As we know, the energy needed for sensors should be electrical. So the rst step before start to work is to convert environmental energy to electrical one. Inside the node there are dierent components for sensing the area, collecting data and

本设计采用单片机STC89C52为核心器件来设计秒表，系统实用性强、操作简单。秒表由1个4位一体共阴数码管来显示时间，显示时间为00.00~99.99秒，每秒自动加1。一个按钮实现启动/暂停功能，另一个按钮实现复位功能。按下启动/暂停键则开始计时，再按一下启动/暂停键则暂停，显示当前计时的秒数，按下复位按钮则复位，显示数值为00.00。-This design USES the microcontroller STC89C52 as the core device to design a sto