ENC28J60以太网之uIP协议

        广东省电子设计大赛准备的，智能家居网关，外围单片机通信数据需要使用TCP/IP通信，故采用ENC28J60模块。

       在嵌入式系统中，以太网控制器通常也是研究热点之一，MicroChip公司的ENC28J60在嵌入式系统中应用价值较高，该芯片集成了MAC控制器和PHY，使用SPI接口，适合在引脚资源比较紧张的嵌入式系统中加入以太网连接功能，本文主要介绍了MicroChip公司的ENC28J60控制器的初始化及其编程相关的注意和要点。

        uIP作为一种广泛使用的轻量级嵌入式TCP/IP协议栈，其UDP协议的实现还不够完善，目前最新的1.0版本中仅实现了UDP客户端，尚没有实现UDP服务端。为此，对其进行了以下三方面的改进：UDP服务端口的初始化；接收到UDP客户端数据包后的端口号判断及匹配；UDP服务端发送报文后目的端口的释放。

       硬件平台：STC12C60S2+ENC28J60

 

主函数main：在函数中，对于处理应用数据的用户，对 uIP 整个流程做一个了解即可，uIP 将处理后的结果全部
都回调到uip_appcall()函数统一处理， 所以重点需要完成的工作全部在uip_appcall()函数中

/* * Copyright (c) 2001-2003, Adam Dunkels. * All rights reserved.  * * Redistribution and use in source and binary forms, with or without  * modification, are permitted provided that the following conditions  * are met:  * 1. Redistributions of source code must retain the above copyright  *    notice, this list of conditions and the following disclaimer.  * 2. Redistributions in binary form must reproduce the above copyright  *    notice, this list of conditions and the following disclaimer in the  *    documentation and/or other materials provided with the distribution.  * 3. The name of the author may not be used to endorse or promote *    products derived from this software without specific prior *    written permission.   * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.   * * This file is part of the uIP TCP/IP stack. * * $Id: main.c,v 1.10.2.1 2003/10/04 22:54:17 adam Exp $ * */#include "uip.h" #include "uip_arp.h"#include "httpd.h"//#include "telnet.h"#include "mcu_uart.h"#include "enc28j60.h"#include "tcp_server.h"#define BUF ((struct uip_eth_hdr *)&uip_buf[0])#ifndef NULL#define NULL (void *)0#endif /* NULL *//*-----------------------------------------------------------------------------------*/intmain(void){idata u8_t i, arptimer;idata u16_t j;init_uart();   //串口初始化printu("starting......\r\n");/* Initialize the device driver. */ dev_init();   //网卡初始化uip_arp_init();//ARP初始化/* Initialize the uIP TCP/IP stack. */uip_init();  //uIP协议初始化printu("uip\r\n");/* Initialize the HTTP server. *///httpd_init();tcp_server_init(); //用户自定义处，实现功能函数arptimer = 0;  //ARP缓存表更新定时器printu("ok\r\n");  while(1) {    /* Let the tapdev network device driver read an entire IP packet       into the uip_buf. If it must wait for more than 0.5 seconds, it       will return with the return value 0. If so, we know that it is       time to call upon the uip_periodic(). Otherwise, the tapdev has       received an IP packet that is to be processed by uIP. */    uip_len = dev_poll();  //查询网卡是否有包收到for(j=0;j<500;j++);   //延时，避免服务端应答过慢，造成不必要重发包/*if(uip_len > 0){printuf("--------------- uip_len = 0x%x", uip_len);printuf("%x ----------\r\n", uip_len);for(i=0;i<uip_len;i++){printuf("%x ", uip_buf[i]);if((i+1)%16==0) printu("\r\n");}printu("\r\n");}*/    if(uip_len == 0) {      for(i = 0; i < UIP_CONNS; i++) {//协议栈解析，组包，状态监测等uip_periodic(i);/* If the above function invocation resulted in data that   should be sent out on the network, the global variable   uip_len is set to a value > 0. */if(uip_len > 0) {  uip_arp_out();//有包需要发送  dev_send();}      }#if UIP_UDP      for(i = 0; i < UIP_UDP_CONNS; i++) {uip_udp_periodic(i);/* If the above function invocation resulted in data that   should be sent out on the network, the global variable   uip_len is set to a value > 0. */if(uip_len > 0) {  uip_arp_out();  dev_send();}      }#endif /* UIP_UDP */            /* Call the ARP timer function every 10 seconds. */      if(++arptimer == 20) {uip_arp_timer();   //更新ARP缓存arptimer = 0;      }          } else {//有包    处理IP包      if(BUF->type == htons(UIP_ETHTYPE_IP)) {uip_arp_ipin();uip_input();/* If the above function invocation resulted in data that   should be sent out on the network, the global variable   uip_len is set to a value > 0. */if(uip_len > 0) {  uip_arp_out();  dev_send();}      } else if(BUF->type == htons(UIP_ETHTYPE_ARP)) {//处理ARPuip_arp_arpin();/* If the above function invocation resulted in data that   should be sent out on the network, the global variable   uip_len is set to a value > 0. */if(uip_len > 0) {  dev_send();}      }    }      }  return 0;}/*-----------------------------------------------------------------------------------*/voiduip_log(char *m){//  printf("uIP log message: %s\n", m);}/*-----------------------------------------------------------------------------------*/

