Add fixed rates for all notes in the sound range

From C2 to C8

2 files changed, 64 insertions, 72 deletions

diff --git a/src/common.h b/src/common.h
index 7a0c50c..e864a71 100644
--- a/src/common.h
+++ b/src/common.h
@@ -601,29 +601,46 @@ sound_volume(SoundChannel channels, u8 volume) {
 #define SOUND_SQUARE_RESET (1 << 0xF)
 
 typedef enum {
-    NOTE_C,
-    NOTE_C_SHARP,
-    NOTE_D,
-    NOTE_D_SHARP,
-    NOTE_E,
-    NOTE_F,
-    NOTE_F_SHARP,
-    NOTE_G,
-    NOTE_G_SHARP,
-    NOTE_A,
-    NOTE_A_SHARP,
-    NOTE_B,
+    NOTE_C_2       , NOTE_C_SHARP_2 , NOTE_D_2       , NOTE_D_SHARP_2 ,
+    NOTE_E_2       , NOTE_F_2       , NOTE_F_SHARP_2 , NOTE_G_2       ,
+    NOTE_G_SHARP_2 , NOTE_A_2       , NOTE_A_SHARP_2 , NOTE_B_2       ,
+    NOTE_C_3       , NOTE_C_SHARP_3 , NOTE_D_3       , NOTE_D_SHARP_3 ,
+    NOTE_E_3       , NOTE_F_3       , NOTE_F_SHARP_3 , NOTE_G_3       ,
+    NOTE_G_SHARP_3 , NOTE_A_3       , NOTE_A_SHARP_3 , NOTE_B_3       ,
+    NOTE_C_4       , NOTE_C_SHARP_4 , NOTE_D_4       , NOTE_D_SHARP_4 ,
+    NOTE_E_4       , NOTE_F_4       , NOTE_F_SHARP_4 , NOTE_G_4       ,
+    NOTE_G_SHARP_4 , NOTE_A_4       , NOTE_A_SHARP_4 , NOTE_B_4       ,
+    NOTE_C_5       , NOTE_C_SHARP_5 , NOTE_D_5       , NOTE_D_SHARP_5 ,
+    NOTE_E_5       , NOTE_F_5       , NOTE_F_SHARP_5 , NOTE_G_5       ,
+    NOTE_G_SHARP_5 , NOTE_A_5       , NOTE_A_SHARP_5 , NOTE_B_5       ,
+    NOTE_C_6       , NOTE_C_SHARP_6 , NOTE_D_6       , NOTE_D_SHARP_6 ,
+    NOTE_E_6       , NOTE_F_6       , NOTE_F_SHARP_6 , NOTE_G_6       ,
+    NOTE_G_SHARP_6 , NOTE_A_6       , NOTE_A_SHARP_6 , NOTE_B_6       ,
+    NOTE_C_7       , NOTE_C_SHARP_7 , NOTE_D_7       , NOTE_D_SHARP_7 ,
+    NOTE_E_7       , NOTE_F_7       , NOTE_F_SHARP_7 , NOTE_G_7       ,
+    NOTE_G_SHARP_7 , NOTE_A_7       , NOTE_A_SHARP_7 , NOTE_B_7       ,
+    NOTE_C_8
 } Note;
 
-u32
-sound_rate(Note note, u32 octave) {
-    const u32 base_rate[12] = {
-        8013, 7566, 7144, 6742, // C , C#, D , D#
-        6362, 6005, 5666, 5346, // E , F , F#, G
-        5048, 4766, 4499, 4246  // G#, A , A#, B
-    };
-    return 2048 - (base_rate[note] >> (4 + octave));
-}
+static char * note_names[] =  {
+    "C2", "C#2", "D2", "D#2", "E2", "F2", "F#2", "G2", "G#2", "A2", "A#2", "B2",
+    "C3", "C#3", "D3", "D#3", "E3", "F3", "F#3", "G3", "G#3", "A3", "A#3", "B3",
+    "C4", "C#4", "D4", "D#4", "E4", "F4", "F#4", "G4", "G#4", "A4", "A#4", "B4",
+    "C5", "C#5", "D5", "D#5", "E5", "F5", "F#5", "G5", "G#5", "A5", "A#5", "B5",
+    "C6", "C#6", "D6", "D#6", "E6", "F6", "F#6", "G6", "G#6", "A6", "A#6", "B6",
+    "C7", "C#7", "D7", "D#7", "E7", "F7", "F#7", "G7", "G#7", "A7", "A#7", "B7",
+    "C8"
+};
+
+const u32 sound_rates[] = {
+    44  , 156 , 262 , 363 , 457 , 547 , 631 , 710 , 785 , 856 , 923 , 986 ,
+    1046, 1102, 1155, 1205, 1252, 1297, 1339, 1379, 1416, 1452, 1485, 1517,
+    1547, 1575, 1601, 1626, 1650, 1672, 1693, 1713, 1732, 1750, 1766, 1782,
+    1797, 1811, 1824, 1837, 1849, 1860, 1870, 1880, 1890, 1899, 1907, 1915,
+    1922, 1929, 1936, 1942, 1948, 1954, 1959, 1964, 1969, 1973, 1977, 1981,
+    1985, 1988, 1992, 1995, 1998, 2001, 2003, 2006, 2008, 2010, 2012, 2014,
+    2016,
+};
 
