Introduction - If you have any usage issues, please Google them yourself
The main system of musical performance circuit consists of 4 modules: FDIV, CODE_DATA, F_CODE and DRIVER. Wherein, the module U1 (FDIV) is a frequency division function to divide the input 6MHz clock signal into 1MHZ and 4Hz signals. U2 (CODE_DATA) resembles the fingers of a piano player; the module U3 (F_CODE) resembles a keyboard; the module U4 (DRIVER) is similar to a string or tone sounder.