Plays PWM files on Arduino through piezo speaker.
Most of the results came from the following page:
http://highlowtech.org/?p=1963
I'm using the library mentioned there. count.ino is my sample sketch. As the web site mentions the audio comes out on Digital I/O pin 11. I've tested with both a piezo buzzer and a 4 ohm speaker. I'm really impressed. It does mess with some of the PWM timers so this may not be suitable for all applications.
I used Audacity to convert the sample wave files I was provided into PWM. The .h files are included in this repo.
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