TMDXEVM6678LE sending UDP message to desktop, but only one message able to send thru

/*
 * udpHello.c
 *
 * This program implements a UDP echo server, which echos back any
 * input it receives.
 *
 * Copyright (C) 2007 Texas Instruments Incorporated - http://www.ti.com/ 
 * 
 * 
 *  Redistribution and use in source and binary forms, with or without 
 *  modification, are permitted provided that the following conditions 
 *  are met:
 *
 *    Redistributions of source code must retain the above copyright 
 *    notice, this list of conditions and the following disclaimer.
 *
 *    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.
 *
 *    Neither the name of Texas Instruments Incorporated nor the names of
 *    its contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 
 *  "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 COPYRIGHT 
 *  OWNER OR CONTRIBUTORS 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.
 *
*/

#include <ti/ndk/inc/netmain.h>

SOCKET   socksend = INVALID_SOCKET;
static int PktNum = 0;
char buff1[1024] = {0};
//
// dtask_udp_hello() - UDP Echo Server Daemon Function
// (SOCK_DGRAM, port 7)
//
// Returns "1" if socket 's' is still open, and "0" if its been closed
//
int dtask_udp_hello( SOCKET s, UINT32 unused )
{
    struct sockaddr_in sin1;
    struct timeval     to;
    int                i,tmp;
    char               *pBuf;
    HANDLE             hBuffer;

    (void)unused;

    // Configure our socket timeout to be 3 seconds
    to.tv_sec  = 3;
    to.tv_usec = 0;
    setsockopt( s, SOL_SOCKET, SO_SNDTIMEO, &to, sizeof( to ) );
    setsockopt( s, SOL_SOCKET, SO_RCVTIMEO, &to, sizeof( to ) );

    for(;;)
    {
        tmp = sizeof( sin1 );
        i = (int)recvncfrom( s, (void **)&pBuf, 0, (PSA)&sin1, &tmp, &hBuffer );

        // Spit any data back out
        if( i >= 0 )
        {
            sendto( s, pBuf, i, 0, (PSA)&sin1, sizeof(sin1) );
            recvncfree( hBuffer );
        }
        else
            break;
    }

    // Since the socket is still open, return "1"
    // (we need to leave UDP sockets open)
    return(1);    
}

int sendUDPTsk()
{
    struct   sockaddr_in sinData, cliAddr;
	int sa_size1 = 0, err = 0;
	int retSize1 = 0, buff_size1 = 0, i = 0, chain = 0;

    //Allocate the file environment for this task
    fdOpenSession( TaskSelf() );

    //Initialize the socket
    socksend  = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
    if (socksend == INVALID_SOCKET)
    {
		printf(" socket(socksend) failed \n");
		return -1;
    }

    err = setsockopt( socksend, SOL_SOCKET, SO_REUSEADDR, buff1, 1472 );
	err = setsockopt( socksend, SOL_SOCKET, SO_REUSEPORT, buff1, 1472 );

    //Initialize socket address in structure
    bzero( &sinData, sizeof(struct sockaddr_in) );
    sinData.sin_family = AF_INET;
    sinData.sin_len    = sizeof( sinData );
    sinData.sin_addr.s_addr = INADDR_ANY;
    sinData.sin_port = htons(2500);

    //Bind the socket
    err = bind (socksend, (struct sockaddr *)&sinData, sizeof(sinData));
	if(err == 0)
		printf("Send-Bind operation successfully done\n");
	else
	{
		printf("Send-Bind operation failed errno= %d\n", fdError());
		return -1;
	}

    bzero( &cliAddr, sizeof(struct sockaddr_in) );
    cliAddr.sin_family = AF_INET;
    cliAddr.sin_len    = sizeof( cliAddr );
    cliAddr.sin_addr.s_addr = inet_addr("10.100.1.209"); //Target IP(PC IP address)
    cliAddr.sin_port = htons(2501);
	sa_size1 = sizeof(struct sockaddr_in);
	buff_size1 = 1024; //1472;

	TaskSleep(10000);
	buff1[0] = 48;

	while(1)
	{

	    TaskSleep(500);
		buff1[1] = i + 48;
		i++;
		chain ^= 1;
		if(chain == 0)
			memset(buff1, '1', 1024);
		else
			memset(buff1, 'A', 1024);

		retSize1 = sendto(socksend, buff1, buff_size1, 0, (struct sockaddr *)&cliAddr, sa_size1);
		if(retSize1 < 0)
			printf(" Error Sending sendto() %d \n", fdError());
        else
			printf(" %d.Send_Size = %d \n ", PktNum,retSize1);
			PktNum++;

		if(i==10)
        	i = 0;


	}


}