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

// Input: Square wave on ICP PIN
// This program determines the pulse width of a square wave and represents that pulse width
//in a certain form in port D

double overflow_counter, rising_edge, falling_edge, pulse_width;
double TOP = 65535;

//This interrupt service routine calculates the pulse width of a square wave on the ICP pin
//and displays that in a certain form on PORT D

ISR(TIMER1_CAPT_vect){
    
    if (PORTA == 0xAA) PORTA = 0x55;
    else PORTA == 0xAA;

    // If ICP pin is set, there was a rising edge else if its low there must have been a falling edge /
    if (bit_is_set(PINB,1)){
        rising_edge = ICR1;
        TCCR1B &= ~(1<<ICES1); //Capture now on falling edge
        overflow_counter = 0;
    }
    else{
        falling_edge = ICR1;
        TCCR1B |= (1<<ICES1);//Capture now on rising edge
        pulse_width =falling_edge - rising_edge + TOP*overflow_counter;

        //Test to see if correct pulse width being calculated
        //if pulse width is greater than 35 than PD2 goes high otherwise PD3 IS HIGH
        if (pulse_width>35){
            PORTD |= (1<<PD2);
            PORTD &= ~(1<<PD3);
        }
        else{
            PORTD |= (1<<PD3);
            PORTD &= ~(1<<PD2);
        }
    }
}


ISR(TIMER1_OVF_vect){
    overflow_counter++; //increment counter when overflow occurs
}


int main(void){

    DDRB = 0;// ICP pin as input which is pin 0 on port B/

    DDRD = 0XFF; // ALL PINS on port D are set as output.

    DDRA = 0xFF;
    PORTA = 0xAA;


    sei();//enable global interrupt

    //setting up Timer control register 1

    //TOP VALUE IS 0XFFFF; (NORMAL MODE)
    TCCR1A = 0;
    TCCR1B = 0;


    //SETS PRESCALER ON 1
    TCCR1B |= (1<<CS10);
    TCCR1B &= ~(1<<CS11) & ~(1<<CS12);

    // Enable Input noise canceller and capture time on rising edge
    TCCR1B |= (1<<ICES1) | (1<<ICNC1);

    TIMSK = 0;
    TIMSK |= (1<<TICIE1); //Enable Input Capture Interrupt
    TIMSK |= (1<<TOIE1); //Enable timer overflow interrupt

    while(1){}

}

static u16    long_time;
u32 impulse_len;

void ic_init(void)
{
    TCCR1A = 0;
    TCCR1B |= _BV(ICNC1) | _BV(CS10) | _BV(ICES1);;
    TIMSK |= _BV(TICIE1) | _BV(TOIE1);
    TIFR = _BV(ICF1) | _BV(TOV1);
}

SIGNAL(SIG_OVERFLOW1)
{
    long_time++;
}

SIGNAL(SIG_INPUT_CAPTURE1)
{
    static u32 prev_ticks = 0;    
    u16 icr = ICR1;
    u32 ticks;

    LoWord(ticks) = icr;
    HiWord(ticks) = long_time;

    if ((ticks < prev_ticks) && HiWord(ticks))
        HiWord(ticks)++;

    impulse_len = ticks - prev_ticks;
    prev_ticks = ticks;
}

volatile uint16_t long_time;
volatile uint32_t pulse_time;
volatile uint32_t pause_time;
volatile uint8_t flag = 0;

void ic_init(void)
{
TCCR1A = 0;
TCCR1B |= (1<<ICNC1)|(1<<ICES1)|(1<<CS10); // здесь, возможно, нужно выбрать другой prescaler
TIMSK |= (1<<TICIE1)|(1<<TOIE1);
TIFR = (1<<ICF1)|(1<<TOV1);
asm("sei");
}

SIGNAL(SIG_OVERFLOW1)
{
long_time++;
if(long_time==0)
{
// overflow detected! Обработка переполнения (если нужно)
}
}

SIGNAL(SIG_INPUT_CAPTURE1)
{
uint16_t ticks;

TCNT1=0;
ticks = ICR1;
long_time = 0;

if(TCCR1B & (1<<ICES1))
{ //rising edge detected
pause_time = long_time;
pause_time = (pause_time<<16) | ticks;
TCCR1B &= ~(1<<ICES1); // switch to detect falling edge
}
else
{ //falling edge detected
pulse_time = long_time;
pulse_time = (pulse_time<<16) | ticks;
TCCR1B |= 1<<ICES1; // switch to detect rising edge
}
flag = 1; // new data arrived
}

void main_loop( void ){

while(1)
{
if(flag)
{
// Здесь обрабатываем поступившие данные
flag=0;
}
}
}

    DDRB = 0;// ICP pin as input which is pin 0 on port B/
    sei();//enable global interrupt

    //setting up Timer control register 1

    //TOP VALUE IS 0XFFFF; (NORMAL MODE)
    TCCR1A = 0;
    TCCR1B = 0;
    //SETS PRESCALER ON 1
    TCCR1B |= (1<<CS10);
    TCCR1B &= ~(1<<CS11) & ~(1<<CS12);
    // Enable Input noise canceller and capture time on rising edge
    TCCR1B |= (1<<ICES1)| (1<<ICNC1); //| (1<<ICNC1)

    TIMSK = 0;
    TIMSK |= (1<<TICIE1); //Enable Input Capture Interrupt
    TIMSK |= (1<<TOIE1); //Enable timer overflow interrupt
    TIFR = _BV(ICF1) | _BV(TOV1);