说明：  开发目标：PS2键盘在ATmega16下的应用 开发环境：IAR 使用方法：将文件插入IAR工程，并在主程序中对硬件配制做相应修改
(Development objectives: PS2 keyboard ATmega16 under the application development environment: IAR Usage: Copy the file into IAR works, and in the main program in the hardware to do the preparation of consequential amendments)