//////////////////////////////////////////////////////
//ATtiny85 Activity_Counter &Frequency_meter programs;
// Time counting more than 255
// Mokhtar Zerdali 2022.
#include<avr/io.h>
#include<util/delay.h>
#include <TinyDebug.h>

#define F_CPU 8000000UL
#define INT_PIN PB2 // INT0 -> PB2 external interrupt pin
#define INT_PIN0 PB1

volatile unsigned long Overflowprb ; // value >256, and volatile between void programs
volatile unsigned long Overflowex ; // value >256, and volatile between void programs

volatile unsigned long Countprb;
volatile unsigned long Countex;

volatile unsigned long Time;
volatile unsigned long Start_Time;
volatile unsigned long Finish_Time;
volatile unsigned long Elapsed_Time;
volatile  float Frequency;
volatile  int PRB;// pulse rate beat
volatile boolean  i;
volatile byte  j;



void Global_setup()
{
  Debug.begin();
  //Debug.println(F("Hello, clock is running"));
  DDRB =  (1 << PB3) | (1 << PB4);
  TCCR0A = 0X00; //TCCR0A to low for normal port operation and mode 0.
  TCCR0B = 0X00; //WGM02=0
  TCNT0 = 0; //initializing the counter to 0
  TIMSK = bit (TOIE0); //|= (1 << TOIE0); //enabling overflow >255 interrupts of  timer0
  //Externall interrupts
  GIMSK |= (1 << INT0); // enable external interrupt
  GIMSK |= (1 << PCIE); // enable pin change
  PCMSK = bit(PCINT1); // pin PB1 as pin change
  sei(); //global interruption
  // i = digitalRead(PB0);
}
////////////////////////////////////////////
void Pulse_RB()
{
  Overflowprb = 0;
  TCCR0B |= (1 << CS00); //No prescaling clk
  // Mode sense of MCUCR Register to choose the adequate sense
  MCUCR = (1 << ISC01); //3/ FALLING mode sense
  //MCUCR = bit(ISC01) | bit(ISC00); //4// RISING mode sense
}
////////////////////////////////////////////
void External_counter()
{
  Overflowex = 0;  
  TCCR0B |= (1 << CS01) | (1 << CS02); //external counting, Clk on Falling edge sense
  /////////////////////////////////////Mode sense
  MCUCR &= ~(bit(ISC01) | bit(ISC00));    //1/ INT0 on low level, while ISR senses by mode low level
  // The low level of INT0 generates an interrupt request
}
///////////////////////////////
ISR (TIMER0_OVF_vect) //Interrupt vector for Timer0 >>>> Counter0
{
  i = digitalRead(PB1);
  if (i == HIGH)
  {
    Overflowprb++; // count number of overflow
  }
  else if (i == LOW)
  {
    Overflowex++; // count number of overflow
  }
} // End of TIMER0_OVF_vect

///////////////////Interruption Routine///////////////////////
ISR(INT0_vect) // Interrupter vector for external inerruption
{
    j= digitalRead(PB2);

  i = digitalRead(PB1);
  //digitalWrite(PB1, i);
  if (i == HIGH)
  {
    Countprb = TCNT0 + (Overflowprb << 8); //n° overflow*256
    Time = 0.000125 * Countprb; // 8MHz ; clk : 125 ns.
    Start_Time = Time;
    Debug.println("Frequency:");
    Debug.print(Frequency);
    Debug.println("Hz");
    Debug.println("###:");
    Debug.println("Pulse rate beat:");
    Debug.print(PRB);// heart
    Debug.println("/min");
    Debug.println("###:");
  }
  else if (i == LOW)
  {
    Countex = TCNT0 + (Overflowex << 8); //n° overflow*256
    Debug.println("Count:");
    Debug.print(Countex);
    Debug.println("");
    Debug.println("###:");
  }

}
///////////////end of interruption////////////////////////////////////////////////////
int main()
{
  Global_setup();
  i = digitalRead(PB1);
  if (i == HIGH)
  {
    Pulse_RB(); // pulse rate beat program

    while (1)
    {
      Countprb = TCNT0 + (Overflowprb << 8); //n° overflow*256
      Time = 0.000125 * Countprb; // 8MHz ; clk : 125 ns.
      Finish_Time = Time;
      Elapsed_Time = Finish_Time - Start_Time;
      Frequency = 1000 / float(Elapsed_Time); // on Hz
      PRB = 60 * Frequency; //pulse rate beat
      //if (Start_Time > 1500)
    }
  }
  else if (i == LOW)
  {

    External_counter(); // counting program
    while (1)
    {

    }
  }
}