Yet another PCM1808 ADC + PCM5102 DAC project

[alw1746]

There are similar projects where a PCM1808 ADC is used to connect an analog audio source, run through an ESP32 with Audio Tools and output to a PCM5102 DAC and stereo amp. But the information is a bit scattered and lacking in detail so I created this little setup complete with image, code and schematic. If you follow this exactly, music will flow and all is golden.

Sketch

 /**
 * @file streams-i2s-i2s-2.ino
 * @brief Copy audio from I2S to I2S: We use 2 different i2s ports!
 * @author Phil Schatzmann
 * @copyright GPLv3
 */

#include "AudioTools.h"
 
AudioInfo info_in(44100, 2, 32);
AudioInfo info_out(44100, 2, 32);
I2SStream in;
I2SStream out;
//NumberFormatConverterStream nfc(out);    //**did not work**
//StreamCopy copier(nfc, in);              //**did not work**
StreamCopy copier(out, in); // copies sound into i2s

// Arduino Setup
void setup(void) {  
  // Open Serial 
  Serial.begin(115200);
  // change to Warning to improve the quality
  AudioToolsLogger.begin(Serial, AudioToolsLogLevel::Warning); 

  //nfc.begin(32,16);    //**did not work**

  // start I2S in - (PC soundcard  -> PCM1808)
  Serial.println("starting I2S...");
  auto config_in = in.defaultConfig(RX_MODE);
  config_in.copyFrom(info_in); 
  config_in.i2s_format = I2S_STD_FORMAT;
  config_in.is_master = true;
  config_in.port_no = 0;
  config_in.pin_bck = 18;
  config_in.pin_ws = 21;
  config_in.pin_data = 19;
  config_in.pin_mck = 3;
  in.begin(config_in);

  // start I2S out - (PCM5102 -> stereo amp)
  auto config_out = out.defaultConfig(TX_MODE);
  config_out.copyFrom(info_out); 
  config_out.i2s_format = I2S_STD_FORMAT;
  config_out.is_master = true;
  config_out.port_no = 1;
  //config_out.bits_per_sample = 16;    //**did not work**
  config_out.bits_per_sample = 32;
  config_out.pin_bck = 25;
  config_out.pin_ws = 13;
  config_out.pin_data = 26;
  out.begin(config_out);

  Serial.println("I2S started...");
}

// Arduino loop - copy sound to out 
void loop() {
  copier.copy();
}

The PCM1808 board is a generic ebay item while the PCM5102 is from Adafruit. Note, I tried to convert the 32-bit input from PCM1808 to a 16-bit depth for the PCM5102 but all I got was silence so not sure why it did not work. See the commented lines in sketch. Ignore the potentiometer connections, they are leftover from a previous project.