SinePlayer
This small project demonstrate the Tiny family high speed PWM capabilities to produce a sinewave output. It was also incorporated functions to play Piano Key Tones using sinewave waveform, as a smooth and clean sound as the ones produced by cords.
The sinewaves produces are better in low frequencies. The high frequency keys need to jump over a larger byte quantity in the sine table, to be able to produce the correct frequency, it generates a high frequency component over the sinewave, and it may be noticeable on the sound speaker.The circuit consists of ATTiny13 and RC low-pass filter. 
   SinePlayer
Visit SinePlayer website
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