TM4C1294NCPDT: I want to add new UDP sending and receiving operations to the flash ethernet bootloader.

Hi Muneto-san,

  BOOTP is based on UDP protocol. If you look at the TivaWare Ethernet bootloader, you will find that BOOTP request is sent using uIP stack. Please refer to the bl_emac.c file in C:\ti\TivaWare_C_Series-2.2.0.295\boot_loader\bl_emac.c where uip_udp_send(sizeof(tBOOTPPacket)) is the function to send the BOOTP request. The uIP stack is an open-source implementation of the TCP/IP network protocol stack intended for its small memory footprint. The uIP stack can be found in C:\ti\TivaWare_C_Series-2.2.0.295\third_party\uip-1.0\uip. You can reference how uip_udp_send() is used to implement your application specific requirements in your custom bootloader. 

static void
SendBOOTPRequest(void)
{
    uint8_t *pui8Packet = (uint8_t *)uip_appdata;
    tBOOTPPacket *psBOOTP = (tBOOTPPacket *)uip_appdata;
    uint32_t ui32Idx;

    //
    // Zero fill the BOOTP request packet.
    //
    for(ui32Idx = 0; ui32Idx < sizeof(tBOOTPPacket); ui32Idx++)
    {
        pui8Packet[ui32Idx] = 0;
    }

    //
    // Construct a BOOTP request.
    //
    psBOOTP->ui8Op = BOOTP_REQUEST;

    //
    // Set the hardware type to Ethernet.
    //
    psBOOTP->ui8HType = 0x01;

    //
    // Set the hardware address length to 6.
    //
    psBOOTP->ui8HLen = 0x06;

    //
    // Choose a random number for the transaction ID.
    //
    psBOOTP->ui32XID = g_ui32XID = RandomNumber();

    //
    // Set the number of seconds since we started.
    //
    psBOOTP->ui16Secs = HTONS(g_ui32Ticks / SYSTICKHZ);

    //
    // Fill in the Ethernet MAC address.
    //
    for(ui32Idx = 0; ui32Idx < 6; ui32Idx++)
    {
        psBOOTP->pui8CHAddr[ui32Idx] = g_sMACAddr.addr[ui32Idx];
    }

    //
    // Set the server name if defined.
    //
#ifdef ENET_BOOTP_SERVER
    for(ui32Idx = 0;
        (psBOOTP->pcSName[ui32Idx] = ENET_BOOTP_SERVER[ui32Idx]) != 0;
        ui32Idx++)
    {
    }
#endif

    //
    // Send the BOOTP request packet.
    //
    uip_udp_send(sizeof(tBOOTPPacket));
}