"Building a Lo-Fi Sampler with ISD1700 Technology"
OpnBeat is a simple lo-fi sampler with eight musical keys, three interface keys, and a knob. It is powered by an Arduino Nano and eight Nuvoton ISD1700s controlled over SPI by the Nano. The code, PCB, and 3D case files are all available on GitHub. The design and code are optimized to be straightforward and easy to modify, and the interface is slick.