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#include <string.h>
#include "common.h"
#include "gba-buttons.c"
#include "background-tiles.c"
#include "sprites.h"
#include "text.h"
//
// Main functions.
//
// TODO: Cleanup OBJ/OAM memory copying and access.
//
//
// BIOS calls
//
int hblank_counter = 0;
void
irs_hblank_func() {
hblank_counter++;
if (DISP_VCOUNT >= 160) {
PAL_BUFFER_BG[0] = rgb15(0, 0, 0);
} else {
u16 clr = (DISP_VCOUNT / 8);
PAL_BUFFER_BG[0] = rgb15(clr, 0, 31 - clr);
}
}
int main(void) {
// Configure the display in mode 0 to show OBJs, where tile memory is
// sequential.
DISP_CTRL = DISP_ENABLE_SPRITES | DISP_MODE_0 | DISP_BG_0;
// Initialize sprite button overlay.
init_sprite_pal(0, COLOR_WHITE);
init_sprites(0);
init_button_sprites();
// Initialize text engine.
txt_init(0, COLOR_RED, 0);
// Register interrupts.
irq_init();
irs_set(IRQ_VBLANK, irs_stub);
irs_set(IRQ_HBLANK, irs_hblank_func);
// turn sound on
SOUND_STATUS = SOUND_ENABLE;
SOUND_DMG_MASTER = sound_volume(SOUND_SQUARE1 | SOUND_SQUARE2, 7);
SOUND_DSOUND_MASTER = SOUND_DMG100;
char *note_names[] = {
"C" , "C#" , "D" , "D#" ,
"E" , "F" , "F#" , "G" ,
"G#" , "A" , "A#" , "B"
};
int frame_counter = 0;
Note active_note = NOTE_C;
u8 octave = 0;
bool playing = false;
bool new_note = false;
u8 interval = 1;
while(true) {
bios_vblank_wait();
poll_keys();
txt_position(0, 1);
txt_clear_line();
if (key_pressed(KEY_B)) {
active_note = NOTE_C;
new_note = true;
octave = 0;
} else if (key_pressed(KEY_A)) {
active_note = NOTE_D;
new_note = true;
octave = 0;
} else if (key_pressed(KEY_LEFT)) {
active_note = NOTE_E;
new_note = true;
octave = 0;
} else if (key_pressed(KEY_DOWN)) {
active_note = NOTE_F;
new_note = true;
octave = 0;
} else if (key_pressed(KEY_RIGHT)) {
active_note = NOTE_G;
new_note = true;
octave = 0;
} else if (key_pressed(KEY_UP)) {
active_note = NOTE_A;
new_note = true;
octave = 0;
} else if (key_pressed(KEY_L)) {
active_note = NOTE_B;
new_note = true;
octave = 0;
} else if (key_pressed(KEY_R)) {
active_note = NOTE_C;
new_note = true;
octave = 1;
}
if (key_pressed(KEY_START)) {
interval++;
}
if (key_pressed(KEY_SELECT)) {
interval--;
}
if (key_curr > 0) {
txt_printf(" Playing: %s + %s\n",
note_names[active_note],
(note_names[(active_note + interval) % 12]));
playing = true;
} else {
playing = false;
}
if (playing) {
if (new_note) {
SOUND_SQUARE1_CTRL = SOUND_SQUARE_ENV_VOL(4) | SOUND_SQUARE_ENV_TIME(0);
SOUND_SQUARE2_CTRL = SOUND_SQUARE_ENV_VOL(4) | SOUND_SQUARE_ENV_TIME(0);
SOUND_SQUARE1_FREQ = SOUND_SQUARE_RESET | sound_rate(active_note, octave);
SOUND_SQUARE2_FREQ = SOUND_SQUARE_RESET | sound_rate((active_note + interval) % 12, octave);
}
new_note = false;
} else {
SOUND_SQUARE1_CTRL = SOUND_SQUARE_ENV_VOL(0) | SOUND_SQUARE_ENV_TIME(0);
SOUND_SQUARE2_CTRL = SOUND_SQUARE_ENV_VOL(0) | SOUND_SQUARE_ENV_TIME(0);
SOUND_SQUARE1_FREQ = 0;
SOUND_SQUARE2_FREQ = 0;
}
frame_counter++;
update_button_sprites();
};
return 0;
}
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