void IP_ARP(void)     //ARP數(shù)據(jù)處理
{
   UINT i,Len;
   for (i=0;i<6;i++)
      MAC_O_Addr[i]=Receive_Buffer[i+6];  //保存外部MAC地址
   for (i=0;i<4;i++)
      IP_O_Addr[i]=Receive_Buffer[i+22+6];  //保存外部IP地址

   printf("外部MAC地址 ");
   for(i=0;i<6;i++)
      printf("%2x ",MAC_O_Addr[i]);
   printf("\n");
   printf("外部ip地址 ");
   for(i=0;i<4;i++)
      printf("%d.",IP_O_Addr[i]);
   printf("\n\n");

   //開始拼接ARP返回包
   HEAD_Ethernet();        //以太網(wǎng)頭
   Len=Start_ARP;
   Send_Buffer[Len++]=0x00;               //硬件類型，0x0001 MAC地址
   Send_Buffer[Len++]=0x01;
   Send_Buffer[Len++]=0x08;               //協(xié)議類型，0x0800 IP地址
   Send_Buffer[Len++]=0x00;
   Send_Buffer[Len++]=6;                  //硬件地址長度，6  MAC地址占用字節(jié)數(shù)
   Send_Buffer[Len++]=4;                  //協(xié)議地址長度，4  IP地址占用字節(jié)數(shù)
   Send_Buffer[Len++]=0;                  //OP（操作類型），2  ARP應(yīng)答
   Send_Buffer[Len++]=2;
   for (i=0;i<6;i++)
      Send_Buffer[Len++]=MAC_Addr[i];  //本地MAC地址
   for (i=0;i<4;i++)
      Send_Buffer[Len++]=IP_Addr[i];  //本地IP地址
   for (i=0;i<6;i++)
      Send_Buffer[Len++]=MAC_O_Addr[i];  //外部MAC地址
   for (i=0;i<4;i++)
      Send_Buffer[Len++]=IP_O_Addr[i];  //外部IP地址
   while(Len<64)
      Send_Buffer[Len++]=0x00;    //小于64字節(jié)的部分用0填充

   NET_Send_Packet(Send_Buffer,Len);  //發(fā)送數(shù)據(jù)包
}