https://en.wikipedia.org/wiki/Casio_VL-1#/media/File:Casio_vl_tone.jpg

@source(Casio VL-1 @wikipedia, @date(2024-07-21)

The VL-1 was the first instrument of Casio’s VL-Tone product line, and is sometimes referred to as the VL-Tone. It combined a calculator, a monophonic synthesizer, and sequencer. Released in 1981, it was the first commercial digital synthesizer, selling for $69.95. … There were also 10 pre-loaded rhythms which utilized just three basic drum sounds. Casio internally named these sounds “Po” (30ms), “Pi” (20ms) and “Sha” (160ms). … The VL-1 was programmed by entering a number into the calculator section’s memory, then switching back to keyboard mode.