I2C communication between a ESP32 and ESP32 Audiokit does not work

[Heute13]

Hello,
I want to send ranom values between 1 and 5 via I2C to my ESP32 Audiokit. Then I want to play a Audiofile, depending on which number arrives. The I2C communication works as long as i only want to print them on the serial monitor. As soon as I want to put in the code for the audio output it doesn't work anymore. The code for the audio output is the example "streams-sdmmc_wav-audiokit" in the arduino-audiotools-library. I think somhow i block the I2C used for the audio processing, when initializing the I2C between the two ESP.

I hope you can help me.
Thank you in advance

Errors that accured where for example:
ES8388 not found on I2C address 10, check wiring,
AudioBoard::driver::begin failed,
setConfig has failed,
AudioDriver init failed

The code for the audiokit I use is:

#include <Wire.h>
#include "FS.h"
#include "SD_MMC.h"
#include "AudioTools.h"
#include "AudioTools/AudioLibs/AudioBoardStream.h"

#define I2C_SLAVE_ADDR 0x08 // I²C-Adresse des Slave

volatile uint8_t sensor = 0; // Zahl von 1 bis 5
volatile uint16_t distance = 0; // Zahl von 0 bis 400

AudioBoardStream i2s(AudioKitEs8388V1);
WAVDecoder wav;
EncodedAudioStream encoded(&i2s, &wav);
File audioFile;
StreamCopy copier(encoded, audioFile);

void setup() {
Serial.begin(115200);
Serial.println("I²C Master bereit");

Wire1.begin(21, 22);

auto config = i2s.defaultConfig(TX_MODE);
config.sd_active = false;
i2s.begin(config);
i2s.setVolume(0.25);

if (!SD_MMC.begin("/sdcard", false)) {
Serial.println("SD_MMC Fehler");
while (true);
}
}

void playAudioFile(uint8_t sensorValue) {
String filename = "/sinus" + String(sensorValue) + ".wav";
Serial.print("Spiele Datei: ");
Serial.println(filename);

if (audioFile) {
audioFile.close();
}

audioFile = SD_MMC.open(filename.c_str());
if (!audioFile) {
Serial.println("Datei nicht gefunden");
return;
}

encoded.begin();
bool bPlaying = true;
while (bPlaying) {
if (copier.copy() != 0) {
bPlaying = false;
}
}
Serial.println("Abspielen beendet");
}

void loop() {
uint8_t bytesReceived = Wire.requestFrom(I2C_SLAVE_ADDR, 3);

if (bytesReceived == 3) {
uint8_t buffer[3];
for (int i = 0; i < bytesReceived; i++) {
buffer[i] = Wire.read();
}

sensor = buffer[0];
distance = buffer[1] | (buffer[2] << 8);


Serial.print("Empfangener Sensorwert: ");
Serial.println(sensor);
Serial.print("Empfangener Distanzwert: ");
Serial.println(distance);


if (sensor >= 1 && sensor <= 5) {
  playAudioFile(sensor);
}

} else {
Serial.println("Fehler beim Empfangen der Daten");
}

delay(1000);
}

This is the o for the ESP32 I use:

#include <Wire.h>

#define I2C_SLAVE_ADDR 0x08

uint8_t sensor = 1;
uint16_t distance = 0;

void setup() {
Wire.begin(I2C_SLAVE_ADDR);
Wire.onRequest(requestEvent);
Serial.begin(115200);
Serial.println("I2C Slave bereit");
}

void loop() {
delay(1000);
}

void requestEvent() {
Serial.println("Master fordert Daten an!");

sensor = (sensor % 5) + 1;
distance = (distance + 20) % 401;

uint8_t data[3];
data[0] = sensor; // Zahl von 1 bis 5
data[1] = distance & 0xFF; // (LSB)
data[2] = (distance >> 8) & 0xFF; // (MSB)

Wire.write(data, 3);
Serial.print("Gesendete Daten: Sensor = ");
Serial.print(sensor);
Serial.print(", Distance = ");
Serial.println(distance);
}

This is the code for the Auiokit whih works but only with serial monitor output of the values

// Master Aktorik
#include <Wire.h>
#include "FS.h"
#include "SD_MMC.h"
#include "AudioTools.h"
#include "AudioTools/AudioLibs/AudioBoardStream.h"

