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int timer_ticks = 0;

void timer_phase(int hz)
{
    int divisor = 1193180 / hz;       /* Calculate our divisor */
    outportb(0x43, 0x36);             /* Set our command byte 0x36 */
    outportb(0x40, divisor & 0xFF);   /* Set low byte of divisor */
    outportb(0x40, divisor >> 8);     /* Set high byte of divisor */
}

void timer_handler(struct regs *r)
{
    timer_ticks++;

    /* Every 18 clocks (approximately 1 second), we will
    *  display a message on the screen */
    if (timer_ticks % 18 == 0) {
        writeOutput("One second has passed");
    } else {
    	writeOutput("not passed...");
    }
}

void timer_install()
{
    irq_install_handler(0, timer_handler);
}

void timer_wait(int ticks)
{
    unsigned long eticks;

    eticks = timer_ticks + ticks;
    while(timer_ticks < eticks);
}