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// Set up I2S Processor configuration
void i2s_install() {
  // Set up I2S Processor configuration
  i2s_config_t i2s_config = {
    .mode = (i2s_mode_t)(I2S_MODE_MASTER | I2S_MODE_RX),
    .sample_rate = 4000, // or 44100 if you like
    .bits_per_sample = I2S_BITS_PER_SAMPLE_32BIT,
    .channel_format = I2S_CHANNEL_FMT_ONLY_LEFT, // Ground the L/R pin on the INMP441.
    .communication_format = (i2s_comm_format_t)(I2S_COMM_FORMAT_STAND_I2S),
    .intr_alloc_flags = ESP_INTR_FLAG_LEVEL1,
    .dma_buf_count = bufferCount,
    .dma_buf_len = bufferLen,
    .use_apll = false,
    .tx_desc_auto_clear = false,
    .fixed_mclk = 0,
  };

  i2s_driver_install(I2S_PORT, &i2s_config, 0, NULL);
}

Code: Select all

while (1)
    {
        vTaskDelay(1); // Feed for watchdog, if not watchdog timer will be triggered!

        i2s_read(I2S_PORT, &buffer32, sizeof(buffer32), &bytesRead, 100);
        int samplesRead = bytesRead / 4;

        for (uint8_t i = 0; i < samplesRead; i++) {
            uint8_t mid = buffer32[i * 4 + 2];
            uint8_t msb = buffer32[i * 4 + 3];
            uint16_t raw = (((uint32_t)msb) << 8) + ((uint32_t)mid);
            memcpy(&buffer16[i], &raw, sizeof(raw)); // Copy so sign bits aren't interfered with somehow.
            printf("%d %d %d\n", 3000, -3000, buffer16[i]);
        }
    }