用keil软件打开，针对arm3嵌入式撰写的“五向键操作圆点”程序，内容涵盖timer定时器，watchdog，lcd显示屏等常用模块的使用。-Keil software open, for the use of written " Five key operation arm3 embedded dot" program, covering the contents of the timer timer, watchdog, lcd display commonly used