LWIP使用dhcp无法自动获取ip

yinshiyouquan

  使用的是freertos+lwip+hal库，根据调试信息，eth hardware init sucess，sys_sem_new ok，sys_mbox_new ok，netif_set_up OK，lwip dhcp init success，结果就是获取不到ip；
，这段是开启dhcp，然后一直等待获取ip；
if(netif_is_up(&gnetif))
  {
      err = dhcp_start(&gnetif);      //开启dhcp
      if(err == ERR_OK)
        printf("lwip dhcp init success...\r\n");
      else
        printf("lwip dhcp init fail...\r\n");
      while(ip_addr_cmp(&(gnetif.ip_addr),&ipaddr))   //等待dhcp分配的ip有效
      {
        vTaskDelay(1);
    //    printf("等待分配有效ip\r\n");
      }
  }



后来我用抓包工具，抓的数据如下：Frame 2204: 342 bytes on wire (2736 bits), 342 bytes captured (2736 bits) on interface \Device\NPF_{89A318E3-CC45-4649-9EDC-36C86B8C174E}, id 0
Ethernet II, Src: 88:88:88:88:87:88 (88:88:88:88:87:88), Dst: Broadcast (ff:ff:ff:ff:ff:ff)
Internet Protocol Version 4, Src: 0.0.0.0, Dst: 255.255.255.255
User Datagram Protocol, Src Port: 68, Dst Port: 67
Dynamic Host Configuration Protocol (Discover)
    Message type: Boot Request (1)
    Hardware type: Ethernet (0x01)
    Hardware address length: 6
    Hops: 0
    Transaction ID: 0x14a67052
    Seconds elapsed: 0
    Bootp flags: 0x8000, Broadcast flag (Broadcast)
    Client IP address: 0.0.0.0
    Your (client) IP address: 0.0.0.0
    Next server IP address: 0.0.0.0
    Relay agent IP address: 0.0.0.0
    Client MAC address: 88:88:88:88:87:88 (88:88:88:88:87:88)
    Client hardware address padding: 00000000000000000000
    Server host name not given
    Boot file name not given
    Magic cookie: DHCP
    Option: (53) DHCP Message Type (Discover)
    Option: (61) Client identifier
    Option: (12) Host Name
    Option: (60) Vendor class identifier
    Option: (55) Parameter Request List
    Option: (255) End
    Padding: 0000000000
从抓包中可以看出来，mac这边出现异常，，我设置的默认mac代码如下：
HAL_StatusTypeDef Eth_Init(void)
{
  HAL_StatusTypeDef ret;

  uint8_t MACAddr[6] ;

  HAL_ETH_DeInit(&heth);

  Eth_Reset();

  ETH->DMABMR |= ETH_DMABMR_SR;

  /* Init ETH */
  MACAddr[0] = 0x02;
  MACAddr[1] = 0x00;
  MACAddr[2] = 0x00;
  MACAddr[3] = 0x00;
  MACAddr[4] = 0x02;
  MACAddr[5] = 0x00;
  heth.Instance = ETH;
  heth.Init.AutoNegotiation = ETH_AUTONEGOTIATION_ENABLE;
  heth.Init.PhyAddress = LAN8720_PHY_ADDRESS;
  heth.Init.MACAddr = &MACAddr[0];
  heth.Init.RxMode = ETH_RXINTERRUPT_MODE;  // rx mode   
  heth.Init.ChecksumMode = ETH_CHECKSUM_BY_HARDWARE;
  heth.Init.MediaInterface = ETH_MEDIA_INTERFACE_RMII;
  heth.Init.Speed = ETH_SPEED_100M;       //speed
  heth.Init.DuplexMode = ETH_MODE_FULLDUPLEX;

        /* configure ethernet peripheral (GPIOs, clocks, MAC, DMA) */
  ret = HAL_ETH_Init(&heth);
        if (ret == HAL_OK)
                printf("eth hardware init sucess...\r\n");
  else
    printf("eth hardware init faild...\r\n");

  /* Initialize Tx Descriptors list: Chain Mode */
  HAL_ETH_DMATxDescListInit(&heth, DMATxDscrTab, &Tx_Buff[0][0], ETH_TXBUFNB);

  /* Initialize Rx Descriptors list: Chain Mode  */
  HAL_ETH_DMARxDescListInit(&heth, DMARxDscrTab, &Rx_Buff[0][0], ETH_RXBUFNB);
    /* Enable MAC and DMA transmission and reception */   
  return ret;
}

因为对lwip研究实在浅薄，所以请教下大家：
1.为何发出去的discovery，mac地址会改变
2.我在接收中断中设置了打印信息，但是调试时候并没有任何中断产生，而从抓包中可以看到，路由器是有收到数据的，那为何客户端收不到数据
3.还有一个信息，关闭dhcp，使用静态测试，同样也是无法ping通

kk0668

同样遇到这样子的问题，解决了吗?