keira: liltracker: fix sine waveform phase shift, increase sample rat…

…e to 44100, increase mixer buf size to 512, increase DMA buf count to 4
and3rson · Apr 15, 2024 · aff663f · aff663f
1 parent ff664c3
commit aff663f
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Showing 4 changed files with 6 additions and 4 deletions.
diff --git a/firmware/keira/src/apps/liltracker/effects.cpp b/firmware/keira/src/apps/liltracker/effects.cpp
@@ -56,6 +56,8 @@ void effect_vibrato(float time, float relTime, float* frequency, float* amplitud
     uint8_t vibratoDepth = param & 0x0F;
 
     // Calculate the depth of vibrato in terms of radians
+    // TODO: This is not really correct: 1 unit of phase is not 1 semitone, but 1 Hz.
+    // So we should convert below value to Hz based on the current frequency of the note.
     float phaseModulation = vibratoDepth / 15.0f * lilka::fSin360(time * vibratoFrequency * 360);
 
     // Apply the vibrato phase modulation

diff --git a/firmware/keira/src/apps/liltracker/mixer.cpp b/firmware/keira/src/apps/liltracker/mixer.cpp
@@ -37,7 +37,7 @@ Mixer::Mixer() :
         .communication_format =
             (esp_i2s::i2s_comm_format_t)(esp_i2s::I2S_COMM_FORMAT_STAND_I2S | esp_i2s::I2S_COMM_FORMAT_STAND_MSB),
         .intr_alloc_flags = ESP_INTR_FLAG_LEVEL1,
-        .dma_buf_count = 3,
+        .dma_buf_count = 4,
         .dma_buf_len = MIXER_BUFFER_SIZE,
         .use_apll = false,
         .tx_desc_auto_clear = true,

diff --git a/firmware/keira/src/apps/liltracker/mixer.h b/firmware/keira/src/apps/liltracker/mixer.h
@@ -7,8 +7,8 @@
 #include "waveforms.h"
 #include "effects.h"
 
-#define MIXER_BUFFER_SIZE        256
-#define SAMPLE_RATE              16000
+#define MIXER_BUFFER_SIZE        512
+#define SAMPLE_RATE              44100
 #define MIXER_BUFFER_DURATION_MS (MIXER_BUFFER_SIZE * 1000 / SAMPLE_RATE)
 #define SECONDS_PER_SAMPLE       (1.0f / SAMPLE_RATE)
 

diff --git a/firmware/keira/src/apps/liltracker/waveforms.cpp b/firmware/keira/src/apps/liltracker/waveforms.cpp
@@ -21,7 +21,7 @@ float triangle(float time, float frequency, float amplitude, float phase) {
 // }
 
 float fast_sine(float time, float frequency, float amplitude, float phase) {
-    return amplitude * lilka::fSin360(frequency * 360 * time + phase);
+    return amplitude * lilka::fSin360(frequency * 360 * time + phase * 360);
 }
 
 // Square wave function