This paper introduces the inner-structure and using methods about the RTL8019 chip, discusses how to use the RTL8019 chip to realize the data comnunction based on TCP/IP about AVR singlechip computer.

• 介绍了RTL8019芯片的内部结构及其使用方法，详细阐述了AVR系列单片机如何通过RTL8019实现TCP/IP协议的数据通信。