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#include "lib/klib.h"
#include <comus/asm.h>
#include <comus/drivers/pit.h>
#include <comus/drivers/spkr.h>
#include <lib.h>
#define CMD 0x43
#define SPKR 0x61
#define BASE 1193180
volatile uint64_t ticks = 0;
uint32_t pit_read_freq(uint8_t chan)
{
uint16_t div = 0;
cli();
outb(CMD, 0x36); // clear bits
div = inb(chan); // low byte
div |= inb(chan) << 8; // highbyte
sti();
return div * BASE;
}
void pit_set_freq(uint8_t chan, uint32_t hz)
{
uint16_t div = BASE / hz;
cli();
outb(CMD, 0x36);
outb(chan, div & 0xFF); // low byte
outb(chan, (div & 0xFF00) >> 8); // high byte
sti();
}
void spkr_play_tone(uint32_t hz)
{
uint8_t reg;
if (hz == 0) {
spkr_quiet();
return;
}
// set spkr freq
pit_set_freq(CHAN_SPKR, hz);
// enable spkr gate
reg = inb(SPKR);
if (reg != (reg | 0x3))
outb(SPKR, reg | 0x3);
}
void spkr_quiet(void)
{
uint8_t reg;
reg = inb(SPKR) & 0xFC;
outb(SPKR, reg);
}
void spkr_beep(void)
{
spkr_play_tone(1000);
kspin_milliseconds(100);
spkr_quiet();
}
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