/*
 * Pulsmatare.c
 *
 * Created: 2015-04-13 14:33:40
 *  Author: digpi09
 */ 

#include <avr/io.h>
#include <avr/interrupt.h>
#include <util/delay.h>
unsigned char letter;
unsigned int pulse;

int checkButton()
{ 
	if(PINC & (1 << 0)) { //if button is pressed
		return 1;
	}
	return 0;
}

void pulseCountReady()
{	//Installations for 8-bit timer on T0:
	TCCR0 = 0x00; //Stops counter
	TCNT0 = 0xFF; //Setting 8-bit counter to read mode.
	TCNT0 = 0x00; //Clears counter
	
}

void resetCounter() 
{
	TCCR0 = 0x00; //Stops counter
	TCNT0 = 0x00; //Clears counter
}

void timerReady()
{	//Installations for 16-bit timer on T1:
	TCCR1A = 0x00; //Normal port operation for 16-bit timer
	TCCR1B = 0x00; //Stops timer
	TCNT1H = 0x67; //Setting the 16-bit timer to 26473 (bit 8-15)
	TCNT1L = 0x69; //Setting the 16-bit timer to 26473 (bit 0-7)
	TIMSK = 0x04; //Enabling overflow interrupt
	TIFR = 0x04; //Enabling overflow interrupt
}

void resetTimer()
{
	TCCR1B = 0x00; //Stops timer
	TCNT1H = 0x67; //Setting the 16-bit timer to 26473 (bit 8-15)
	TCNT1L = 0x69; //Setting the 16-bit timer to 26473 (bit 0-7)
}

void startTimer()
{
	TCCR1B = 0x05; //Enables clock source, sets prescaler to 1024
}

void startCounter()
{
	TCCR0 = 0x07; //Starts counter
}

ISR(TIMER1_OVF_vect)
{	//When interruption occurs after 10 seconds:
	pulse = TCNT0*6; //Saves pulse per minute
	PORTB &= ~_BV(PB4); //Turns off green LED
	resetTimer();
	resetCounter();
	pulseToDisplay(pulse); 
}

void numberHandler(int number)
{
	if(number == 0){
		writeLetter(0x30);
	}
	if(number == 1){
		writeLetter(0x31);
	}
	if(number == 2){
		writeLetter(0x32);
	}
	if(number == 3){
		writeLetter(0x33);
	}
	if(number == 4){
		writeLetter(0x34);
	}
	if(number == 5){
		writeLetter(0x35);
	}
	if(number == 6){
		writeLetter(0x36);
	}
	if(number == 7){
		writeLetter(0x37);
	}
	if(number == 8){
		writeLetter(0x38);
	}
	if(number == 9){
		writeLetter(0x39);
	}
}


void pulseToDisplay(int pulse)
{	//Writes pulsemessage and pulse on display
	pulseMessage(); //Writes pulsemessage "Din puls är:"
	int ten;
	int temp = pulse/100;
	if (temp > 0 ) {
		numberHandler(temp); //Writes the first number of pulse if it exists
		ten = pulse -100*temp;
	} else {
		ten = pulse;
	}
	temp = ten/10;
	numberHandler(temp); //Writes the first/(second) number of pulse
	temp = ten - temp*10;
	numberHandler(temp); //Writes the second/(third) number of pulse
}

void clear()
{
	//Clear display and return cursor to home
	EHigh();
	PORTA = _BV(PA0);
	ELow();
}

void writeReady() 
{
	//Prepare to write text
	PORTD = PORTD | _BV(PD7); //Sets E to 1
	PORTD = PORTD | _BV(PD5); //Sets RS to 1
}

void writeLetter(char letter)
{ 
	//Writes a letter
	writeReady();
	PORTA=letter;
	ELow();
}

void pulseMessage()
{
	//Writes text before pulsenumber: "Din puls är:"
	writeLetter(0x44); //D
	_delay_us(10);
	writeLetter(0x69); //i
	_delay_us(10);	
	writeLetter(0x6E); //n
	_delay_us(10);
	writeLetter(0x20); //
	_delay_us(10);
	writeLetter(0x70); //p
	_delay_us(10);
	writeLetter(0x75); //u
	_delay_us(10);
	writeLetter(0x6C); //l
	_delay_us(10);
	writeLetter(0x73); //s
	_delay_us(10);
	writeLetter(0x20); //
	_delay_us(10);
	writeLetter(0xE1); //ä
	_delay_us(10);
	writeLetter(0x72); //r
	_delay_us(10);
	writeLetter(0x3A); //:
	_delay_us(10);
}
void ELow()
{
	PORTD &= ~_BV(PD7); //Sets E to 0
}

void EHigh()
{
	PORTD = _BV(PD7); //Sets E to 1
}

void RSLow()
{
	PORTD &= ~_BV(PD5); //Sets RS to 0
}

void RSHigh()
{
	PORTD = _BV(PD5); //Sets RS to 1
}

void RWLow()
{
	PORTD &= ~_BV(PD6); //Sets RW to 0
}

void RWHigh()
{
	PORTD = _BV(PD6); //Sets RW to 1
}

void systemOn() 
{	//Installations for the system
	DDRA = 0xFF; //Sets all to outgoing
	DDRD = 0xE0; //Sets D5-D7 to outgoing
	DDRB = 0x10; //Sets B4 to outgoing
	DDRC &= DDRC | ~_BV(PC0); //Sets C0 to ingoing
	EHigh();
	PORTA = 0x38; //Function Set on
	ELow();
	EHigh();
	PORTA = 0x0F; //Cursor on
	ELow();
	sei(); //Enables interruptions
	timerReady();
	pulseCountReady();
	clear();
}

int main(void)
{
systemOn();

	while(1) {
		if(checkButton()==1) {
			clear(); //Clears display
			PORTB = PORTB | _BV(PB4); //Turns green LED on
			startTimer(); //Starts timer
			startCounter(); //Starts counter
		}
	}
}