“This is a PCB version of my earlier Tiny Function Generator project based on an ATtiny85. It uses Direct Digital Synthesis to generate sine, triangle, sawtooth, square, and rectangular waves, a pulse train, and noise. The frequency can be adjusted using a rotary encoder between 1Hz and 5kHz in steps of 1Hz, and the selected waveform and frequency is displayed on an OLED display:
The original article Tiny Function Generator included seven waveforms, and the follow-up article Tiny Function Generator Sine Wave added the sine wave.”