Update... an Adafruit dependency Adafruit_SPIFlash_FatFs.h is not longer available... look to some folks that have forked this repo like gambalunga who got it working using the updated Adafruit library.
This polyphonic library allows you to play WAV files from SPI Flash and SD card to the 10bit DAC of a SAMD21 (Pin A0 on many boards).
Plays up to ~4 WAV files simultaneously.
Adafruit has a nice tutorial on how to connect the pin to a 1/8" audio jack. The hookup instructions are here (ignore the circiut python example as this library is for an Arduino sketch).
The 8bit sound quality is medium quality. I was able to get up to 44.1khz using SPI flash on the Adafruit M0 boards. The quality needed to be reduced to ~22khz when playing from the SD card.
It all sounds fairly marginal at 8bit. Until there is a library with 16bit DMA output, I recommend going with a Teensy or a peripherial codec to do the heavy lifting of playing quality audio.... but hey this all sounds better than the Arduino UNO.
The following Adafruit Express boards have onboard FLASH where you can store up to 2MB of sound ~30-60seconds. This includes:
- Itsybits M0 Express (tested)
- Adafruit Metro M0 Express
- Trinket M0 Express and Gemma Express no SPI Flash so SD card playing only.
- Adafruit M4 Express boards with the SAMD51? should work
Read this great description in the Adafruit tutorial for getting the WAV files onto your Adafruit M0 Express board https://learn.adafruit.com/introducing-itsy-bitsy-m0?view=all#using-spi-flash Thanks to Tony Dicola and Adafruit for making this so easy!
For the SD card example, these lines need to be edited in SamdAudio.cpp
To revert back to playing WAV files from flash storage example goes like this in SamdAudio.cpp:
Flash example included in the examples folder. See also SD Card Example:
/*
Audio player, non blocking.
read 8bit mono .wav file, up to 4 channels
use Audacity to convert your audio file
Author : AloyseTech
03/17/19: https://github.com/hydronics2/SamdAudio
updated to work with Adafruit Qaud Flash memory boards.
This will work with any SAMD21 chip using SPI flash with a little tinkering
- itsyBitsy M0 Express,
- Feather M0 Express,
- probalby M4 of abovev and trinkets
Read this great description in the Adafruit tutorial for getting the WAV files onto your Adafruit M0 Express board
https://learn.adafruit.com/introducing-itsy-bitsy-m0?view=all#using-spi-flash
Thanks to Tondy Dicola and Adafruit for making this so easy!
if the sketch compiles and Initializes Audio player, but no sound, look in SamdAudio.cpp and umcomment these!
- #include <Adafruit_SPIFlash.h>
- #include <Adafruit_SPIFlash_FatFs.h>
- extern Adafruit_W25Q16BV_FatFs memory;
*/
#include <SPI.h>
#include <Adafruit_SPIFlash.h>
#include <Adafruit_SPIFlash_FatFs.h>
#define FLASH_TYPE SPIFLASHTYPE_W25Q16BV // Flash chip type.
// If you change this be
// sure to change the fatfs
// object type below to match.
#define FLASH_SS SS1 // Flash chip SS pin.
#define FLASH_SPI_PORT SPI1 // What SPI port is Flash on?
Adafruit_SPIFlash flash(FLASH_SS, &FLASH_SPI_PORT); // Use hardware SPI
// Finally create an Adafruit_M0_Express_CircuitPython object which gives
// an SD card-like interface to interacting with files stored in CircuitPython's
// flash filesystem.
Adafruit_W25Q16BV_FatFs memory(flash);
#include <SamdAudio.h> //
SamdAudio AudioPlayer;
#define NUM_AUDIO_CHANNELS 4 //could be 1,2 or 4 for sound
#define AUDIO_BUFFER_SIZE 1024 //512 works fine for 22.05kh, use 1024 for 32khz and 44.1khz
//indicate sample rate here (use audacity to convert your wav)
const unsigned int sampleRate = 32000; //hz
//your wav file
const char *filename0 = "poem8bit_32khz.wav";
const char *filename1 = "sfx1_8bit_32khz.wav";
const char *filename2 = "sfx2_8bit_32khz.wav";
const char *filename3 = "sfx3_8bit_32khz.wav";
const char *filename4 = "sfx4_8bit_32khz.wav";
void setup()
{
delay(10);
Serial.begin(115200);
while (!Serial); // open the serial to start!
// Initialize flash library and check its chip ID.
if (!flash.begin(FLASH_TYPE))
{
Serial.println("Error, failed to initialize flash chip!");
while(1);
}
Serial.print("Flash chip JEDEC ID: 0x"); Serial.println(flash.GetJEDECID(), HEX);
// First call begin to mount the filesystem. Check that it returns true
// to make sure the filesystem was mounted.
if (!memory.begin())
{
Serial.println("Error, failed to mount filesystem!");
while(1);
}
Serial.println("Mounted filesystem!");
Serial.print("Initializing Audio Player...");
if (AudioPlayer.begin(sampleRate, NUM_AUDIO_CHANNELS, AUDIO_BUFFER_SIZE) == -1)
{
Serial.println(" failed!");
return;
}
Serial.println(" done.");
AudioPlayer.play(filename0, 1);
Serial.println("Playing file.....");
}
void loop()
{
if (Serial.available())
{
char c = Serial.read();
Serial.println(c); //for debug
if ( c == 'o')
{
AudioPlayer.play(filename1, 0); //playing file on channel 0
Serial.println("playing audio file on channel 0");
}
if ( c == 'p')
{
AudioPlayer.play(filename2, 1); //playing file on channel 1
Serial.println("playing audio file on channel 1");
}
if ( c == 'k')
{
AudioPlayer.play(filename3, 2); //playing file on channel 2
Serial.println("playing audio file on channel 2");
}
if ( c == 'l')
{
AudioPlayer.play(filename4, 3); //playing file on channel 3
Serial.println("playing audio file on channel 3");
}
}
}