A chiptune – also known as chip or 8-bit music – can best be described as a synthesized electronic track produced by vintage sound chips or emulated by more modern generations of silicon.
Typically, chiptunes consist of basic waveforms, including square waves, sawtooth or triangle waves and basic percussion. These are often generated from white noise going through an ADSR envelope, low-quality PCM samples or FM synthesis.
A talented member of the demoscene known as “dojoe” managed to rig an Atmel ATtiny9 MCU to play chiptunes – using just 1KB of flash, 32 bytes of RAM and a 16 byte register file. Dubbed Noiseplug (based on a small RCA plug), the creation has 6 pins (four usable, as two are for power) and runs at 8 MHz.