//7 segment display from 0-f

/* Example code with timer interrupt that will create an interruption each 
 *  1ms using timer1 and prescalar of 64.
Calculations (for 1ms): 
  System clock 16 Mhz and Prescalar 64;
  Timer 1 speed = 16Mhz/64 = 250 Khz    
  Pulse time = 1/250 Khz =  4us  
  Count up to = 1ms / 4us = 250 (so this is the value the OCR register should have)*/  
#define LED_BLUE 13
#define LED_RED 12
#define LED_GREEN 11


unsigned char LED_STATE_10ms = HIGH;
unsigned char LED_STATE_40ms = HIGH;
unsigned char LED_STATE_100ms = HIGH;
unsigned char COUNT_10ms=0;
unsigned char COUNT_40ms=0;
unsigned char COUNT_100ms=0;
void Task_10ms();
void Task_40ms();
void Task_100ms();
void Timer_init();
void digitalpin_init();
void count();
unsigned char num=0;
unsigned char counter=0;


unsigned char display_digit_array[] = {~0x3F,~0x6,~0x5B,~0x4F ,~0x66, ~0x6D,~0x7D,~0x7,~0x7F,~0x6F,0x8,0x00,0x46,~0x3F,0x06,0x0E}  ; 



void setup()
 {
  digitalpin_init();
  Timer_init(); //Set the pin to be OUTPUT
 }

void loop() {
  // put your main code here, to run repeatedly:
  if(COUNT_10ms >= 10)
  { 
    COUNT_10ms = 0;
    Task_10ms();
   }
  if(COUNT_40ms >= 40)
  { 
    COUNT_40ms = 0;
    Task_40ms();
   }
  if(COUNT_100ms >= 100)
  { 
    COUNT_100ms = 0;
    Task_100ms();
   }
 
 
}

//With the settings above, this IRS will trigger each 500ms.
ISR(TIMER1_COMPA_vect)
{
  
  TCNT1  = 0;                  //First, set the timer back to 0 so it resets for next interrupt
  //Increment count
  COUNT_10ms++;
  COUNT_40ms++;
  COUNT_100ms++;
}

void digitalpin_init()
{ 
 pinMode(2,OUTPUT);
 pinMode(3,OUTPUT);
 pinMode(4,OUTPUT);
 pinMode(5,OUTPUT);
 pinMode(6,OUTPUT);
 pinMode(7,OUTPUT);
 pinMode(8,OUTPUT);
}
void Timer_init()
{
   cli();                      //stop interrupts for till we make the settings
  /*1. First we reset the control register to amke sure we start with everything disabled.*/
  TCCR1A = 0;                 // Reset entire TCCR1A to 0 
  TCCR1B = 0;                 // Reset entire TCCR1B to 0
 
  /*2. We set the prescalar to the desired value by changing the CS10 CS12 and CS12 bits. */  
  TCCR1B |= B00000011;        //Set CS12 to 1 so we get prescalar 64 
  
  /*3. We enable compare match mode on register A*/
  TIMSK1 |= B00000010;        //Set OCIE1A to 1 so we enable compare match A 
  
  /*4. Set the value of register A to 31250*/
  OCR1A = 250;             //Finally we set compare register A to this value  
  sei();                     //Enable back the interrupts
}

void Task_10ms()
{
 LED_STATE_10ms = !LED_STATE_10ms;      
  digitalWrite(LED_BLUE,LED_STATE_10ms);  
  
}


void Task_40ms()
{
  
    LED_STATE_40ms = !LED_STATE_40ms;      
    digitalWrite(LED_RED,LED_STATE_40ms);  
  
}
void Task_100ms()
{
  
    display_on(display_digit_array[num]);
    count();

}

void display_on(byte num) // This function turns on the correct pins to display numbers passed to it // through the variable “num”.
{
  for(int i=0;i<7;i++)
  {
    unsigned char result = bitRead(num, i);
    if (result == 1) // Check to see if this segment should be on.
    {
       digitalWrite(i+2, HIGH);
     } // Turns on the segment.
   else // Otherwise, it turns it off.
     {
        digitalWrite(i+2, LOW);
      }

  }
}


void count()
{
  
  if(counter>=10 )
  {
    counter=0;
    num=num+1;
    if(num>15)
    {
      num=0;
    }
  }
  else
  {
    counter++;
  }
}