该程序可使单片机实现小钢琴和播放生日快乐歌的双功能，并且用特定的两个键实现功能的切换。-With this program,MCU can be a mini piano and play a piece of music called "happy birthday to you".In addition,it can change its functions by two certain keys.

一个钢琴键盘的小程序，按键发出钢琴声，效果很不错的-piano keyboard