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Topic: Piezo trigger of wave shield playback. (Read 1 time) previous topic - next topic


I have a working wave shield and working LED/Piezo wiring patch and code for both. Being new at this, I'm having trouble figuring out how to combine the info into a working sketch where vibration triggers the piezo sensor to tell the wave shield to play the sound file. It took months to find a posting of working wave shield code. I don't know where to insert the sensor input info. Please find wave shield code below. I look forward to your comments. Thanks.


Code: [Select]
* This example plays every .WAV file it finds on the SD card in a loop
#include "WaveHC.h"
#include "WaveUtil.h"

SdReader card;    // This object holds the information for the card
FatVolume vol;    // This holds the information for the partition on the card
FatReader root;   // This holds the information for the volumes root directory
WaveHC wave;      // This is the only wave (audio) object, since we will only play one at a time

uint8_t dirLevel; // indent level for file/dir names    (for prettyprinting)
dir_t dirBuf;     // buffer for directory reads

* Define macro to put error messages in flash memory
#define error(msg) error_P(PSTR(msg))

// Function definitions (we define them here, but the code is below)
void play(FatReader &dir);

//////////////////////////////////// SETUP
void setup()
  Serial.begin(9600);           // set up Serial library at 9600 bps for debugging
  putstring_nl("\nWave test!");  // say we woke up!
  putstring("Free RAM: ");       // This can help with debugging, running out of RAM is bad

  //  if (!card.init(true)) { //play with 4 MHz spi if 8MHz isn't working for you
  if (!card.init()) {         //play with 8 MHz spi (default faster!) 
    error("Card init. failed!");  // Something went wrong, lets print out why
  // enable optimize read - some cards may timeout. Disable if you're having problems
  // Now we will look for a FAT partition!
  uint8_t part;
  for (part = 0; part < 5; part++) {   // we have up to 5 slots to look in
    if (vol.init(card, part))
      break;                           // we found one, lets bail
  if (part == 5) {                     // if we ended up not finding one  :(
    error("No valid FAT partition!");  // Something went wrong, lets print out why
  // Lets tell the user about what we found
  putstring("Using partition ");
  Serial.print(part, DEC);
  putstring(", type is FAT");
  Serial.println(vol.fatType(),DEC);     // FAT16 or FAT32?
  // Try to open the root directory
  if (!root.openRoot(vol)) {
    error("Can't open root dir!");      // Something went wrong,
  // Whew! We got past the tough parts.
  putstring_nl("Files found (* = fragmented):");

  // Print out all of the files in all the directories.

//////////////////////////////////// LOOP
void loop()

/////////////////////////////////// HELPERS
* print error message and halt
void error_P(const char *str)
  PgmPrint("Error: ");
* print error message and halt if SD I/O error, great for debugging!
void sdErrorCheck(void)
  if (!card.errorCode()) return;
  PgmPrint("\r\nSD I/O error: ");
  Serial.print(card.errorCode(), HEX);
  PgmPrint(", ");
  Serial.println(card.errorData(), HEX);
* play recursively - possible stack overflow if subdirectories too nested
void play(FatReader &dir)
  FatReader file;
  while (dir.readDir(dirBuf) > 0) {    // Read every file in the directory one at a time
    // Skip it if not a subdirectory and not a .WAV file
    if (!DIR_IS_SUBDIR(dirBuf)
         && strncmp_P((char *)&dirBuf.name[8], PSTR("WAV"), 3)) {

    Serial.println();            // clear out a new line
    for (uint8_t i = 0; i < dirLevel; i++) {
       Serial.print(' ');       // this is for prettyprinting, put spaces in front
    if (!file.open(vol, dirBuf)) {        // open the file in the directory
      error("file.open failed");          // something went wrong
    if (file.isDir()) {                   // check if we opened a new directory
      putstring("Subdir: ");
      dirLevel += 2;                      // add more spaces
      // play files in subdirectory
      play(file);                         // recursive!
      dirLevel -= 2;   
    else {
      // Aha! we found a file that isnt a directory
      putstring("Playing ");
      printEntryName(dirBuf);              // print it out
      if (!wave.create(file)) {            // Figure out, is it a WAV proper?
        putstring(" Not a valid WAV");     // ok skip it
      } else {
        Serial.println();                  // Hooray it IS a WAV proper!
        wave.play();                       // make some noise!
        uint8_t n = 0;
        while (wave.isplaying) {// playing occurs in interrupts, so we print dots in realtime
          if (!(++n % 32))Serial.println();
        sdErrorCheck();                    // everything OK?
        // if (wave.errors)Serial.println(wave.errors);     // wave decoding errors


I'm trying this same thing but with Photocell.  Did you ever get it to work?

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