ETH_LWIP problem to send UDP in RTOS mode

[#1]

I got working ETH_LWIP in non RTOS mode (at least sending UDP datagrams).
on relax kit 4500

Then I tried to use in RTOS environment. I created two more threads.
If I do nothing related to ETH_LWIP, program seems to work correctly.
Both LED are blinking as expected (so both threads are running) and I can ping the relax kit.

So I tried to send UDP datagram:
1) In task "LED2_Task" I tried to use raw api, same at work for me in non RTOS environment.

void LED2_Task(void const *pvParameters)
{
  //register UDP Port
  struct udp_pcb *pcb;
  struct pbuf * pb;
  struct ip_addr dstaddr;

  IP4_ADDR(&dstaddr,192,168,0,1);
  //create socket and bind
  pcb = udp_new();
  udp_bind(pcb, IP_ADDR_ANY, DST_UDP_PORT);

  //create buffer
  pb = pbuf_alloc(PBUF_TRANSPORT, sizeof(string_to_send), PBUF_RAM);
  pb->payload = string_to_send;
  pb->len = pb->tot_len = sizeof(string_to_send);

  while(1)
  {

	DIGITAL_IO_ToggleOutput(&LED2);
	iDebugArray[2]++;
	//udp_sendto(pcb, pb, &dstaddr, DST_UDP_PORT);
	osDelay( LED2_TASK_DELAY );
  }
}

But when I uncommented line 149 in main.c following code

udp_sendto(pcb, pb, &dstaddr, DST_UDP_PORT);

threads are running for a while (according to LED blinking - maybe 5 seconds) a then stop. No UDP was sent.

2) In task "LED1_Task" I tried to use netconn api.

void LED1_Task(void const *pvParameters)
{
  struct netconn *conn;
  char msg[]="Hello Word" ;
  struct netbuf *buf;
  char * data;
  struct ip_addr dstaddr;

  iDebugArray[1]++;
  DIGITAL_IO_ToggleOutput(&LED1);



  IP4_ADDR(&dstaddr,192,168,0,1);
  //conn = netconn_new( NETCONN_UDP );
  //netconn_bind(conn, IP_ADDR_ANY, 1234 ); //local port
  //netconn_connect(conn, &dstaddr, DST_UDP_PORT );

  while(1)
  {

	//Led indication
    iDebugArray[1]++;
	DIGITAL_IO_ToggleOutput(&LED1);

	//send udp
	buf = netbuf_new();
	data =netbuf_alloc(buf, sizeof(msg));
	memcpy (data, msg, sizeof (msg));
	//netconn_send(conn, buf);
	netbuf_delete(buf); // De-allocate packet buffer

    //wait
	osDelay(LED1_TASK_DELAY);

  }
}

In this case program stopped completely before thread was executed. When I debugged the code, I find out that program never returned from function

conn = netconn_new( NETCONN_UDP );

on line 101 in main.c (see attachment).

I tried to move netconn_new( NETCONN_UDP ) to main loop before starting RTOS, but result is the same.

Is there any fatal mistake I did?
Is it available any example how to manage UDP packets in RTOS environment?

[User11187]

Hi, I have a similar problem with TCP socket.
I dont have a lot of experience with rtos, but in my case I have a stack overflow (system loops in system errore procedure), and the function never returns. Maybe it is the same for you... I think it's a configuration problem, but I don't know how to solve... I hope someone can help us.

[#3]

Hello.

I have made small research on the web and I found that all examples runs tcpip_init from thread running after osKernelStart is launched.
Something like this:

void LWIP_Init(void)
{
  struct ip_addr ipaddr;
  struct ip_addr netmask;
  struct ip_addr gw;

  /* Create tcp_ip stack thread */
  tcpip_init( NULL, NULL );

  //other init...
  .....
}

void main_task(void const *args)
{
    LWIP_Init();   
}
osThreadDef(main_task, osPriorityNormal, 1, 0);

int main(void)
{
  osKernelInitialize();
  osThreadCreate(osThread(main_task), NULL);
  osKernelStart();
}

On the contrary APP run init functions in DAVE_Init() before osKernelStart is launched.
Could be this cause of problems?

[jferreira]

Hi,

The RAW API is not meant to be used in an RTOS environment.
The netconn API (LED1_task) is working for me if you increase the default stack size from 200 to 512 bytes in the CMSIS_RTOS_RTX configuration UI.

Best regards,
Jesus

[#5]

Hi everyone,

With this project, I am able to ping the xmc4500 board.

but by using python or any other socket test app I am not able to receive the message. "Hello Word"
I am using a switch with normal Ethernet cables.
Am I doing something wrong?
did any one successfully run this code? I want to establish a send/receive UDP communication between xmc4500 and a PC.
any help is highly appreciated.

Thanks.

[#6]

almost same problem here. Not able to connect by using putty in telnet mode.

[jferreira]

Hi,

Find attached an example of a very simplistic telnet server, e.g. only help and bye commands available.

Regards,
Jesus