1.通过本例程了解 DLASS18b20的基本原理和使用 ,理解并掌握18B20驱动程序的编写　　

2.了解掌握I2C总线接口的工作原理及一般编程方法。 　　　　

插上18B20 观察数码管的实际温度显示-1. DLASS18b20 through this routine to understand the basic principles and use the driver to understand and master the preparation of 18B20 2. Understand the working principle of I2C bus interface and general programming. Plug 18B20 observe the actual temperature digital display