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Arduino library for asynchronous playback of PCM/WAV files direct from SD card

Requires Arduino, SD card and output device (Speaker, Headphones, Amplifier, etc)

Features

• NEW: Up to 32khz sample rate support: Supported formats: WAV files, 8-bit, 8-32khz Sample Rate, mono

• PCM/WAV playback direct from SD card

• Asynchronous Playback: Allows code in main loop to run while audio playback occurs.

• Playback uses a single timer: Timer 1 (Uno,Mega) or Timer 3,4 or 5 (Mega)

• Quality setting: Allows 2xSample rate operation for oversampling with low sample rates

• Supported devices: Arduino Uno, Nano, Mega, etc.

• Supports complimentary output or dual speakers

• Files easily converted: Using iTunes:

  Click > Edit > Preferences > Import Settings
  Change the dropdown to WAV Encoder and Setting: Custom > 16.000kHz, 8-bit, Mono
  Right click any file in iTunes, and select "Create WAV Version"

Using Audacity:

Tracks > Stereo Track to Mono    
Project Rate (HZ) > set to 16000, 11025, or 8000    
File > Export > Save as type: Other uncompressed files > Options...    
Select WAV, Unsigned 8 bit PCM    

Then copy file to SD card using computer

Functions

TMRpcm audio;
audio.play("filename"); plays a file
audio.speakerPin = 11; set to 5,6,11 or 46 for Mega, 9 for Uno, Nano, etc
audio.disable(); disables the timer on output pin and stops the music
audio.stopPlayback(); stops the music, but leaves the timer running
audio.isPlaying();  returns 1 if music playing, 0 if not
audio.pause();  pauses/unpauses playback
audio.quality(1); for use with low sample rates
audio.volume(0); 1(up) or 0(down) to control volume
audio.setVolume(0); 0 to 7. Set volume level

Contributed HowTo: http://maxoffsky.com/maxoffsky-blog/how-to-play-wav-audio-files-with-arduino-uno-and-microsd-card/

Details at: http://tmrh20.blogspot.com

Known Limitations

• This library is very processor intensive, so code execution during playback will be slower than normal
• Processing load can be reduced by using lower quality sounds encoded at a lower sample rate (8khz minimum)
• May interfere with other libraries that rely on interrupts. The isPlaying() function can be used to prevent parallel code execution.
• Update to volume control allows greater range in low volume control, but will distort if volume too high

Installation

1. Download current package: https://github.com/TMRh20/TMRpcm/archive/master.zip
2. See the Manual Installation section at: http://arduino.cc/en/Guide/Libraries

Contributed How-To with Video: http://maxoffsky.com/maxoffsky-blog/how-to-play-wav-audio-files-with-arduino-uno-and-microsd-card/

Details at TMRh20.blogspot.com