#include "StdAfx.h"
#include "serialport.h"

// default constructer... not much to do right now but set our handle (hComm) to NULL
SerialPort::SerialPort()
{
	hComm = NULL;
}

// destructor which will automatically close the serial port incase the user forgot to do so manually...
SerialPort::~SerialPort(void)
{
	Close();
}

// will close the serial port if it is open
void SerialPort::Close()
{
	if(hComm)
	{
		CloseHandle(hComm);
		hComm = NULL;
	}
}

// The following will open the serial port using the settings specified within COMPort (see SerialPort.h for more info on this)
bool SerialPort::InitSerialPort(SetupPort COMPort)
{
	hComm = CreateFile(_T("COM1:"), GENERIC_READ | GENERIC_WRITE, 0, NULL, OPEN_EXISTING, 0, NULL);
	if(hComm == INVALID_HANDLE_VALUE)
		return false;	// Something went wrong, so quit

	DCB options;
	if(GetCommState(hComm, &options) == 0)	// try to get the current settings for the COM port
	{
		MessageBox(NULL, _T("InitSerialPort Error 0x02"),_T("Error"),MB_OK);	// didn't work, so quit
		CloseHandle(hComm);
		hComm = NULL;
		return false;
	}

	// OK, so now change these settings to the ones specified by COMPort
	options.BaudRate = COMPort.BaudRate;
	options.ByteSize = COMPort.ByteSize;
	options.Parity = COMPort.Parity;
	options.StopBits = COMPort.StopBits;
	options.fBinary = TRUE;
	options.fDsrSensitivity = false;
	options.fParity = COMPort.fParity;
	options.fOutX = false;
	options.fInX = false;
	options.fNull = false;
	options.fAbortOnError = true;
	options.fOutxCtsFlow = TRUE;
	options.fOutxDsrFlow = false;
	options.fDtrControl=DTR_CONTROL_ENABLE;
	options.fDsrSensitivity=false;
	options.fRtsControl=RTS_CONTROL_HANDSHAKE;
	options.fOutxCtsFlow=false;

	// And set the settings:
	if(SetCommState(hComm, &options) == 0)
	{
		MessageBox(NULL, _T("InitSerialPort Error 0x03"),_T("Error"),MB_OK);
		CloseHandle(hComm);
		hComm = NULL;
		return false;
	}

	// setup the timeouts:
	COMMTIMEOUTS timeOuts;
	if((GetCommTimeouts (hComm, &timeOuts))==0)
		return false;
	timeOuts.ReadIntervalTimeout = 0;
	timeOuts.ReadTotalTimeoutConstant = 10;
	timeOuts.ReadTotalTimeoutMultiplier = 10;
	timeOuts.WriteTotalTimeoutConstant = 1000;
	timeOuts.WriteTotalTimeoutMultiplier= 10;
	if(SetCommTimeouts (hComm, &timeOuts) == 0)
	{
		MessageBox(NULL, _T("InitSerialPort Error 0x04"),_T("Error"),MB_OK);
		CloseHandle(hComm);
		hComm = NULL;
		return false;
	}
	return true;	// done and all went well!
}

// This will send a single byte of data over the serial port
bool SerialPort::SendByte(char data)
{
	if(!hComm)
		return false;	// COM port not open, so quit

	DWORD bytesWritten = 0;
	if(WriteFile(hComm, &data, 1, &bytesWritten, NULL) == 0)
		return false;

	return true;
}

// This will check to see if there is anything to read in from the COM port
// If there is data to read, that byte is stored in data, and this returns a TRUE
// Otherwise a FALSE is returned and data is unaffected
bool SerialPort::ReadByte(char *data)
{
	BYTE b;

	DWORD bytesTransferred=0;

	if(ReadFile(hComm, &b, 1, &bytesTransferred, 0))
	{
		if (bytesTransferred == 1)
		{
			*data=b;
			return true;
		}
	}
	return false;
}

#pragma once

// SerialPort.h written by Walter O. Krawec
// with thanks to this article which provided a ton of info on this topic:
// http://www.codeguru.com/Cpp/I-N/network/serialcommunications/article.php/c5395/
//
// USAGE:
// SerialPort Name;
//
// -- In WinMain --
// Name.InitSerialPort(SetupPort());
//
// -- on closing --
// Name.Close();
//
// -- to send a byte --
// Name.SendByte(BYTE_TO_SEND);
//
// -- to recv a byte --
// char c=0;
// Name.RecvByte(&c);	// returns TRUE if a byte was received.

// SetupPort is a structure holding basic COM port settings including
// baud rate, parity, etc.
struct SetupPort
{
	BYTE PortNum;
	BYTE ByteSize;
	BYTE Parity;
	BYTE StopBits;
	DWORD BaudRate;
	DWORD fParity;

	SetupPort()	// Default constructer loads default settings of (9600, 8, N, 1)
	{
		PortNum = 1; ByteSize = 8; Parity = NOPARITY; StopBits = ONESTOPBIT;
		BaudRate = 9600; fParity = false;
	}
	SetupPort(DWORD baudRate, BYTE byteSize, BYTE parity, BYTE stopBits)	// Setup basic options manually
	{
		PortNum = 1; ByteSize = byteSize; Parity = parity; StopBits = stopBits;
		BaudRate = 9600; fParity = false;
	}
};

// SerialPort is the main class responsible for communicating via the serial port on a PPC or PC
class SerialPort
{
public:
	SerialPort(void);
	~SerialPort(void);

	void Close();
	bool InitSerialPort(SetupPort COMPort);
	bool SendByte(char data);		// sends one byte of data through the COM port (call InitSerialPort first)
	bool ReadByte(char *data);		// recvs one byte of data through the COM port (call InitSerialPort first)

private:
	HANDLE hComm;				// handle to the serial port
};