 //
 // Misc.
@@ -638,4 +655,9 @@ wait_vsync(void) {
     while(DISP_VCOUNT < 160);
 }
 
+// General utility functions. Min/Max/Clamp
+#define MIN(A, B) ((A) <= (B) ? (A) : (B))
+#define MAX(A, B) ((A) >= (B) ? (A) : (B))
+#define CLAMP(X, MIN, MAX) ((X) <= (MIN) ? (MIN) : (X) > (MAX) ? (MAX): (X))
+
 #endif // GBAEXP_COMMON_H
diff --git a/src/main.c b/src/main.c
index 30452e1..8b36226 100644
--- a/src/main.c
+++ b/src/main.c
@@ -13,23 +13,6 @@
 // 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.
@@ -46,24 +29,18 @@ int main(void) {
     // 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;
+    Note active_note = NOTE_C_4;
+    int octave_diff = 0;
     bool playing = false;
     bool new_note = false;
-    u8 interval = 1;
+    u8 interval = 4;
     while(true) {
         bios_vblank_wait();
         poll_keys();
@@ -72,49 +49,39 @@ int main(void) {
         txt_clear_line();
 
         if (key_pressed(KEY_B)) {
-            active_note = NOTE_C;
+            active_note = NOTE_C_4 + 12 * octave_diff;
             new_note = true;
-            octave = 0;
         } else if (key_pressed(KEY_A)) {
-            active_note = NOTE_D;
+            active_note = NOTE_D_4 + 12 * octave_diff;
             new_note = true;
-            octave = 0;
         } else if (key_pressed(KEY_LEFT)) {
-            active_note = NOTE_E;
+            active_note = NOTE_E_4 + 12 * octave_diff;
             new_note = true;
-            octave = 0;
         } else if (key_pressed(KEY_DOWN)) {
-            active_note = NOTE_F;
+            active_note = NOTE_F_4 + 12 * octave_diff;
             new_note = true;
-            octave = 0;
         } else if (key_pressed(KEY_RIGHT)) {
-            active_note = NOTE_G;
+            active_note = NOTE_G_4 + 12 * octave_diff;
             new_note = true;
-            octave = 0;
         } else if (key_pressed(KEY_UP)) {
-            active_note = NOTE_A;
+            active_note = NOTE_A_4 + 12 * octave_diff;
             new_note = true;
-            octave = 0;
         } else if (key_pressed(KEY_L)) {
-            active_note = NOTE_B;
+            active_note = NOTE_B_4 + 12 * octave_diff;
             new_note = true;
-            octave = 0;
         } else if (key_pressed(KEY_R)) {
-            active_note = NOTE_C;
+            active_note = NOTE_C_5 + 12 * octave_diff;
             new_note = true;
-            octave = 1;
         }
         if (key_pressed(KEY_START)) {
-            interval++;
+            octave_diff = CLAMP(octave_diff + 1, -2, 3);
         }
         if (key_pressed(KEY_SELECT)) {
-            interval--;
+            octave_diff = CLAMP(octave_diff - 1, -2, 3);
         }
 
         if (key_curr > 0) {
-            txt_printf(" Playing: %s + %s\n",
-                    note_names[active_note],
-                    (note_names[(active_note + interval) % 12]));
+            txt_printf(" Playing: %s\n", note_names[active_note]);
             playing = true;
         } else {
             playing = false;
@@ -122,10 +89,13 @@ int main(void) {
 
         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);
+                // SOUND_SQUARE1_SWEEP = 3 | (1 << 3) | (2 << 4);
+                // SOUND_SQUARE1_CTRL = SOUND_SQUARE_ENV_VOL(15) | SOUND_SQUARE_ENV_TIME(0x7);
+                // SOUND_SQUARE2_CTRL = SOUND_SQUARE_ENV_VOL(15) | SOUND_SQUARE_ENV_TIME(0);
+                SOUND_SQUARE1_CTRL = SOUND_SQUARE_ENV_VOL(15) | SOUND_SQUARE_ENV_TIME(4) | SOUND_SQUARE_ENV_INC | SOUND_SQUARE_DUTY(3);
+                // SOUND_SQUARE2_CTRL = SOUND_SQUARE_ENV_VOL(15) | SOUND_SQUARE_ENV_TIME(4) | SOUND_SQUARE_ENV_INC;
+                SOUND_SQUARE1_FREQ = SOUND_SQUARE_RESET | sound_rates[active_note];
+                // SOUND_SQUARE2_FREQ = SOUND_SQUARE_RESET | sound_rate((active_note + interval) % 12, octave);
             }
             new_note = false;
         } else {