A Pluto FPGA board, a speaker and a 1KΩ resistor are used for this project.
A more formal representation looks like this:
The oscillator provides a fixed frequency to the FPGA. The FPGA divides the fixed frequency to drive an IO. The IO is connected to a speaker through the 1KΩ resistor. By changing the IO frequency, the FPGA produces different sounds.
The music box project is split into four parts: