SerialPort.h

#include <Windows.h>
#include <atlstr.h>

#define BUFFER_SIZE 128

class CSerialPort
{
public:
    CSerialPort(void);
    virtual ~CSerialPort(void);

private:
    HANDLE  m_hComm;
    DCB     m_dcb;
    COMMTIMEOUTS m_CommTimeouts;
    bool    m_bPortReady;
    bool    m_bWriteRC;
    bool    m_bReadRC;
    DWORD   m_iBytesWritten;
    DWORD   m_iBytesRead;
    DWORD   m_dwBytesRead;

public:
    void ClosePort();
    bool ReadByte(BYTE &resp);
    bool ReadByte(BYTE* &resp, UINT size);
    bool WriteByte(char bybyte);
    bool OpenPort(CString portname);
    bool SetCommunicationTimeouts(DWORD ReadIntervalTimeout,
        DWORD ReadTotalTimeoutMultiplier, DWORD ReadTotalTimeoutConstant,
        DWORD WriteTotalTimeoutMultiplier, DWORD WriteTotalTimeoutConstant);
    bool ConfigurePort(DWORD BaudRate, BYTE ByteSize, DWORD fParity,
        BYTE  Parity, BYTE StopBits);
};