/*
 * GccApplication1.c
 *
 * Created: 2016-04-13 08:35:42
 *  Author: digpi04
 */ 

#include <util/delay.h>
#include <avr/io.h>
#include <avr/interrupt.h>

unsigned char c;
unsigned int pulse; 
unsigned int count = 0;
unsigned int interruptCount = 0;
unsigned int top = 0;
unsigned int val;


void timerSetup(void)
{
	TCCR1A = 0;
	TCCR1B = 0;
	TCNT1 = 0x3CAF;
	TIMSK = 0x04; //Overflow interrupt enable
	TIFR = 0x04; //Overflow flag
}

void startTimer(void)
{
	TCCR1B = 0b00000010; //Sets prescaler to 8
}

void resetTimer(void) //Stops and resets timer
{	
	TCCR1B = 0;
	TCNT1 = 0x3CAF;
}

void counterSetup(void)
{
	TCCR0 = 0;
	TCNT0 = 0xFF;
	TCNT0 = 0;
}

void startCounter(void)
{
	TCCR0 = 0x07;	
}

void resetCounter(void) //Stops and clears counter
{	
	TCCR0 = 0;
	TCNT0 = 0;
}

void ELow()
{
	PORTA &= ~(1 << PA0); 
}

void EHigh()
{
	PORTA |= (1 << PA0); 
}

void RSLow()
{
	PORTA &= ~(1 << PA2); 
}

void RSHigh()
{
	PORTA |= (1 << PA2);
}

void RWLow()
{
	PORTA &= ~(1 << PA1);
}

void RWHigh()
{
	PORTA |= (1 << PA1);
}
	
void greenOn(void)
{
	PORTC |= (1 << PC1);
}

void redOn(void)
{
	PORTC |= (1 << PC0);
}

void yellowOn(void)
{
	PORTA |= (1 << PA4);
}

void greenOff(void)
{
	PORTC &= ~(1 << PC1);
}

void redOff(void)
{
	PORTC &= ~(1 << PC0);
}

void yellowOff(void)
{
	PORTA &= ~(1 << PA4);
}

int button()
{
	int val = PINB;
	int val1 = val & 0x04;
	if(val1 != 0)
	{ 
		return 1;
	}
	else
	{
	return 0;
	}
}

void writeLetter(char c)
{
	EHigh();
	RSHigh();
	PORTD = c;
	ELow();
}

void pulseNbr(int nbr)
{
	switch(nbr)
	{
		case 0:
		writeLetter(0x30);
		break;
		case 1:
		writeLetter(0x31);
		break;
		case 2:
		writeLetter(0x32);
		break;
		case 3:
		writeLetter(0x33);
		break;
		case 4:
		writeLetter(0x34);
		break;
		case 5:
		writeLetter(0x35);
		break;
		case 6:
		writeLetter(0x36);
		break;
		case 7:
		writeLetter(0x37);
		break;
		case 8:
		writeLetter(0x38);
		break;
		case 9:
		writeLetter(0x39);
		break;
	}
}

void pulseText(void)
{
	writeLetter(0x20); //" "
	_delay_us(10);
	writeLetter(0x73); //s
	_delay_us(10);
	writeLetter(0x6C); //l
	_delay_us(10);
	writeLetter(0x61); //a
	_delay_us(10);
	writeLetter(0x67); //g
	_delay_us(10);
	writeLetter(0x2F); //"/"
	_delay_us(10);
	writeLetter(0x6D); //m
	_delay_us(10);
	writeLetter(0x69); //i
	_delay_us(10);
	writeLetter(0x6E); //n
	_delay_us(10);
}

void display(int pulse) //Displays the pulse and text on the display
{
	int temp;
	
	int nbr = pulse/100; //nbr is the first digit of the pulse if it's more than 100
	if (nbr > 0 ) {
		pulseNbr(nbr); //Writes the first digit of the pulse
		temp = pulse - nbr*100; //Converts the rest of the pulse to two digits
		} else {
		temp = pulse;
	}
	nbr = temp/10; //nbr is the second digit of the pulse if it's more than 100, otherwise the first
	pulseNbr(nbr); //Writes the second digit of the pulse
	nbr = temp - nbr*10; //Converts the rest of the pulse to one digit
	_delay_us(10);
	pulseNbr(nbr); //Writes the last digit of the pulse
	_delay_us(10);
	pulseText(); //Writes the text slag/min
}

void setConverter(void)
{
	ADMUX = 0b11000111;
	ADCSRA = 0b11000110;
}

ISR(TIMER1_OVF_vect)
{
	//Reads the ADconverter and counts the interrrupts
	setConverter();	
	if((ADCSRA & 0b00010000) != 0)
	{		
		val = ADC;
		if(val >= 0x136 && top == 0)
		{
			top = 1;			
		} else if(val < 0x136 && top == 1) 
		{
			count ++;
			yellowOn();
			top = 0;
		}  else 
		{
			yellowOff();
		}
	}
	interruptCount++;
	resetTimer();
}

void clearDisplay(void)
{
	EHigh();
	RSLow();
	RWLow(); 
	PORTD = 0x01; // Sets DB0 to 1
	ELow();
}

void setDisplay(void)
{
	EHigh();
	RSLow();
	RWLow();
	PORTD = 0x30;
	ELow();
}

void displayOn(void)
{
	EHigh();
	RSLow();
	RWLow();
	PORTD = 0b00001111;
	ELow();
}

void homeCursor(void)
{
	EHigh();
	RSLow();
	RWLow();
	PORTD = 0x02;
	ELow();
}

void start(void)
{
	DDRA |= (1 << PA0); //Sets PA0 to outgoing
	DDRA |= (1 << PA1); //Sets PA1 to outgoing
	DDRA |= (1 << PA2); //Sets PA2 to outgoing
	DDRA &= ~(1 << PA7); //Sets PA7 to ingoing
	DDRA |= (1 << PA4); //Sets PA4 to outgoing
	DDRB &= ~(1 << PB2); // Sets PB2 to ingoing
	DDRC |= (1 << PC0); //Sets PC0 to outgoing
	DDRC |= (1 << PC1); //Sets PC1 to outgoing
	DDRD = 0xFF; //Sets all D-ports to outgoing
	_delay_us(50);
	displayOn();
	_delay_us(50);
	setDisplay();	
	_delay_us(50);
	clearDisplay();	
	_delay_ms(2);
	homeCursor();
	_delay_ms(2);
	sei();
	timerSetup();
	counterSetup();
}

int main(void)
{
	start();	
	while(1)
	{			
		int i = button();
		if(i == 1) {
			clearDisplay();
			//_delay_ms(2);			
			redOff();
			greenOff();
		}
		while (i == 1)
		{ 
			i = 1; 			
			startTimer();
			startCounter();
			if(interruptCount == 300)
			 {
				 yellowOff();
				 pulse = count*4;
				 display(pulse);
				 if(pulse > 85 || pulse < 60)
				 {
					 redOn();
				 } else
				 {
					 greenOn();
				 }
				 interruptCount = 0;
				 count = 0;
				 i = 0;				
			}	 			  	 		 
		}
	}
}