1.利用I/O口产生一定频率的方波，驱动蜂鸣器，发出不同的音调，从而演奏乐

曲（最少三首乐曲，每首不少于30秒）

2．采用LCD显示信息

3．开机时有英文欢迎提示字符，播放时显示歌曲序号（或名称）

4．可通过功能键选择乐曲，暂停，播放。

5．选作内容：显示乐曲播放时间或剩余时间-1. The use of I/O port a certain frequency square wave to drive the buzzer, to issue a different tone to play music (at least three pieces, each of the first not less than 30 seconds) 2. Using LCD display 3. Welcome to the boot prompt when the English character, the player displays the song number (or name) 4. Via the function keys to select a song, pause, play. 5. Selected as the content: show music playing time or remaining time