Update README.md

README.md

 # ESP32-audioI2S
+Play mp3 files via I2S with external hardware.
+HELIX-mp3 decoder is included.
+Works with MAX98357A (3 Watt amplifier with DAC), connected three lines (DOUT, BLCK, LRC) to I2S.
+Other HW (UDA1334A ...) may work but not tested.
+
+```` c++
+#include "Arduino.h"
+#include "audioI2S/Audio.h"
+#include "SD.h"
+#include "FS.h"
+
+// Digital I/O used
+#define SD_CS          5
+#define SPI_MOSI      23
+#define SPI_MISO      19
+#define SPI_SCK       18
+#define I2S_DOUT      25
+#define I2S_BCLK      27
+#define I2S_LRC       26
+
+Audio audio;
+
+void setup() {
+    SPI.begin(SPI_SCK, SPI_MISO, SPI_MOSI);
+    Serial.begin(115200);
+    SD.begin(SD_CS);
+    audio.connecttoSD("320k_test.mp3");
+    audio.setPinout(I2S_BCLK, I2S_LRC, I2S_DOUT);
+    audio.setVolume(21); // 0...21
+}
+
+void loop()
+{
+    audio.loop();
+}
+
+// optional
+void audio_info(const char *info){
+    Serial.println(info);
+}
+void audio_id3data(const char *info){  //id3 metadata
+    Serial.println(info);
+}
+void audio_eof_mp3(const char *info){  //end of file
+    Serial.println(info);
+}
+''''
+
+
+Breadboard
+![Breadboard](https://github.com/schreibfaul1/ESP32-audioI2S/blob/master/additional_info/Breadboard.jpg)
+Wirering
+![Wirering](https://github.com/schreibfaul1/ESP32-audioI2S/blob/master/additional_info/ESP32_I2S.JPG)
+Impuls diagram
+![Impulse diagram](https://github.com/schreibfaul1/ESP32-audioI2S/blob/master/additional_info/Impulsdiagramm.jpg)