Fixed summing of signals as integers.

Added midinotes.h.
Added overload detection.
Small fixes.

MicroDexed.ino

@@ -46,6 +46,8 @@ MIDI_CREATE_INSTANCE(HardwareSerial, Serial1, MIDI);
 Dexed* dexed = new Dexed(SAMPLE_RATE);
 bool sd_card_available = false;
 uint8_t bank = DEFAULT_SYSEXBANK;
+uint32_t xrun = 0;
+uint32_t overload = 0;
 
 #ifdef MASTER_KEY_MIDI
 bool master_key_enabled = false;
@@ -159,16 +161,11 @@ void loop()
     if (!queue1.available())
       continue;
 
-#if defined(SHOW_DEXED_TIMING) || defined(SHOW_XRUN)
     elapsedMicros t1;
-#endif
     dexed->getSamples(AUDIO_BLOCK_SAMPLES, audio_buffer);
-
-#ifdef SHOW_XRUN
     uint32_t t2 = t1;
     if (t2 > 2900) // everything greater 2.9ms is a buffer underrun!
-      Serial.println(F("XRUN"));
+      xrun++;
-#endif
 #ifdef SHOW_DEXED_TIMING
     Serial.println(t1, DEC);
 #endif
@@ -209,8 +206,7 @@ void handle_midi_input(void)
 void note_on(void)
 {
   randomSeed(analogRead(A0));
-  queue_midi_event(0x90, TEST_NOTE, random(TEST_VEL_MIN, TEST_VEL_MAX));
+  queue_midi_event(0x90, TEST_NOTE, random(TEST_VEL_MIN, TEST_VEL_MAX));           // 1
-  // 1
   queue_midi_event(0x90, TEST_NOTE + 5, random(TEST_VEL_MIN, TEST_VEL_MAX));       // 2
   queue_midi_event(0x90, TEST_NOTE + 8, random(TEST_VEL_MIN, TEST_VEL_MAX));       // 3
   queue_midi_event(0x90, TEST_NOTE + 12, random(TEST_VEL_MIN, TEST_VEL_MAX));      // 4
@@ -328,12 +324,12 @@ bool queue_midi_event(uint8_t type, uint8_t data1, uint8_t data2)
   if (type == 0x80 && data1 == MASTER_KEY_MIDI) // Master key released
   {
     master_key_enabled = false;
-    Serial.println("Master key disabled");
+    Serial.println(F("Master key disabled"));
   }
   else if (type == 0x90 && data1 == MASTER_KEY_MIDI) // Master key pressed
   {
     master_key_enabled = true;
-    Serial.println("Master key enabled");
+    Serial.println(F("Master key enabled"));
   }
   else
   {
@@ -469,6 +465,10 @@ void show_cpu_and_mem_usage(void)
   Serial.print(AudioMemoryUsage(), DEC);
   Serial.print(F("   MEM MAX:"));
   Serial.print(AudioMemoryUsageMax(), DEC);
+  Serial.print(F("   XRUN:"));
+  Serial.print(xrun, DEC);
+  Serial.print(F("   OVERLOAD:"));
+  Serial.print(overload, DEC);
   Serial.println();
   AudioProcessorUsageMaxReset();
   AudioMemoryUsageMaxReset();

config.h

@@ -21,9 +21,10 @@
    Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
 
 */
+#include "midinotes.h"
 
 //#define TEST_MIDI 1
-#define TEST_NOTE 40
+#define TEST_NOTE MIDI_E2
 #define TEST_VEL_MIN 60
 #define TEST_VEL_MAX 110
 
@@ -43,12 +44,12 @@
 #define DEFAULT_SYSEXBANK 0
 #define DEFAULT_SYSEXSOUND 0
 
-#define MASTER_KEY_MIDI 84      // C6
+#define MASTER_KEY_MIDI MIDI_C6
-#define MASTER_NUM1 24          // C1
+#define MASTER_NUM1 MIDI_C1
-#define MASTER_BANK_SELECT 83   // B5
 
 #define USE_TEENSY_DSP 1
 #define SUM_UP_AS_INT 1
+#define REDUCE_LOUDNESS 2
 
 // Use these with the Teensy Audio Shield
 #define SDCARD_CS_PIN    10

dexed.cpp

@@ -39,6 +39,7 @@
 #endif
 
 extern uint8_t bank;
+extern uint32_t overload;
 extern bool load_sysex(uint8_t bank, uint8_t voice_number);
 
