Multi DAC (PCM5102A)

[Nagathryn]

Hi
Is it possible on an ESP32 to have two DACs sharing the same clocks (BCK/LCK) but with different data lines and use the I2S_CHANNEL_FMT_ONLY_RIGHT and LEFT formats? Is this the right approach? And if so, how can I assign two I2S configurations to the same BluetoothA2DPSink object?

Example code without bt sink

#include <driver/i2s.h>

#define I2S_BCK   26  // BCLK
#define I2S_LRCK  25  // LRCK
#define I2S_DATA1 22  // Data PCM5102 #1 (Gauche)
#define I2S_DATA2 23  // Data PCM5102 #2 (Droite)

void setup() {
    Serial.begin(115200);

    // Configuration I2S pour la voie gauche
    i2s_config_t i2s_config1 = {
        .mode = (i2s_mode_t)(I2S_MODE_MASTER | I2S_MODE_TX),  
        .sample_rate = 44100,   
        .bits_per_sample = I2S_BITS_PER_SAMPLE_16BIT,  
        .channel_format = I2S_CHANNEL_FMT_ONLY_LEFT,  // **Uniquement la voie gauche**
        .communication_format = I2S_COMM_FORMAT_I2S,   
        .intr_alloc_flags = 0,  
        .dma_buf_count = 8,    
        .dma_buf_len = 64      
    };

    // Configuration I2S pour la voie droite
    i2s_config_t i2s_config2 = {
        .mode = (i2s_mode_t)(I2S_MODE_MASTER | I2S_MODE_TX),  
        .sample_rate = 44100,   
        .bits_per_sample = I2S_BITS_PER_SAMPLE_16BIT,  
        .channel_format = I2S_CHANNEL_FMT_ONLY_RIGHT,  // **Uniquement la voie droite**
        .communication_format = I2S_COMM_FORMAT_I2S,   
        .intr_alloc_flags = 0,  
        .dma_buf_count = 8,    
        .dma_buf_len = 64      
    };

    i2s_pin_config_t pin_config1 = {
        .bck_io_num = I2S_BCK,
        .ws_io_num = I2S_LRCK,
        .data_out_num = I2S_DATA1,
        .data_in_num = I2S_PIN_NO_CHANGE 
    };

    i2s_pin_config_t pin_config2 = {
        .bck_io_num = I2S_BCK,
        .ws_io_num = I2S_LRCK,
        .data_out_num = I2S_DATA2,
        .data_in_num = I2S_PIN_NO_CHANGE 
    };

    i2s_driver_install(I2S_NUM_0, &i2s_config1, 0, NULL);
    i2s_set_pin(I2S_NUM_0, &pin_config1);

    i2s_driver_install(I2S_NUM_1, &i2s_config2, 0, NULL);
    i2s_set_pin(I2S_NUM_1, &pin_config2);

    // Add bt sink start 
}

void loop() {
    // Envoyer les données audio séparées à chaque DAC
}

Thank you for your feedback!

[pschatzmann]

I don't think so and not via the standard API, but you would need to study the Technical Sheet to figure out if there is some way around this.
Using the AudioTools it would be pretty easy to split up and send the output to multiple I2S ports using separate pins.

You can try to define one port as master and the other as slave.
But in any case you need to make sure that you write to both ports!