uIP v0.9 TCP/IP stack with KEIL C51 * Keil Elektronik GmbH/ Keil Software Inc. C51 v7.00
compiler. This version is known to compile with the uVision2 v2.xx toolchain. * An 8051/
8052 class microcontroller with 256 bytes of internal ram (data and idata), up to 18K
bytes of FLASH or other program ROM (code), and additionally, 1K bytes of onboard or
outboard external ram (xram). * For ethernet communication: A 16 bit ISA network interface
card with a Realtek Semiconductor Co., Ltd. RTL8019AS controller chip.

移植时只要改动ETHERDEV.H中与RTL8019的相关端口... 一般采用总线或模拟时序.
还有在ETHERDEV.C有两个函数也要作相应的修改.
 static void etherdev_reg_write(unsigned char reg, unsigned char wr_data);
 static unsigned char etherdev_reg_read(unsigned char reg);
RTL8019的驱动接口，
在文件ethrdev.c中提供三个函数接口：
 void ethrdev_init()
初始化网卡芯片，使网卡进入服务状态；
 u16_t ethrdev_read()
读新的以太数据包,如果没有新数据返回0；
 void ethrdev_send()
  发送以太数据包到网络中。

演示网址: http://uip.mcu123.net/  大家可以打开这个网站看看....和下图是一样的.