 Dexed::Dexed(int rate)
@@ -142,6 +143,9 @@ void Dexed::getSamples(uint16_t n_samples, int16_t* buffer)
 
     int32_t lfovalue = lfo.getsample();
     int32_t lfodelay = lfo.getdelay();
+#ifdef SUM_UP_AS_INT
+    int32_t sum;
+#endif
 
     for (uint8_t note = 0; note < max_notes; ++note) {
       if (voices[note].live) {
@@ -154,24 +158,34 @@ void Dexed::getSamples(uint16_t n_samples, int16_t* buffer)
 #else
           int32_t clip_val = val < -(1 << 24) ? 0x8000 : val >= (1 << 24) ? 0x7fff : val >> 9;
 #endif
+          if (clip_val != (val>>9))
+            overload++;
 #ifdef SUM_UP_AS_INT
-          int32_t tmp = buffer[i + j] + (clip_val >> 1);
+          sum = buffer[i + j] + (clip_val >> REDUCE_LOUDNESS);
-          if (buffer[i + j] > 0 && clip_val > 0)
+/*
+          if (buffer[i + j] > 0 && clip_val > 0 && sum < 0)
           {
-            if ((tmp < buffer[i + j]) && (tmp < clip_val))
+            sum = 0x8000;
-              tmp = 0x8000;
           }
-          else if (buffer[i + j] < 0 && clip_val < 0)
+          else if (buffer[i + j] < 0 && clip_val < 0 && sum > 0)
           {
-            if ((tmp > buffer[i + j]) && (tmp > clip_val))
+            sum = 0x7FFF;
-              tmp = 0x7FFF;
           }
-          buffer[i + j] = tmp;
+          */
+          buffer[i + j] = sum;
           audiobuf.get()[j] = 0;
 #else
-          float f = static_cast<float>(clip_val >> 1) / 0x8000;
+          float f = static_cast<float>(clip_val >> REDUCE_LOUDNESS) / 0x8000;
-          if (f > 1) f = 1;
+          if (f > 1)
-          if (f < -1) f = -1;
+          {
+            f = 1;
+            overload++;
+          }
+          else if (f < -1)
+          {
+            f = -1;
+            overload++;
+          }
           sumbuf[j] += f;
           audiobuf.get()[j] = 0;
 #endif

midinotes.h

@@ -0,0 +1,97 @@
+/*************************************************
+ * MIDI note values
+ *************************************************/
+
+#ifndef _MIDINOTES_H
+#define _MIDINOTES_H
+
+#define MIDI_A0   21
+#define MIDI_AIS0 22
+#define MIDI_B0   23
+#define MIDI_C1   24
+#define MIDI_CIS1 25
+#define MIDI_D1   26
+#define MIDI_DIS1 27
+#define MIDI_E1   28
+#define MIDI_F1   29
+#define MIDI_FIS1 30 
+#define MIDI_G1   31
+#define MIDI_GIS1 32
+#define MIDI_A1   33
+#define MIDI_AIS1 34
+#define MIDI_B1   35
+#define MIDI_C2   36
+#define MIDI_CIS2 37
+#define MIDI_D2   38
+#define MIDI_DIS2 39
+#define MIDI_E2   40
+#define MIDI_F2   41
+#define MIDI_FIS2 42
+#define MIDI_G2   43
+#define MIDI_GIS2 44
+#define MIDI_A2   45
+#define MIDI_AIS2 46
+#define MIDI_B2   47 
+#define MIDI_C3   48
+#define MIDI_CIS3 49
+#define MIDI_D3   50
+#define MIDI_DIS3 51
+#define MIDI_E3   52
+#define MIDI_F3   53
+#define MIDI_FIS3 54
+#define MIDI_G3   55
+#define MIDI_GIS3 56
+#define MIDI_A3   57
+#define MIDI_AIS3 58
+#define MIDI_B3   59
+#define MIDI_C4   60
+#define MIDI_CIS4 61
+#define MIDI_D4   62
+#define MIDI_DIS4 63
+#define MIDI_E4   64
+#define MIDI_F4   65
+#define MIDI_FIS4 66
+#define MIDI_G4   67
+#define MIDI_GIS4 68
+#define MIDI_A4   69
+#define MIDI_AIS4 70
+#define MIDI_B4   71
+#define MIDI_C5   72
+#define MIDI_CIS5 73
+#define MIDI_D5   74
+#define MIDI_DIS5 75
+#define MIDI_E5   76
+#define MIDI_F5   77
+#define MIDI_FIS5 78
+#define MIDI_G5   79
+#define MIDI_GIS5 80
+#define MIDI_A5   81
+#define MIDI_AIS5 82
+#define MIDI_B5   83
+#define MIDI_C6   84
+#define MIDI_CIS6 85
+#define MIDI_D6   86
+#define MIDI_DIS6 87
+#define MIDI_E6   88
+#define MIDI_F6   89
+#define MIDI_FIS6 90
+#define MIDI_G6   91
+#define MIDI_GIS6 92
+#define MIDI_A6   93
+#define MIDI_AIS6 94
+#define MIDI_B6   95
+#define MIDI_C7   96
+#define MIDI_CIS7 97
+#define MIDI_D7   98
+#define MIDI_DIS7 99
+#define MIDI_E7   100
+#define MIDI_F7   101
+#define MIDI_FIS7 102
+#define MIDI_G7   103
+#define MIDI_GIS7 104
+#define MIDI_A7   105
+#define MIDI_AIS7 106
+#define MIDI_B7   107
+#define MIDI_C8   108
+
+#endif