/* Receiver.c
   Program to Receive a Character using the Transceiver Module
 */
// Included files
#include <avr/interrupt.h>
#include <avr/io.h>
#include <util/delay.h>
#include "oi.h"

#define USB 1
#define CR8 2

// Constants
#define TRUE 1
#define FALSE 0

void delay10ms(uint16_t delay_10ms);
uint8_t byteRx(void);
void byteTx(uint8_t value);
void writeChar(char c, uint8_t com);
uint8_t getSerialDestination(void);
void delay(void);
void setSerial(uint8_t com);





void main(void)
{
	uint16_t i=0;
	uint8_t rx_data;
	uint8_t buffer[1000];
	uint8_t start = 1;
	
	uint8_t byte_count = 0;
       uint16_t array_count = 0;
	uint16_t j=0;
	uint8_t Start_Flag = FALSE,Stop_Flag = TRUE; 

	uint8_t temp =0x00;

	/*SET THE SERIAL PORT PARAMETERS TO COMMUNIATE WITH THE PC*/
	
	UBRR0 = 19;
	UCSR0B = 0x18;
	UCSR0C = 0x06;
	DDRB = 0X10;
	PORTB = 0X10;
	
	/*Connect the Receive Pin of the Transceiver to PORTC PIN0 */
	/*PC0 must be configured in input mode*/

	DDRC = 0XFF;
	PORTC =0XFF;
	DDRC = 0XFE;

	while(1)
	{	
	
		for(i=0;i<=20;i++)
			{
			buffer[i] = 0x01;
			//read_string[i] = 0X00;
			}
		
		i=0;	


		/*Do nothing till a start bit is detected*/
		temp =0X00;
		
		do
		{
		
		} while((PINC & 0X01)== 0x01);
		
		
		/*Start storing all the bits once a start bit has been detected*/
		while(i<= 50)
		{	
			_delay_us(417);
			buffer[i] = PINC & 0X01;
			_delay_us(417);
			//writeChar((rx_data+48),USB);
			i = i + 1;
		}
		writeChar(13,USB);
				
		/*Initialise start flag to false and stop flag to true*/
		Start_Flag = FALSE;
        Stop_Flag = TRUE;
        byte_count = 0;
        array_count = 0;
        i=0;

               do
               {
                     if( (Start_Flag == TRUE)&& (Stop_Flag == FALSE))
                     {
							  /*Once a stop bit is detcted, send the bult character to PC*/
                             if(byte_count == 8)
                             {
                                       if(buffer[i] == 0x01)
                                        {
                                   		writeChar(temp,USB);
                                        Stop_Flag = TRUE;
                                        Start_Flag = FALSE;
								        }
                              }
                     
							 /*Store 8 bits after a start bit into a temp varible and combine 
							   them to form the character*/
                             if(byte_count <= 7)
                             {
			
									 if(buffer[i] == 0x00)
                                     {
          								 temp =   (temp >> 1) | 0x00;
		                             }
                                       if(buffer[i] == 0x01)
                                       {
                 					    temp  =  (temp >> 1) | 0x80;
					                   }
                                 byte_count = byte_count  + 1;
                               }
					  }          
                      if((Start_Flag == FALSE)&& (Stop_Flag == TRUE) )
                     {
						/*Once a start bit has been detected in the buffer*/
                        if(buffer[i] == 0x00)
						{
							Start_Flag = TRUE;
							Stop_Flag = FALSE;
							array_count = array_count + 1;
							byte_count=0;
                        }
                        if(buffer[i] == 0x01)
                        {
                        }
                     }
                     
                  i = i + 1 ;
               
               }while(i<=50);
	}
}

void initialize(void)
{
  // Turn off interrupts
  cli();

  // Configure the I/O pins
  DDRB = 0x10;
  PORTB = 0xCF;
  DDRC = 0x02;
  PORTC = 0xFF;
  DDRD = 0xE6;
  PORTD = 0x7D;

  // Set up the serial port for 57600 baud
  UBRR0 = Ubrr57600;
  UCSR0B = (_BV(TXEN0) | _BV(RXEN0));
  UCSR0C = (_BV(UCSZ00) | _BV(UCSZ01));
}

void powerOnRobot(void)
{
  // If Create's power is off, turn it on
  if(!RobotIsOn)
  {
      while(!RobotIsOn)
      {
          RobotPwrToggleLow;
          delay10ms(50);  // Delay in this state
          RobotPwrToggleHigh;  // Low to high transition to toggle power
          delay10ms(10);  // Delay in this state
          RobotPwrToggleLow;
      }
      delay10ms(350);  // Delay for startup
  }
}

void baud28k(void)
{
  // Send the baud change command for 28800 baud
  
  	writeChar(CmdBaud, CR8);
  
  	writeChar(Baud19200, CR8);

  // Wait while until the command is sent
  while(!(UCSR0A & _BV(TXC0))) ;

  // Change the atmel's baud rate
  UBRR0 = Ubrr19200;

  // Wait 100 ms
  delay10ms(10);
}

void delay10ms(uint16_t delay_10ms)
{
  // Delay for (delay_10ms * 10) ms
  while(delay_10ms-- > 0)
  {
    // Call a 10 ms delay loop
    _delay_loop_2(46080);
  }
}

uint8_t byteRx(void)
{
  // Receive a byte over the serial port (UART)
  while(!(UCSR0A & _BV(RXC0))) ;
  return UDR0;
}

void flushRx(void)
{
  uint8_t temp;

  // Clear the serial port
  while(UCSR0A & _BV(RXC0))
    temp = UDR0;
}

void byteTx(uint8_t value)
{
  // Send a byte over the serial port
  while(!(UCSR0A & _BV(UDRE0))) ;
  UDR0 = value;
}

uint8_t getSerialDestination(void)
{
	if (PORTB & 0x10)
	return USB;
	else
	return CR8;
}

void delay(void)
{
int i=0,j=0;
	for(i=1;i<=1000;i++)
	{
		for(j=1;j<=1000;j++)
		{
		} 
	}
}

void writeChar(char c, uint8_t com)
{
	uint8_t originalDestination = getSerialDestination();
	if (com != originalDestination)
	{
	setSerial(com);
	delay();
	}
	byteTx((uint8_t)(c));
	if (com != originalDestination)
	{
		setSerial(originalDestination);
		delay();
	}
}

void setSerial(uint8_t com)
{
	if(com == USB)
	PORTB |= 0x10;
	else if(com == CR8)
	PORTB &= ~0x10;
}

void SendStringtoPC(char *Message)
{
	setSerial(USB);
	while(*Message)
	{
		 while(!(UCSR0A & _BV(UDRE0))) ;
		UDR0 = *Message;
		Message++;
	}
}
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