Serial Port

//////////////////////////////////////////////HEADER///////////////////////////////////////
#ifndef __RS232_H_
#define __RS232_H_
#include <windows.h>

class ComPort{
  HANDLE hCom;
  int opened;
public:
  ~ComPort();
  ComPort();
  int Init(const char * comPortStr,int speed, int byteSize = 8, int parity = 0, int stopBit = 0);
  int SetBaudRate(int speed);
  void Close ();
  int Read(char * c,int num);
  int GetStatus();
  int Writef(char * str, ...);
  int Write(char *c, int num);
  int Write(char *c);
  int Write(char c);
  int SetRTS(int level);
  int SetDTR(int level);
  void ClearTxBuff();
  void ClearRxBuff();
};
#endif
////////////////////////////////////////////////////////////////////////////////////////////

#include "rs232.h"
#include <stdarg.h>
#include <stdio.h>

void ComPort::ClearTxBuff(){
  PurgeComm(hCom,PURGE_TXCLEAR);
}

void ComPort::ClearRxBuff(){
  PurgeComm(hCom,PURGE_RXCLEAR);
}

int ComPort::SetBaudRate(int speed){
  DCB dcb;
  GetCommState( hCom, &dcb );
  dcb.BaudRate = speed ;
  if ( !SetCommState( hCom, &dcb ) ){
//    CloseHandle(hCom);
    return 1;//SetCommState error
  }
  return 0;
}

int ComPort::GetStatus(){
  unsigned int stat;
  GetCommModemStatus(hCom, (LPDWORD)&stat);
  return stat;
}

int ComPort::SetRTS(int level){
  DCB dcb;
  GetCommState( hCom, &dcb );
  dcb.fRtsControl = level ? RTS_CONTROL_ENABLE : RTS_CONTROL_DISABLE;
  if ( !SetCommState( hCom, &dcb ) ){
//    CloseHandle(hCom);
    return 1;
  }
  return 0;
}

int ComPort::SetDTR(int level){
  DCB dcb;
  GetCommState( hCom, &dcb );
  dcb.fDtrControl = level ? DTR_CONTROL_ENABLE : DTR_CONTROL_DISABLE;
  if ( !SetCommState( hCom, &dcb ) ){
//    CloseHandle(hCom);
    return 1;
  }
  return 0;
}


ComPort::~ComPort(){
  Close();

}

ComPort::ComPort(){
  opened = 0;
}

int ComPort::Init(const char * comPortStr,int speed, int byteSize, int parity, int stopBit){
  DCB dcb;

  COMMTIMEOUTS  CommTimeOuts ;
  if ( ( hCom = CreateFile (comPortStr, GENERIC_READ | GENERIC_WRITE, 0, NULL, OPEN_EXISTING, 0, NULL ) )
               == INVALID_HANDLE_VALUE   ) {
     return 1; // error
  }
  CommTimeOuts.ReadIntervalTimeout = MAXDWORD;
  CommTimeOuts.ReadTotalTimeoutMultiplier = 0;
  CommTimeOuts.ReadTotalTimeoutConstant = 0;
  CommTimeOuts.WriteTotalTimeoutMultiplier = 0;
  CommTimeOuts.WriteTotalTimeoutConstant = 0;

  if ( !SetCommTimeouts( hCom, &CommTimeOuts )){
    CloseHandle(hCom);
    return 2; // SetCommTimeouts error
  }

  dcb.DCBlength = sizeof ( DCB ) ;
  dcb.BaudRate = speed ;
  dcb.fBinary = TRUE ;
  dcb.fParity = 0;
  dcb.fOutxCtsFlow = 0;         // CTS output flow control
  dcb.fOutxDsrFlow = 0;         // DSR output flow control
  dcb.fDtrControl =  DTR_CONTROL_ENABLE;         // DTR flow control type

  dcb.fDsrSensitivity = 0;      // DSR sensitivity
  dcb.fTXContinueOnXoff = 0;    // XOFF continues Tx
  dcb.fOutX = 0;                // XON/XOFF output flow control
  dcb.fInX = 0;                 // XON/XOFF input flow control

  dcb.fErrorChar = 0;           // enable error replacement
  dcb.fNull = 0;                // enable null stripping
  dcb.fRtsControl = RTS_CONTROL_ENABLE;          // RTS flow control

  dcb.fAbortOnError = 0;        // abort reads/writes on error
  dcb.XonLim = 0;            // transmit XON threshold
  dcb.XoffLim = 0;            // transmit XOFF threshold
  dcb.ByteSize = byteSize;      // number of bits/byte, 4-8
  dcb.Parity = parity;          // 0-4=no,odd,even,mark,space
  dcb.StopBits = stopBit;       // 0,1,2 = 1, 1.5, 2
  dcb.XonChar = 0;             // Tx and Rx XON character
  dcb.XoffChar = 0;            // Tx and Rx XOFF character
  dcb.ErrorChar = 0;            // error replacement character
  dcb.EofChar = 0;              // end of input character
  dcb.EvtChar = 0;              // received event character
  if ( !SetCommState( hCom, &dcb ) ){
    CloseHandle(hCom);
    return 3;//SetCommState error
  }
  opened = 1;
  return(0);
}

void ComPort::Close (){
  if (opened!=1) return;
  opened = 0;
  CloseHandle( hCom );
}

int ComPort::Read(char * c,int num){
  DWORD length = 0;
  if( !ReadFile(hCom, c, num, &length, NULL) ) return 0;
  return length;
}

int ComPort::Write(char *c, int num){
  DWORD length = 0;
  WriteFile(hCom, c, num, &length, NULL);
  return length;
}

int ComPort::Write(char c){
  DWORD length;
  return WriteFile(hCom, &c, 1, &length, NULL);
}

int ComPort::Write(char * c){
  DWORD length;
  int num = 0;
  while (c[num]) num += 1;
  return WriteFile(hCom, c, num, &length, NULL);
}

int ComPort::Writef(char * str, ...){
  char tmpStr[1024];
  va_list args;
  va_start (args, str);
  vsprintf_s (tmpStr, 1024, str, args);
  va_end (args);
  return Write(tmpStr);
}