#include <avr/io.h>
#include <avr/interrupt.h>
#include <math.h>
#include <stdlib.h>



typedef unsigned char  u08;
#define ADC_VREF_TYPE 0xA0

volatile u08 einer=0b1000000, zehner=0b1000000;
u08 count=0,count1=0;
u08 umschalt=0;
u08 i; 
int data;  
int dataADC;
int maximum;
int minimum;
 int x;

// Timer 0 overflow interrupt service routine
ISR(SIG_OVERFLOW0)
{
	if (umschalt==0) 
  {
    PORTB &= ~(1 << 3);		// Bit 3 in PORTB wird geloescht
		PORTB |= (1 << 4);  	// Bit 4 in PORTB wird gesetzt
		umschalt = 1;
		PORTA = zehner;
	}
	else
	{
    PORTB &= ~(1 << 4);		// Bit 4 in PORTB wird geloescht
		PORTB |= (1 << 3);  	// Bit 3 in PORTB wird gesetzt
		umschalt=0;
		PORTA = einer;                
	}
}

// of the AD conversion result ad wandler 10
u08 read_adc(u08 adc_input)
{ 
	ADMUX=adc_input|ADC_VREF_TYPE;
	dataADC=0x00;
	// Start the AD conversion-Mittelwert aus 4 Wandlungen
	for(i=0;i<4;i++)
	{
		ADCSR|=0x40;
		// Wait for the AD conversion to complete
		while ((ADCSR & 0x10)==0); //auf Abschluss der Konvertierung warten
		dataADC += (ADCW>>7);   //Wandlungsergebnisse aufaddieren
		ADCSR|=0x10;        //ADC deaktivieren
	}
	dataADC /= 4;       //Summe dur vier teilen 0 arithm. Mittelwert
	return dataADC;
}

void delay_loop( u08 dauer )
{
   u08 i, j, k;
		for (i=0; i<255; i++)   /* outer delay loop */
			for (j=0; j<255; j++)   /* outer delay loop */
				for(k=0; k<dauer;k++) /* inner delay loop */
					{}
}

u08 get_segment_minus(u08 in)
{ 
	switch(in)
	{
		case 1: return 0b01111001;
		case 2: return 0b00100100;
		case 3: return 0b00110000;
		case 4: return 0b00011001;
		case 5: return 0b00010010;
		case 6: return 0b00000010;
		case 7: return 0b01111000;
		case 8: return 0b00000000;
		case 9: return 0b00010000;
		case 0: return 0b01000000;
		default: return 0b01111001;
	}
}

u08 get_segment(u08 in)
{ 
	switch(in)
	{
		case 1: return 0b11111001;
		case 2: return 0b10100100;
		case 3: return 0b10110000;
		case 4: return 0b10011001;
		case 5: return 0b10010010;
		case 6: return 0b10000010;
		case 7: return 0b11111000;
		case 8: return 0b10000000;
		case 9: return 0b10010000;
		case 0: return 0b11000000;
		default: return 0b11111001;
	}
}
void Anzeige(int Wert)
{
	if(Wert<0)
	{
			Wert=abs(Wert);
			einer= get_segment_minus(Wert%10);
			zehner=get_segment_minus(Wert/10); 	
	}
		else
		{
			einer= get_segment(Wert%10);
			zehner=get_segment(Wert/10);
		}
}


 
void temperatur()

{
			// Place your code here
		data = read_adc(0x9a);
    data -=36;
	
	
	
	
	if(data>maximum)
	maximum=data;
	if(data<minimum)
	minimum=data;
	
}

// Declare your global variables here
int main(void)
{
	// Declare your local variables here
	
	// Input/Output Ports initialization
	// Port A initialization
	PORTA=0xFF;
	DDRA=0xFF;
	// Port B initialization
	PORTB=0x03;
	DDRB=0x18;
	// Timer/Counter 0 initialization
	// Clock source: System Clock
	// Clock value: 3,906 kHz
	TCCR0=0x03;
	TCNT0=0x00;
	PLLCSR=0x00;
	TCCR1A=0x00;
	TCCR1B=0x00;
	TCNT1=0x00;
	OCR1A=0x00;
	OCR1B=0x00;
	OCR1C=0x00;
	// External Interrupt(s) initialization
	// INT0: Off
	GIMSK=0x00;
	MCUCR=0x00;
	// Timer(s)/Counter(s) Interrupt(s) initialization
	TIMSK=0x02;
	// Universal Serial Interface initialization
	USICR=0x00; // Mode: Disabled
	
	// Analog Comparator initialization
	ACSR=0x8E;  // Analog Comparator: Off 
	
	// ADC initialization
	// ADC Clock frequency: 31,250 kHz
	// ADC Voltage Reference: Int., AREF discon.
	// Only the 8 most significant bits of
	// the AD conversion result are used
	ADMUX=ADC_VREF_TYPE;
	ADCSR=0x87;
	
	// Global enable interrupts
	sei();
	maximum=-37;
	minimum=100;
	while (1)
	{
		temperatur();
		if(!(PINB&(1<<PB0)))
		Anzeige(minimum);
		else if(!(PINB&(1<<PB1)))
	
		
		Anzeige(maximum);
		else
		Anzeige(data);
		delay_loop(20);
	}
	return 0;
}