这是一个关于如何设计硬件电子琴的方案，里面是一个完整的程序，所用的语言是VHDL语言，能够完成硬件电子琴的基本功能。-This is a hardware keyboard on how to design the program, which is a complete program, the language used is VHDL, to complete the basic functions of the hardware keyboard.