From 73853d651a15ab4c0a800b36c91475ade6534b4e Mon Sep 17 00:00:00 2001
From: Jack Humbert <jack.humb@gmail.com>
Date: Fri, 31 May 2019 17:46:18 -0400
Subject: [PATCH] 5 voices at 44.1khz

---
 quantum/audio/audio_arm.c | 113 ++++++++++++++++++++++++++------------
 1 file changed, 77 insertions(+), 36 deletions(-)

diff --git a/quantum/audio/audio_arm.c b/quantum/audio/audio_arm.c
index e349a0758c..05920df702 100644
--- a/quantum/audio/audio_arm.c
+++ b/quantum/audio/audio_arm.c
@@ -77,12 +77,12 @@ bool glissando = true;
 #endif
 float startup_song[][2] = STARTUP_SONG;
 
-#define DAC_BUFFER_SIZE 100U
+#define DAC_BUFFER_SIZE 256U
 #ifndef DAC_SAMPLE_MAX
 #define DAC_SAMPLE_MAX  4095U
 #endif
 
-#define DAC_SAMPLE_RATE 30000U
+#define DAC_SAMPLE_RATE 44100U
 
 GPTConfig gpt7cfg1 = {
   .frequency    = DAC_SAMPLE_RATE,
@@ -96,52 +96,93 @@ static const dacsample_t dac_buffer[DAC_BUFFER_SIZE] = {
   // [0                 ... DAC_BUFFER_SIZE/2-1] = DAC_SAMPLE_MAX,
   // [DAC_BUFFER_SIZE/2 ... DAC_BUFFER_SIZE  -1] = 0,
 
