// avrdude -pt13 -cusbtiny -Pusb -e -U lfuse:w:0x7a:m -U hfuse:w:0xfb:m -U flash:w:C:\attiny13_timer.cpp.hex.txt:i

//                       +-\/-+
//      A0   (D5)  PB5  1|    |8   VCC
//      A3   (D3)  PB3  2| AT |7   PB2  (D2)  INT0  A1
//      A2   (D4)  PB4  3| 13 |6   PB1  (D1)        pwm1
//                 GND  4|    |5   PB0  (D0)        pwm0
//                       +----+


#define F_CPU 9600000 // clock 9.6 MHz
#include <avr/io.h>
#include <util/delay.h>

long interval, delka_pulsu, delka_pauzy;
unsigned long previousMillis;
byte  pulse, wait;


void setup() {

  OSCCAL = 88; // kalibracni konstanta oscilatoru - jen buh zna tu spravnou
  pinMode(1, INPUT); 
  pinMode(0, OUTPUT); 
  digitalWrite(0,LOW);
  volatile const int8_t adc2 = (1<<ADLAR)  | 2; 
  volatile const int8_t adc3 = (1<<ADLAR)  | 3; 

  _delay_ms(500); // startovaci pauza

  ADMUX |= (1 << REFS0); // interni reference
  ADCSRA |= (1 << ADPS2) | (1 << ADPS1) | (1 << ADPS0) | (1 << ADEN); // frekvence ADC = 75KHz pro 9.6MHz oscilator

  // cteni AD2
  ADMUX = adc2;
  ADCSRA |= (1 << ADSC);
  while (ADCSRA & (1 << ADSC));
  pulse = ADCH; // delka pulsu 0-255

  // cteni AD3
  ADMUX = adc3;
  ADCSRA |= (1 << ADSC);
  while (ADCSRA & (1 << ADSC));
  wait = ADCH; // pauza mezi pulsy 0-255

  unsigned long previousMillis=0;
  delka_pulsu = (long)pulse * 1000; // prepocet na milisekundy = 0-255 sekund
  delka_pauzy = (long)(wait) * 60000; // prepocet na milisekundy = 0-255 minut

  if ((pulse == 0) or (wait == 0)) { // osetreni nulovych hodnot v nastaveni
    while (1) { // nedelej nic do nekonecna
    }
  }

  // revers + pocatecni stav
  if (digitalRead(1) == HIGH) {
    interval = delka_pulsu; // cyklus zacina pulsem 0-255 sekund
    digitalWrite(0,HIGH); // puls = HIGH
  } 
  else {   
    interval = delka_pauzy; // cyklus zacina pauzou 0-255 minut
    digitalWrite(0,LOW); // pauza = LOW
  }
}


void loop() { // nekonecna smycka

  unsigned long currentMillis = millis(); // cteni millis()
  if ((unsigned long)(currentMillis - previousMillis) >= interval) {
    digitalWrite(0, !digitalRead(0)); // zmena signalu na pinu 0
    previousMillis = currentMillis;

    if ( interval == delka_pulsu) {  // zmena intervalu puls/pauza
      interval = delka_pauzy;  // 0-255 minut
    } 
    else { 
      interval = delka_pulsu; // 0-255 sekund
    }
  }
  _delay_ms(200); // cely cyklus bezi v intervalu 200ms
}