#define RED_LED 12
#define Button_Pin 7
unsigned int counter10msec=0;/*Counter for 10 milli seconds*/
/*unsigned char LED_STATE=0;*/
//unsigned int counter100msec=0;/*Counter for 100 millisecond*/

void setup() {
  Serial.begin(115200);
   Digitalpin();
   Timer();
  }

void loop()
{
  if(counter10msec>=(10))
  {
    counter10msec=0;
    Task_10ms();
  }
  else{
    /*Do Nothing*/
  }
}

/*With the settings above, this IRS will trigger each count */

ISR(TIMER0_COMPA_vect){
  TCNT0  = 0; /*First, set the timer back to 0 so it resets for next interrupt*/
  counter10msec++;  
  //counter100msec++;  
}

void Digitalpin(void)
{
  pinMode(RED_LED, OUTPUT);
  pinMode(Button_Pin, INPUT);  
}
void Timer(void)
{
  cli();                      /*stop interrupts for till we make the settings*/
  /*1. First we reset the control register to amke sure we start with everything disabled.*/
  TCCR0A = 0;                 /* Reset entire TCCR1A to 0 */
  TCCR0B = 0;                 /* Reset entire TCCR1B to 0 */
  /*2. We set the prescalar to the desired value by changing the CS10 CS12 and CS12 bits. */  

  TCCR0B |= B00000011;        /* Set CS10 and CS11 to 1 so we get prescalar 64  */
  /*3. We enable compare match mode on register A*/

  TIMSK0 |= B00000010;        /*Set OCIE1A to 1 so we enable compare match A */
  /*4. Set the value of register A to 31250*/

  OCR0A = 250;             /*Finally we set compare register A to this value*/  
  sei();                     /*Enable back the interrupts*/
}

/* Function For 10 ms Delay*/

void Task_10ms(void)
{
  Read_Button();
}

void Read_Button(void)
{
  unsigned char Button_State = digitalRead(Button_Pin);/*monitor the button state*/
  if (Button_State==HIGH)
  {
     Task_100ms();
  }
  else
  {
    LED_OFF();
  }
}

/* Function For 100 ms Delay*/

void Task_100ms(void)
{
 LED_ON();
}

void LED_ON()
{
  
  digitalWrite(RED_LED,HIGH);
  
}

void LED_OFF(void)
{
  digitalWrite(RED_LED,LOW);
}