-  // max 4095
-  0x800,0x880,0x900,0x97f,0x9fd,0xa78,0xaf1,0xb67,
-  0xbda,0xc49,0xcb3,0xd19,0xd79,0xdd4,0xe29,0xe78,
-  0xec0,0xf02,0xf3c,0xf6f,0xf9b,0xfbf,0xfdb,0xfef,
-  0xffb,0xfff,0xffb,0xfef,0xfdb,0xfbf,0xf9b,0xf6f,
-  0xf3c,0xf02,0xec0,0xe78,0xe29,0xdd4,0xd79,0xd19,
-  0xcb3,0xc49,0xbda,0xb67,0xaf1,0xa78,0x9fd,0x97f,
-  0x900,0x880,0x800,0x77f,0x6ff,0x680,0x602,0x587,
-  0x50e,0x498,0x425,0x3b6,0x34c,0x2e6,0x286,0x22b,
-  0x1d6,0x187,0x13f,0xfd,0xc3,0x90,0x64,0x40,
-  0x24,0x10,0x4,0x0,0x4,0x10,0x24,0x40,
-  0x64,0x90,0xc3,0xfd,0x13f,0x187,0x1d6,0x22b,
-  0x286,0x2e6,0x34c,0x3b6,0x425,0x498,0x50e,0x587,
-  0x602,0x680,0x6ff,0x77f
+  // 100 values, max 4095
+  // 0x800,0x880,0x900,0x97f,0x9fd,0xa78,0xaf1,0xb67,
+  // 0xbda,0xc49,0xcb3,0xd19,0xd79,0xdd4,0xe29,0xe78,
+  // 0xec0,0xf02,0xf3c,0xf6f,0xf9b,0xfbf,0xfdb,0xfef,
+  // 0xffb,0xfff,0xffb,0xfef,0xfdb,0xfbf,0xf9b,0xf6f,
+  // 0xf3c,0xf02,0xec0,0xe78,0xe29,0xdd4,0xd79,0xd19,
+  // 0xcb3,0xc49,0xbda,0xb67,0xaf1,0xa78,0x9fd,0x97f,
+  // 0x900,0x880,0x800,0x77f,0x6ff,0x680,0x602,0x587,
+  // 0x50e,0x498,0x425,0x3b6,0x34c,0x2e6,0x286,0x22b,
+  // 0x1d6,0x187,0x13f,0xfd,0xc3,0x90,0x64,0x40,
+  // 0x24,0x10,0x4,0x0,0x4,0x10,0x24,0x40,
+  // 0x64,0x90,0xc3,0xfd,0x13f,0x187,0x1d6,0x22b,
+  // 0x286,0x2e6,0x34c,0x3b6,0x425,0x498,0x50e,0x587,
+  // 0x602,0x680,0x6ff,0x77f,0x800
+
+  // 256 values, max 4095
+  0x800,0x832,0x864,0x896,0x8c8,0x8fa,0x92c,0x95e,
+  0x98f,0x9c0,0x9f1,0xa22,0xa52,0xa82,0xab1,0xae0,
+  0xb0f,0xb3d,0xb6b,0xb98,0xbc5,0xbf1,0xc1c,0xc47,
+  0xc71,0xc9a,0xcc3,0xceb,0xd12,0xd39,0xd5f,0xd83,
+  0xda7,0xdca,0xded,0xe0e,0xe2e,0xe4e,0xe6c,0xe8a,
+  0xea6,0xec1,0xedc,0xef5,0xf0d,0xf24,0xf3a,0xf4f,
+  0xf63,0xf76,0xf87,0xf98,0xfa7,0xfb5,0xfc2,0xfcd,
+  0xfd8,0xfe1,0xfe9,0xff0,0xff5,0xff9,0xffd,0xffe,
+  0xfff,0xffe,0xffd,0xff9,0xff5,0xff0,0xfe9,0xfe1,
+  0xfd8,0xfcd,0xfc2,0xfb5,0xfa7,0xf98,0xf87,0xf76,
+  0xf63,0xf4f,0xf3a,0xf24,0xf0d,0xef5,0xedc,0xec1,
+  0xea6,0xe8a,0xe6c,0xe4e,0xe2e,0xe0e,0xded,0xdca,
+  0xda7,0xd83,0xd5f,0xd39,0xd12,0xceb,0xcc3,0xc9a,
+  0xc71,0xc47,0xc1c,0xbf1,0xbc5,0xb98,0xb6b,0xb3d,
+  0xb0f,0xae0,0xab1,0xa82,0xa52,0xa22,0x9f1,0x9c0,
+  0x98f,0x95e,0x92c,0x8fa,0x8c8,0x896,0x864,0x832,
+  0x800,0x7cd,0x79b,0x769,0x737,0x705,0x6d3,0x6a1,
+  0x670,0x63f,0x60e,0x5dd,0x5ad,0x57d,0x54e,0x51f,
+  0x4f0,0x4c2,0x494,0x467,0x43a,0x40e,0x3e3,0x3b8,
+  0x38e,0x365,0x33c,0x314,0x2ed,0x2c6,0x2a0,0x27c,
+  0x258,0x235,0x212,0x1f1,0x1d1,0x1b1,0x193,0x175,
+  0x159,0x13e,0x123,0x10a,0xf2,0xdb,0xc5,0xb0,
+  0x9c,0x89,0x78,0x67,0x58,0x4a,0x3d,0x32,
+  0x27,0x1e,0x16,0xf,0xa,0x6,0x2,0x1,
+  0x0,0x1,0x2,0x6,0xa,0xf,0x16,0x1e,
+  0x27,0x32,0x3d,0x4a,0x58,0x67,0x78,0x89,
+  0x9c,0xb0,0xc5,0xdb,0xf2,0x10a,0x123,0x13e,
+  0x159,0x175,0x193,0x1b1,0x1d1,0x1f1,0x212,0x235,
+  0x258,0x27c,0x2a0,0x2c6,0x2ed,0x314,0x33c,0x365,
+  0x38e,0x3b8,0x3e3,0x40e,0x43a,0x467,0x494,0x4c2,
+  0x4f0,0x51f,0x54e,0x57d,0x5ad,0x5dd,0x60e,0x63f,
+  0x670,0x6a1,0x6d3,0x705,0x737,0x769,0x79b,0x7cd
+
 };
 
