simple_dac.cpp

#include "simple_dac.h"


Audio::Audio(const uint8_t BCLK, const uint8_t LRC, const uint8_t DOUT) {
    //i2s configuration
    m_i2s_num = I2S_NUM_0; // i2s port number
    m_i2s_config.mode                 = (i2s_mode_t)(I2S_MODE_MASTER | I2S_MODE_TX);
    m_i2s_config.sample_rate          = 44100;
    m_i2s_config.bits_per_sample      = I2S_BITS_PER_SAMPLE_32BIT;
    m_i2s_config.channel_format       = I2S_CHANNEL_FMT_RIGHT_LEFT;
    m_i2s_config.communication_format = (i2s_comm_format_t)(I2S_COMM_FORMAT_I2S | I2S_COMM_FORMAT_I2S_MSB);
    m_i2s_config.intr_alloc_flags     = ESP_INTR_FLAG_LEVEL1; // high interrupt priority
    m_i2s_config.dma_buf_count        = 8;      // max buffers
    m_i2s_config.dma_buf_len          = 1024;   // max value
    m_i2s_config.use_apll             = APLL_ENABLE;
    m_i2s_config.tx_desc_auto_clear   = true;   // new in V1.0.1
    m_i2s_config.fixed_mclk           = I2S_PIN_NO_CHANGE;

    i2s_driver_install((i2s_port_t)m_i2s_num, &m_i2s_config, 0, NULL);

    m_BCLK=BCLK;                       // Bit Clock
    m_LRC=LRC;                         // Left/Right Clock
    m_DOUT=DOUT;                       // Data Out
    setPinout(m_BCLK, m_LRC, m_DOUT, m_DIN);
}

Audio::~Audio() {
    I2Sstop(m_i2s_num);
}

esp_err_t Audio::I2Sstart(uint8_t i2s_num) {
    return i2s_start((i2s_port_t) i2s_num);
}

esp_err_t Audio::I2Sstop(uint8_t i2s_num) {
    return i2s_stop((i2s_port_t) i2s_num);
}

bool Audio::setPinout(uint8_t BCLK, uint8_t LRC, uint8_t DOUT, int8_t DIN) {
    m_BCLK = BCLK;            // Bit Clock
    m_LRC = LRC;              // Left/Right Clock
    m_DOUT = DOUT;            // Data Out
    m_DIN = DIN;              // Data In

    i2s_pin_config_t pins = {
            .bck_io_num   = m_BCLK,
            .ws_io_num    = m_LRC,     //  wclk,
            .data_out_num = m_DOUT,
            .data_in_num  = m_DIN
    };
    const esp_err_t result = i2s_set_pin((i2s_port_t) m_i2s_num, &pins);
    return (result == ESP_OK);
}

int Audio::play32BitSample(int32_t sample[2]) {
    esp_err_t err = i2s_write((i2s_port_t) m_i2s_num, (const char*) sample, sizeof(int32_t) * 2, &m_i2s_bytesWritten, 1000);
    if(err != ESP_OK) {
        log_e("ESP32 Errorcode %i", err);
        return 0;
    }
    if(m_i2s_bytesWritten < sizeof(int32_t) * 2) {
        log_e("Can't stuff any more in I2S..."); // increase waitingtime or outputbuffer
        return 0;
    }
    return m_i2s_bytesWritten;
}

int Audio::play16BitSample(int16_t sample[2]) {
    esp_err_t err = i2s_write((i2s_port_t) m_i2s_num, (const char*) sample, sizeof(int16_t) * 2, &m_i2s_bytesWritten, 1000);
    if(err != ESP_OK) {
        log_e("ESP32 Errorcode %i", err);
        return 0;
    }
    if(m_i2s_bytesWritten < sizeof(int16_t) * 2) {
        log_e("Can't stuff any more in I2S..."); // increase waitingtime or outputbuffer
        return 0;
    }
    return m_i2s_bytesWritten;
}