[AVR] Atmega328P Timer Interrupt Problem

//This is the timer8.c source file
#include <avr/io.h>
#include "timer8.h"
#include <avr/interrupt.h>

#define TIMER_0_START_ADDRESS (0x0044)
#define TIMER_2_START_ADDRESS (0x00B0)

typedef volatile struct{ // this structure holds registers
    unsigned char tccra;
    unsigned char tccrb;
    unsigned char ocra;
    unsigned char ocrb;
}timer_hw;

struct timer{
    timer_hw volatile *p_hw;
};

static timer g_timer[2];
uint8_t temp_clock_type = 0x00;

void timer_init(void){
    g_timer[0].p_hw = (timer_hw volatile *)TIMER_0_START_ADDRESS;
    g_timer[1].p_hw = (timer_hw volatile *)TIMER_2_START_ADDRESS;
}

timer *timer_open(timer_type type){ // it return the related timer pointer
    timer *p_timer = &(g_timer[type]);
    return p_timer;
}

void timer_set(timer *timer_temp, timer_mode mode, timer_clock clock, uint8_t duration_ms){
// It sets the related timer modes and  thresould duration
    timer_hw volatile *p_hw = timer_temp->p_hw;
    temp_clock_type = clock;
    p_hw->tccra |= mode;
    p_hw->ocra = duration_ms;
    TIMSK0=(0<<OCIE0B) | (1<<OCIE0A) | (0<<TOIE0);
}

void timer_start(timer *timer_temp){
// It starts the timer 
    timer_hw volatile *p_hw = timer_temp->p_hw;
    p_hw->tccrb |= temp_clock_type;
}

void timer_stop(timer *timer_temp){
// it stops the timer
    timer_hw volatile *p_hw = timer_temp->p_hw;
    p_hw->tccrb = 0x00;
}

void timer_restart(timer *timer_temp){
    timer_hw volatile *p_hw = timer_temp->p_hw;
    p_hw->ocra = 0x00;
    p_hw->ocrb = 0x00;
}

void timer_clear(timer *timer_temp){
// it sets all related timer registers to zero 
    timer_hw volatile *p_hw = timer_temp->p_hw;
    p_hw->tccra = 0x00;
    p_hw->tccrb = 0x00;
    p_hw->ocra = 0x00;
    p_hw->ocrb = 0x00;
}


ISR(TIMER0_OVF_vect){ // when interrupt occurs, timer_callback function is called
    timer_callback();
}

// this is the header file for timer library
#ifndef TIMER_H_INCLUDED
#define TIMER_H_INCLUDED

typedef enum timer_type{
    TIMER_0,
    TIMER_2,
}timer_type;

typedef enum timer_mode{
    NORMAL_MODE,
    CTC_MODE,
    FAST_PWM_MODE,
    PHASE_CORRECT_PWM_MODE
}timer_mode;

//WGM0[2:0] 101 and 111 modules are not supported

typedef enum timer_clock{
    CLOCK_1,
    CLOCK_8,
    CLOCK_64,
    CLOCK_256,
    CLOCK_1024,
    CLOCK_EXT_FALLING_EDGE,
    CLOCK_EXT_RISING_EDGE
}timer_clock;

typedef struct timer timer;

void timer_init(void);
timer *timer_open(timer_type);
void timer_set(timer *, timer_mode, timer_clock, uint8_t);
void timer_start(timer *);
void timer_stop(timer *);
void timer_restart(timer *);
void timer_clear(timer *);
void timer_callback();


#endif // TIMER_H_INCLUDED

/*
This is the main function 
 */

#include <avr/io.h>
#include <timer8.h>
#include <gpio.h>

void timer_callback();

int main(void)
{

    // Insert code
    gpio_init(); //initialize the gpio library and gpio library is used for manipulating the ports
    gpio *Port_B = gpio_open(PIN_B);
    gpio_port_direction_set(Port_B,0xFF); // Set the All PORTB as an output
    timer_init(); // initialize the timer library
    timer *Timer_0 = timer_open(TIMER_0);
    timer_set(Timer_0,NORMAL_MODE,CLOCK_1,200); // Set the timer registers
    timer_start(Timer_0); // starts the timer
    while(1)
    ;

    return 0;
}

void timer_callback(){
    PORTB ^= 0xFF;
}

sei()

sei()