_ATTRIBUTES sa;
sa.nLength=sizeof(SECURITY_ATTRIBUTES);
sa.lpSecurityDescriptor=NULL;
sa.bInheritHandle=TRUE;
DCB dcb;
GetCommState(hComm, &dcb);
dcb.fBinary = TRUE;
dcb.fParity = TRUE;
dcb.BaudRate = CBR_9600; // baud rate 9600
dcb.ByteSize = 8;
dcb.Parity = NOPARITY;
dcb.StopBits = ONESTOPBIT;
if (!SetCommState(hComm, &dcb )) return false;
bOpenCom = true;
return bOpenCom;
}
bool CommUtils::WriteCom(unsigned char *sendchar, int sendsize)
{
if (!bOpenCom) return false;
DWORD BytesSent;
DWORD resD;
PurgeComm(hComm, PURGE_RXCLEAR | PURGE_TXCLEAR | PURGE_RXABORT | PURGE_TXABORT);
BytesSent=0;
BOOL hr = WriteFile(hComm, // Handle to COMM Port
sendchar, // Pointer to message buffer in calling finction
sendsize, // Length of message to send
&BytesSent, // Where to store the number of bytes sent
&WriteovReady); // Overlapped structure
if(!hr)
{
if(GetLastError() != ERROR_IO_PENDING)
{
return false;
}
else
{
resD=WaitForSingleObject(WriteovReady.hEvent,INFINITE);
}
switch(resD)
{
case WAIT_OBJECT_0:
{
if(!GetOverlappedResult(hComm,&WriteovReady,&BytesSent,false))
return false;
else
return true;
}
default:
return false;
break;
}
}
return true;
}
void CommUtils::CloseCom()
{
if (!bOpenCom) return;
CloseHandle(hComm);
hComm=NULL;
CloseHandle(ReadovReady.hEvent);
CloseHandle(WriteovReady.hEvent );
ReadovReady.hEvent =NULL;
WriteovReady.hEvent =NULL;
}
bool CommUtils::ReadCom(unsigned char * ReceiveData, DWORD& ReceiveLength)
{
if (!bOpenCom) return false;
if (ReadovReady.hEvent == NULL) return false;
ReceiveLength = 0;
if (ReadFile(hComm, ReceiveData, 128, &ReceiveLength, &ReadovReady) == FALSE)
{
if (GetLastError() != ERROR_IO_PENDING) return false;
}
/*
bResult = ReadFile(port->m_hComm, // Handle to COMM port
&RXBuff, // RX Buffer Pointer
1, // Read one byte
&BytesRead, // Stores number of bytes read
&port->m_ov); // pointer to the m_ov structure
// deal with the error code */
if(ReceiveLength == 0) return false;
ReceiveData[ReceiveLength] = 0;
DWORD dwRead;
DWORD dwRes = WaitForSingleObject(ReadovReady.hEvent, READ_TIMEOUT);
switch(dwRes)
{
case WAIT_OBJECT_0:
if (!GetOverlappedResult(hComm, &ReadovReady, &dwRead, FALSE)) return false;
break;
case WAIT_TIMEOUT:
break;
default:
break;
}
return true;
}
