Simple Audio Player Stuttering

Other Hardware Audio
1

Hi - New to Arduino so please bear with me. I have set up Simple Audio Player on an Arduino Due to read a short (1sec) WAV file from the SD card. Hooray - It works fine. But if I delete the while(TRUE) at the end of the sketch to try to repeat the sound, it comes out fine the first time then is all stuttery on all the subsequent plays. Any ideas as to why?

I can't seem to find any proper documentation on what the various commands (Audio.begin, Audio.prepare, Audio.write) actually do, and as I'm new to the IDE i'm not even sure where to look to inspect the code to investigate.

Any help appreciated - all I need to do is play the WAV twice every few seconds!

Regards,

Barneyward

2

You haven't posted the code, or even a link to it.

3

Ok, sorry - it's a stock Arduino example sketch.

/*
  Simple Audio Player

 Demonstrates the use of the Audio library for the Arduino Due

 Hardware required :
 * Arduino shield with a SD card on CS4
 * A sound file named "test.wav" in the root directory of the SD card
 * An audio amplifier to connect to the DAC0 and ground
 * A speaker to connect to the audio amplifier

 Original by Massimo Banzi September 20, 2012
 Modified by Scott Fitzgerald October 19, 2012
 Modified by Arturo Guadalupi December 18, 2015

 This example code is in the public domain

 http://www.arduino.cc/en/Tutorial/SimpleAudioPlayer

*/

#include <SD.h>
#include <SPI.h>
#include <Audio.h>

void setup() {
  // debug output at 9600 baud
  Serial.begin(9600);

  // setup SD-card
  Serial.print("Initializing SD card...");
  if (!SD.begin(4)) {
    Serial.println(" failed!");
    while(true);
  }
  Serial.println(" done.");
  // hi-speed SPI transfers

  // 44100kHz stereo => 88200 sample rate
  // 100 mSec of prebuffering.
  Audio.begin(88200, 100);
}

void loop() {
  int count = 0;

  // open wave file from sdcard
  File myFile = SD.open("test.wav");
  if (!myFile) {
    // if the file didn't open, print an error and stop
    Serial.println("error opening test.wav");
    while (true);
  }

  const int S = 1024; // Number of samples to read in block
  short buffer[S];

  Serial.print("Playing");
  // until the file is not finished
  while (myFile.available()) {
    // read from the file into buffer
    myFile.read(buffer, sizeof(buffer));

    // Prepare samples
    int volume = 1024;
    Audio.prepare(buffer, S, volume);
    // Feed samples to audio
    Audio.write(buffer, S);

    // Every 100 block print a '.'
    count++;
    if (count == 100) {
      Serial.print(".");
      count = 0;
    }
  }
  myFile.close();

  Serial.println("End of file. Thank you for listening!");
  while (true) ;
}