This video shows five examples of so called bytebeat 8bit 8KHz music, each with the C formulas used to generate the waveform and a visualization (each pixel represents one generated sample, going from bottom left upwards and right). I have created the formulas myself, even though copyright most likely can't apply to these.
<a href="//commons.wikimedia.org/wiki/User:Drummyfish" title="User:Drummyfish">Drummyfish</a>
<span class="int-own-work" lang="en">Own work</span>