Add embedded MP3 playback test sketch

Software/UPSoftware/UPSoftware.ino

@@ -1,82 +1,79 @@
-#include <Arduino.h>
-#include "driver/twai.h"
-#include "MeyCan.h"
-
-// https://github.com/espressif/arduino-esp32/blob/master/libraries/ESP32/examples/TWAI/TWAIreceive/TWAIreceive.ino
-
-#define RX_PIN 2
-#define TX_PIN 3
-
-void DebugBlink(int d) {
-  pinMode(20, OUTPUT);
-  while (true) {
-
-    digitalWrite(20, HIGH);
-    delay(d);
-    digitalWrite(20, LOW);
-    delay(d);
-  }
-}
-
-bool driver_installed = false;
-void setup() {
-  Serial.begin(9600);
-  SPI.begin();
-
-  // Explicit GND for LED and Input
-  pinMode(21, OUTPUT);
-  digitalWrite(21, LOW);
-
-  // Initialize configuration structures using macro initializers
-  twai_general_config_t g_config = TWAI_GENERAL_CONFIG_DEFAULT((gpio_num_t)TX_PIN, (gpio_num_t)RX_PIN, TWAI_MODE_NORMAL);
-  twai_timing_config_t t_config = TWAI_TIMING_CONFIG_1MBITS();  //Look in the api-reference for other speed sets.
-  twai_filter_config_t f_config = TWAI_FILTER_CONFIG_ACCEPT_ALL();
-
-
-  if (twai_driver_install(&g_config, &t_config, &f_config) == ESP_OK) {
-    Serial.println("Driver installed");
-  } else {
-    DebugBlink(100);
-    return;
-  }
-
-
-
-  esp_err_t e = twai_start();
-  // Start TWAI driver
-  if (e == ESP_OK) {
-    driver_installed = true;
-  } else {
-    DebugBlink(500);
-    return;
-  }
-
-
-  SetDevicedId(0x05, 0x1F);
-
-  SetMeyPin(1, 5);
-  SetMeyPin(2, 6);
-  SetMeyPin(3, 7);
-  SetMeyPin(4, 8);
-  SetMeyPin(5, 9);
-  SetMeyPin(6, 10);
-  SetMeyPin(7, 20);
-
-  SetupMeyCan(8, 1, 3);
-}
-
-twai_message_t frame;
-void loop() {
-
-  if (!driver_installed) {
-    // Driver not installed
-    DebugBlink(2000);
-    return;
-  }
-
-  CheckMeyPinsTriggered();
-  if (twai_receive(&frame, 0) == ESP_OK) {
-
-    HandleFrame(&frame);
-  }
-}
+#include <Arduino.h>
+#include <driver/i2s.h>
+#include <MP3DecoderHelix.h>
+#include "positive_sound_mp3.h"
+
+using namespace libhelix;
+
+constexpr i2s_port_t I2S_PORT = I2S_NUM_0;
+constexpr int I2S_BCLK = 6;
+constexpr int I2S_LRC = 7;
+constexpr int I2S_DIN = 5;
+constexpr float OUTPUT_GAIN = 0.35f;
+
+MP3DecoderHelix mp3;
+
+bool i2s_initialized = false;
+int current_sample_rate = 0;
+int current_channels = 0;
+
+void configureI2s(int sample_rate, int channels) {
+  if (!i2s_initialized) {
+    i2s_config_t i2s_config = {};
+    i2s_config.mode = static_cast<i2s_mode_t>(I2S_MODE_MASTER | I2S_MODE_TX);
+    i2s_config.sample_rate = sample_rate;
+    i2s_config.bits_per_sample = I2S_BITS_PER_SAMPLE_16BIT;
+    i2s_config.channel_format = I2S_CHANNEL_FMT_RIGHT_LEFT;
+    i2s_config.communication_format = I2S_COMM_FORMAT_STAND_I2S;
+    i2s_config.intr_alloc_flags = ESP_INTR_FLAG_LEVEL1;
+    i2s_config.dma_buf_count = 8;
+    i2s_config.dma_buf_len = 256;
+    i2s_config.use_apll = false;
+    i2s_config.tx_desc_auto_clear = true;
+    i2s_config.fixed_mclk = 0;
+
+    i2s_pin_config_t pin_config = {};
+    pin_config.bck_io_num = I2S_BCLK;
+    pin_config.ws_io_num = I2S_LRC;
+    pin_config.data_out_num = I2S_DIN;
+    pin_config.data_in_num = I2S_PIN_NO_CHANGE;
+
+    i2s_driver_install(I2S_PORT, &i2s_config, 0, nullptr);
+    i2s_set_pin(I2S_PORT, &pin_config);
+    i2s_zero_dma_buffer(I2S_PORT);
+    i2s_initialized = true;
+  }
+
+  if (sample_rate != current_sample_rate || channels != current_channels) {
+    i2s_channel_t channel_mode =
+        channels == 1 ? I2S_CHANNEL_MONO : I2S_CHANNEL_STEREO;
+    i2s_set_clk(I2S_PORT, sample_rate, I2S_BITS_PER_SAMPLE_16BIT, channel_mode);
+    current_sample_rate = sample_rate;
+    current_channels = channels;
+  }
+}
+
+void audioDataCallback(MP3FrameInfo &info, int16_t *pcm_buffer, size_t len, void *) {
+  configureI2s(info.samprate, info.nChans);
+
+  for (size_t i = 0; i < len; ++i) {
+    pcm_buffer[i] = static_cast<int16_t>(pcm_buffer[i] * OUTPUT_GAIN);
+  }
+
+  size_t bytes_written = 0;
+  i2s_write(I2S_PORT, pcm_buffer, len * sizeof(int16_t), &bytes_written,
+            portMAX_DELAY);
+}
+
+void setup() {
+  Serial.begin(115200);
+  mp3.setDataCallback(audioDataCallback);
+  mp3.begin();
+  Serial.println("MP3 playback started");
+}
+
+void loop() {
+  mp3.write(positive_sound_short_mp3, positive_sound_short_mp3_len);
+  mp3.begin();
+  delay(20);
+}