-dacsample_t dac_buffer_lr[1] = { DAC_SAMPLE_MAX / 2 };
+#define DAC_VOICES_MAX 5
+
+dacsample_t dac_buffer_lr[DAC_BUFFER_SIZE] = { DAC_SAMPLE_MAX / 2 };
 
 float dac_if[8] = {0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0};
 
 /*
  * DAC streaming callback.
  */
-static void end_cb1(DACDriver * dacp, dacsample_t * samples, size_t pos) {
+static void end_cb1(DACDriver * dacp, dacsample_t * samples, size_t rows) {
 
   (void)dacp;
-  (void)pos;
-  //for (uint8_t i = 0; i < DAC_BUFFER_SIZE; i++) {
-  //samples[0] = (dac_buffer[dac_i] + dac_buffer[dac_j]) / 2;
-  //}
+  //(void)dac_buffer;
 
-  uint16_t sample_sum = 0;
   int working_voices = voices;
-  if (working_voices > 3)
-    working_voices = 3;
-  for (int i = 0; i < working_voices; i++) {
-    dac_if[i] = dac_if[i] + ((frequencies[i]*(float)DAC_BUFFER_SIZE)/(float)DAC_SAMPLE_RATE*1.5);
-    while(dac_if[i] >= DAC_BUFFER_SIZE)
-      dac_if[i] = dac_if[i] - DAC_BUFFER_SIZE;
-    sample_sum += dac_buffer[(uint8_t)round(dac_if[i]) % DAC_BUFFER_SIZE] / working_voices;
-  }
+  if (working_voices > DAC_VOICES_MAX)
+    working_voices = DAC_VOICES_MAX;
 
-  if (working_voices > 0) {
-    samples[0] = sample_sum;
-  } else {
-    samples[0] = DAC_SAMPLE_MAX;
+  for (int s = 0; s < rows; s++) {
+    if (working_voices > 0) {
+      uint16_t sample_sum = 0;
+      for (int i = 0; i < working_voices; i++) {
+        dac_if[i] = dac_if[i] + ((frequencies[i]*(float)DAC_BUFFER_SIZE)/(float)DAC_SAMPLE_RATE*1.5);
+        while(dac_if[i] >= DAC_BUFFER_SIZE)
+          dac_if[i] = dac_if[i] - DAC_BUFFER_SIZE;
+        // sine
+        sample_sum += dac_buffer[(uint16_t)round(dac_if[i])] / working_voices;
+        // rising triangle
+        // sample_sum += (uint16_t)round((dac_if[i] * DAC_SAMPLE_MAX) / DAC_BUFFER_SIZE / working_voices );
+        // square (max 5 voices)
+        // sample_sum += ((dac_if[i] > (DAC_BUFFER_SIZE / 2)) ? DAC_SAMPLE_MAX / working_voices: 0);
+      }
+      samples[s] = sample_sum;
+    } else {
+      samples[s] = DAC_SAMPLE_MAX / 2;
+    }
   }
 }
 
@@ -195,7 +236,7 @@ void audio_init() {
   // dacStart(&DACD1, &dac1cfg1);
   // dacStartConversion(&DACD1, &dacgrpcfg1, dac_buffer_lr, 1);
   dacStart(&DACD2, &dac1cfg1);
-  dacStartConversion(&DACD2, &dacgrpcfg1, dac_buffer_lr, 1);
+  dacStartConversion(&DACD2, &dacgrpcfg1, dac_buffer_lr, DAC_BUFFER_SIZE);
 
   gptStart(&GPTD6, &gpt7cfg1);
   gptStartContinuous(&GPTD6, 2U);