#define I2C_SLAVE_ADDR 0x08

volatile uint8_t sensor = 0;
volatile uint16_t distance = 0;

void setup() {
Wire.begin();
Serial.begin(115200);
Serial.println("I2C Master bereit");
}

void loop() {
uint8_t bytesReceived = Wire.requestFrom(I2C_SLAVE_ADDR, 3);

Serial.print("Bytes empfangen: ");
Serial.println(bytesReceived);

if (bytesReceived == 3) {
uint8_t buffer[3];
for (int i = 0; i < bytesReceived; i++) {
buffer[i] = Wire.read();
}

sensor = buffer[0];

distance = buffer[1] | (buffer[2] << 8);

Serial.print("Empfangener Sensorwert: ");
Serial.println(sensor);
Serial.print("Empfangener Distanzwert: ");
Serial.println(distance);

} else {
Serial.println("Fehler beim Empfangen der Daten");
}

delay(1000);
}

[pschatzmann]

Be careful: for AudioKitEs8388V1 Wire is used with the pins 32 and 33 to communicate with the codec!
And pins 21 and 22 are used by the PA and LED

class PinsAudioKitEs8388v1Class : public DriverPins {
 public:
  PinsAudioKitEs8388v1Class() {
    // sd pins
    addSPI(ESP32PinsSD);
    // add i2c codec pins: scl, sda, port, frequency
    addI2C(PinFunction::CODEC, 32, 33);
    // add i2s pins: mclk, bck, ws,data_out, data_in ,(port)
    addI2S(PinFunction::CODEC, 0, 27, 25, 26, 35);

    // add other pins
    addPin(PinFunction::KEY, 36, PinLogic::InputActiveLow, 1);
    addPin(PinFunction::KEY, 13, PinLogic::InputActiveLow, 2);
    addPin(PinFunction::KEY, 19, PinLogic::InputActiveLow, 3);
    addPin(PinFunction::KEY, 23, PinLogic::InputActiveLow, 4);
    addPin(PinFunction::KEY, 18, PinLogic::InputActiveLow, 5);
    addPin(PinFunction::KEY, 5, PinLogic::InputActiveLow, 6);
    addPin(PinFunction::AUXIN_DETECT, 12, PinLogic::InputActiveLow);
    addPin(PinFunction::HEADPHONE_DETECT, 39, PinLogic::InputActiveLow);
    addPin(PinFunction::PA, 21, PinLogic::Output);
    addPin(PinFunction::LED, 22, PinLogic::Output);
  }
};

[Heute13]

Thank you for the hint. So where do I find two pins on the Audiokit I can use for I2C communication? And is it possible to use Wire1?

[Heute13]

I know thought of using Wire1.begin(5, 22);
because
I do not need the key 8 and the LED. But I still get no connection. The Master sends no request to the slave and the slave no answer back.

[Heute13]

As soon as I remove i2s.begin(config); the I2C ommunication works. Could it be that I2S and I2C interfere with each other?

[Heute13]

I have found a solution to my Problem. I initialize I2C, send the data, then I deinitialize I2C and initialize I2S. Then I want to open the audiofile on the sd card and play it, but the File can not be found. I double checked if the file name is right.

Code:
#include <Wire.h>
#include "FS.h"
#include "SD_MMC.h"
#include "AudioTools.h"
#include "AudioTools/AudioLibs/AudioBoardStream.h"

// I²C-Konstanten
#define I2C_SLAVE_ADDR 0x55 // I²C-Adresse des Slave
#define sda 5
#define scl 18

// Array mit festen Dateinamen
const char *audioFiles[] = {
"/sinus1.wav", // Index 0 -> Sensor 1
"/sinus2.wav", // Index 1 -> Sensor 2
"/sinus3.wav", // Index 2 -> Sensor 3
"/sinus4.wav", // Index 3 -> Sensor 4
"/sinus5.wav" // Index 4 -> Sensor 5
};

// Variablen für empfangene Werte
volatile uint8_t sensor = 0; // Zahl von 1 bis 5
volatile uint16_t distance = 0; // Zahl von 0 bis 400

