Simple example-Arduino playback module

After discoraged by carelessly burned one SD card in the Waveshield, I became more precise when trying to link two pins together. Once pin connection can be fixed, programming for Arduino can be interesting.

Here's the program I've modified for playback different sound sample based on any switches that can connect analog-in0 and gnd.

#include
#include
#include
#include "WaveUtil.h"
#include "WaveHC.h"

#define SWITCH_PIN 14

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

// 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

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);

/*add by Iris*/
// pin13 LED
pinMode(13, OUTPUT);
// enable pull-up resistors on switch pins (analog inputs)
digitalWrite(SWITCH_PIN, HIGH);
/*end*/

// 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);
}

/////////////////////////////////// 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?
}

/*add by Iris*/
bool read_switch()
{
return digitalRead(SWITCH_PIN);
}
/*end*/

/*
* 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
/*add by Iris*/
/*sleep until switch pressed, low */
while(read_switch()) delay(10);
/*end*/

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);
/*add by Iris*/
if(read_switch())
{
wave.stop();
break;
}
/*en*/
}

sdErrorCheck(); // everything OK?
// if (wave.errors)Serial.println(wave.errors); // wave decoding errors
}
}
}
}