在tcp_server_init(); //用户自定义处，实现功能函数中

#include "example0.h"#include "example1.h"#include "tcp_server.h"//#include "httpd.h"#include "uip.h"#include "mcu_uart.h"void tcp_server_init(void) //在应用程序函数中，依靠uIP事件检测函数来决定处理的方法，//另外可以通过判断当前连接的端口号来区分处理不同的连接。{httpd_init();example0_init();   //用户自定义函数，实现某些功能的，主要监听端口example1_init();   //}void tcp_server_appcall(void) {switch(uip_conn->lport) {case HTONS(80):httpd_appcall();break;case HTONS(8000):example0_app();break;case HTONS(8001):example1_app();break;}} 

如example0_init中

void example0_init(void) {uip_listen(HTONS(8000));}

 

究竟如何调用自己编写的函数呢？在uipopt.h中，可以修改IP地址，MAC，默认网关。实现的用户自定义的函数

 

#define UIP_PINGADDRCONF 0#define UIP_IPADDR0     192 /**< The first octet of the IP address of       this uIP node, if UIP_FIXEDADDR is       1. \hideinitializer */#define UIP_IPADDR1     168 /**< The second octet of the IP address of       this uIP node, if UIP_FIXEDADDR is       1. \hideinitializer */#define UIP_IPADDR2     0   /**< The third octet of the IP address of       this uIP node, if UIP_FIXEDADDR is       1. \hideinitializer */#define UIP_IPADDR3     44  /**< The fourth octet of the IP address of       this uIP node, if UIP_FIXEDADDR is       1. \hideinitializer */#define UIP_NETMASK0    255 /**< The first octet of the netmask of       this uIP node, if UIP_FIXEDADDR is       1. \hideinitializer */#define UIP_NETMASK1    255 /**< The second octet of the netmask of       this uIP node, if UIP_FIXEDADDR is       1. \hideinitializer */#define UIP_NETMASK2    255 /**< The third octet of the netmask of       this uIP node, if UIP_FIXEDADDR is       1. \hideinitializer */#define UIP_NETMASK3    0   /**< The fourth octet of the netmask of       this uIP node, if UIP_FIXEDADDR is       1. \hideinitializer */#define UIP_DRIPADDR0   192 /**< The first octet of the IP address of       the default router, if UIP_FIXEDADDR is       1. \hideinitializer */#define UIP_DRIPADDR1   168 /**< The second octet of the IP address of       the default router, if UIP_FIXEDADDR is       1. \hideinitializer */#define UIP_DRIPADDR2   0   /**< The third octet of the IP address of       the default router, if UIP_FIXEDADDR is       1. \hideinitializer */#define UIP_DRIPADDR3   1   /**< The fourth octet of the IP address of       the default router, if UIP_FIXEDADDR is       1. \hideinitializer *//** * Specifies if the uIP ARP module should be compiled with a fixed * Ethernet MAC address or not. * * If this configuration option is 0, the macro uip_setethaddr() can * be used to specify the Ethernet address at run-time. * * \hideinitializer */#define UIP_FIXEDETHADDR 1#define UIP_ETHADDR0    0x12  /**< The first octet of the Ethernet address if UIP_FIXEDETHADDR is 1. \hideinitializer */#define UIP_ETHADDR1    0x34  /**< The second octet of the Ethernet address if UIP_FIXEDETHADDR is 1. \hideinitializer */#define UIP_ETHADDR2    0x56  /**< The third octet of the Ethernet address if UIP_FIXEDETHADDR is 1. \hideinitializer */#define UIP_ETHADDR3    0x78  /**< The fourth octet of the Ethernet address if UIP_FIXEDETHADDR is 1. \hideinitializer */#define UIP_ETHADDR4    0x90  /**< The fifth octet of the Ethernet address if UIP_FIXEDETHADDR is 1. \hideinitializer */#define UIP_ETHADDR5    0xAB  /**< The sixth octet of the Ethernet address if UIP_FIXEDETHADDR is 1. \hideinitializer */

/*为了将用户的应用程序挂接到uIP中，必须将宏UIP_APPCALL()定义成实际的应用  程序函数名，这样每当某个uIP事件发生时，内核就会调用该应用程序进行处理*/#define UIP_APPCALL     tcp_server_appcall//httpd_appcall/*

最后，如何进行测试呢：使用TCP/UDP 调试工具，上网下载的