// Audio-Objekte
AudioBoardStream i2s(AudioKitEs8388V1);
WAVDecoder wav;
EncodedAudioStream encoded(&i2s, &wav);
File audioFile;
StreamCopy copier(encoded, audioFile);

bool isI2SInitialized = false; // Zustand von I²S

// Funktion zum Initialisieren von I²C
void initI2C() {
Wire1.begin(sda, scl); // I²C starten
Serial.println("I²C initialisiert");
}

// Funktion zum Beenden von I²C
void deinitI2C() {
Wire1.end(); // I²C stoppen
Serial.println("I²C deaktiviert");
}

// Funktion zum Initialisieren von I²S
void initI2S() {
if (!isI2SInitialized) {
auto config = i2s.defaultConfig(TX_MODE);
config.sd_active = false;
i2s.begin(config);
isI2SInitialized = true;
Serial.println("I²S initialisiert");
}
}

// Funktion zum Beenden von I²S
void deinitI2S() {
if (isI2SInitialized) {
i2s.end(); // I²S stoppen
isI2SInitialized = false;
Serial.println("I²S deaktiviert");
}
}

// Funktion zum Abspielen einer Audiodatei basierend auf dem Sensorwert
void playAudioFile(uint8_t sensorValue) {
if (sensorValue < 1 || sensorValue > 5) {
Serial.println("Ungültiger Sensorwert für Audioauswahl");
return;
}

// Wähle die Datei basierend auf dem Sensorwert
const char *filename = audioFiles[sensorValue - 1]; // -1, da Array bei 0 beginnt
Serial.print("Spiele Datei: ");
Serial.println(filename);

// Alte Datei schließen
if (audioFile) {
audioFile.close();
}

// Neue Datei öffnen
audioFile = SD_MMC.open(filename);
if (!audioFile) {
Serial.println("Datei nicht gefunden");
return;
}

// Dekoder-Stream starten
encoded.begin();
bool bPlaying = true;
while (bPlaying) {
if (copier.copy() != 0) {
bPlaying = false;
}
}
Serial.println("Abspielen beendet");
}

void setup() {
// Serieller Monitor
Serial.begin(115200);
Serial.println("Systemstart");

// SD-Karte einbinden
if (!SD_MMC.begin("/sdcard", false)) {
Serial.println("SD_MMC Fehler");
while (true);
}
}

void loop() {
// Phase 1: I²C aktivieren und Daten lesen
initI2C(); // I²C initialisieren
delay(10); // Kurze Verzögerung zur Stabilisierung

// Daten vom Slave abrufen
uint8_t bytesReceived = Wire1.requestFrom(I2C_SLAVE_ADDR, 3);
Serial.print("Bytes empfangen: ");
Serial.println(bytesReceived);

if (bytesReceived == 3) {
uint8_t buffer[3];
for (int i = 0; i < bytesReceived; i++) {
buffer[i] = Wire1.read(); // Lese die empfangenen Bytes in das Array
}

// Sensor- und Distanzwerte aktualisieren
sensor = buffer[0];
distance = buffer[1] | (buffer[2] << 8);

// Ausgabe der empfangenen Werte
Serial.print("Empfangener Sensorwert: ");
Serial.println(sensor);
Serial.print("Empfangener Distanzwert: ");
Serial.println(distance);

} else {
Serial.println("Fehler beim Empfangen der Daten");
}

deinitI2C(); // I²C deaktivieren

// Phase 2: I²S aktivieren und Audio abspielen
initI2S(); // I²S initialisieren
delay(10); // Kurze Verzögerung zur Stabilisierung

// Audio abspielen basierend auf Sensorwert
playAudioFile(sensor);

deinitI2S(); // I²S deaktivieren
delay(1000); // Wartezeit zwischen den Durchläufen
}

[pschatzmann]

Did you try to separate the I2S from the I2C processing in separate tasks ?

[Heute13]

What do you mean? Why do I use SDMMC and SD? I am sorry if this is a dumb question, but I am new at this.

[Heute13]

I2S works always. I2C only when I2S is not initialzed.

[pschatzmann]

There are different SD APIs: the Arduino SD library uses SPI, SDMMC uses the ESP32 specific API

[Heute13]

Do I understand it right that I have to use sdmmc with the esp32 audiokit because it is everything permanently connected? WIth SD i would need the CS pin 5 which is not connected , am I right?

[pschatzmann]

No, you can also use the SD library which is included or the SDFAT library: You just need to set up the SPI with the correct pins.

This is something that this library does automatically like in this example.