目前比较流行的一种通信协议------I2C总线协议（AT2402），里面包含此协议的通信规则，驱动lcd1602显示时钟，并且在断电后依然保存数据,省去再调烦恼。-A current popular communication protocols------ I2C bus protocol (AT2402), which contains the rules of this agreement, communication, drive lcd1602 show the clock, and