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void irq_handler(registers_t regs) {
    if (regs.int_no >= 40) {
        outb(0xA0, 0x20);
    }
    outb(0x20, 0x20);
    
    if (__interrupt_handlers[regs.int_no] != 0) {
        __isr_t handler = __interrupt_handlers[regs.int_no];
        handler(regs);
    }
    
}

Code: Select all

uint32_t ticks = 0;

void __timer_init(uint32_t freq) {
    __register_interrupt_handler(IRQ0, &__timer_callback);
    uint32_t divisor = 1193180 / freq;

    outb(0x43, 0x36);
    
    uint8_t l = (uint8_t) (divisor & 0xFF);
    uint8_t h = (uint8_t) ((divisor >> 8) & 0xFF);

    outb(0x40, l);
    outb(0x40, h);
}


void __timer_callback(registers_t regs) {
    ticks++;
    printf("Tick\n");
}