AMBI sensor and wave shield

Im sure this is really easy but I’m new :wink:

Essentially what I want to do is have my wave shield play a song when the value from the AMBI sensor ( hooked up to analog pin 0 ) reaches a certain brightness. Heres the code I’ve got running the Waveshield:

#include <FatReader.h>
#include <SdReader.h>
#include <avr/pgmspace.h>
#include "WaveUtil.h"
#include "WaveHC.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 filesystem on the card

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

WaveHC wave;      // This is the only wave (audio) object, since we will only play one at a time

int LDR = 0; // LDR Pin
int val = 0;       // variable to store the value coming from the sensor



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

void setup() {
  Serial.begin(9600);           // set up Serial library at 9600 bps for debugging
  pinMode(LDR, INPUT);       // declare the LDR as an INPUT
  putstring_nl("\nWave test!");  // say we woke up!
  
  putstring("Free RAM: ");       // This can help with debugging, running out of RAM is bad
  Serial.println(freeRam());  
 
  // Set the output pins for the DAC control. This pins are defined in the library
  pinMode(2, OUTPUT);
  pinMode(3, OUTPUT);
  pinMode(4, OUTPUT);
  pinMode(5, OUTPUT);
  
  //  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!)  
    putstring_nl("Card init. failed!");  // Something went wrong, lets print out why
    sdErrorCheck();
    while(1);                            // then 'halt' - do nothing!
  }
  
  // enable optimize read - some cards may timeout. Disable if you're having problems
  card.partialBlockRead(true);
  
  // 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  :(
    putstring_nl("No valid FAT partition!");
    sdErrorCheck();      // Something went wrong, lets print out why
    while(1);                            // then 'halt' - do nothing!
  }
  
  // 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)) {
    putstring_nl("Can't open root dir!"); // Something went wrong,
    while(1);                             // then 'halt' - do nothing!
  }
  
  // Whew! We got past the tough parts.
  putstring_nl("Files found:");
  dirLevel = 0;
  // Print out all of the files in all the directories.
  lsR(root);
}

//////////////////////////////////// LOOP
void loop() { 
  root.rewind();
  play(root);
  val = analogRead(LDR);       // read the value from the sensor
}

/////////////////////////////////// HELPERS

// this handy function will return the number of bytes currently free in RAM, great for debugging!   
int freeRam(void)
{
  extern int  __bss_end; 
  extern int  *__brkval; 
  int free_memory; 
  if((int)__brkval == 0) {
    free_memory = ((int)&free_memory) - ((int)&__bss_end); 
  }
  else {
    free_memory = ((int)&free_memory) - ((int)__brkval); 
  }
  return free_memory; 
} 

/*
 * print error message and halt if SD I/O error, great for debugging!
 */
void sdErrorCheck(void)
{
  if (!card.errorCode()) return;
  putstring("\n\rSD I/O error: ");
  Serial.print(card.errorCode(), HEX);
  putstring(", ");
  Serial.println(card.errorData(), HEX);
  while(1);
}
/*
 * print dir_t name field. The output is 8.3 format, so like SOUND.WAV or FILENAME.DAT
 */
void printName(dir_t &dir)
{
  for (uint8_t i = 0; i < 11; i++) {     // 8.3 format has 8+3 = 11 letters in it
    if (dir.name[i] == ' ')
        continue;         // dont print any spaces in the name
    if (i == 8) 
        Serial.print('.');           // after the 8th letter, place a dot
    Serial.print(dir.name[i]);      // print the n'th digit
  }
  if (DIR_IS_SUBDIR(dir)) 
    Serial.print('/');       // directories get a / at the end
}
/*
 * list recursively - possible stack overflow if subdirectories too nested
 */
void lsR(FatReader &d)
{
  int8_t r;                     // indicates the level of recursion
  
  while ((r = d.readDir(dirBuf)) > 0) {     // read the next file in the directory 
    // skip subdirs . and ..
    if (dirBuf.name[0] == '.') 
      continue;
    
    for (uint8_t i = 0; i < dirLevel; i++) 
      Serial.print(' ');        // this is for prettyprinting, put spaces in front
    printName(dirBuf);          // print the name of the file we just found
    Serial.println();           // and a new line
    
    if (DIR_IS_SUBDIR(dirBuf)) {   // we will recurse on any direcory
      FatReader s;                 // make a new directory object to hold information
      dirLevel += 2;               // indent 2 spaces for future prints
      if (s.open(vol, dirBuf)) 
        lsR(s);                    // list all the files in this directory now!
      dirLevel -=2;                // remove the extra indentation
    }
  }
  sdErrorCheck();                  // are we doign OK?
}
/*
 * 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 . and .. directories
    if (dirBuf.name[0] == '.') 
      continue;
    
    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
      Serial.println("file.open failed");  // something went wrong :(
      while(1);                            // halt
    }
    
    if (file.isDir()) {                    // check if we opened a new directory
      putstring("Subdir: ");
      printName(dirBuf);
      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 "); printName(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!
       
        while (wave.isplaying) {           // playing occurs in interrupts, so we print dots in realtime
          putstring(".");
          delay(100);
        }
        sdErrorCheck();                    // everything OK?
//        if (wave.errors)Serial.println(wave.errors);     // wave decoding errors
      }
    }
  }
}

If someone could help me out that would be great :slight_smile:

Not tested:

  val = analogRead(LDR);       // read the value from the sensor
  if ( val > 500 ) play(root);

Doesn’t work… maybe I am inserting the code into the wrong part of the program?

It should be in the loop:

void loop() { 
  root.rewind();
//  play(root);
  val = analogRead(LDR);       // read the value from the sensor
if ( val > 500 ) play(root);
}

Do you know what value you are reading from light sensor? (500 just an example). It would make sense to run simple scketch first, which is only reading ambient light and print out on serial monitor, so you could confirm it's level varying , there is a min and max. Look into examples of arduino IDE how to do it.

Seems to be working now, thanks for your help!