src/kernel/sound/frequency.c


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#include <stdint.h>
#include <kernel/io/io.h>
#include <kernel/timer/timer.h>

void play_sound(uint32_t frequency)
{
    uint32_t divided;
    uint8_t tmp;

    divided = 1193180 / frequency;
    outb(0x43, 0xb6);
    outb(0x42, (uint8_t) (divided));
    outb(0x42, (uint8_t) (divided >> 8));

    tmp = inb(0x61);
    if (tmp != (tmp | 3)) {
        outb(0x61, tmp | 3);
    }
}

static void shut_up()
{
    uint8_t tmp = inb(0x61) & 0xFC;

    outb(0x61, tmp);
}

// Make a beep
void beep(uint32_t frequency, uint32_t ticks)
{
    play_sound(frequency);
    timer_wait(ticks);
    shut_up();
}