Atmega128单片机通过DHCP和TFTP实现自更新的代码，实现了TCP/IP协议栈-Atmega128 microcontroller through DHCP and TFTP to achieve self-updating code to achieve the TCP/IP protocol stack

驱动w5100实现dhcp功能的代码，并附有如何实现dhcp功能的说明-Driver w5100 achieve dhcp function code, together with instructions on how to achieve dhcp function