Posted on March 28, 2018 at 10:03Hello every body im using lwip netconn tcp protocol, to send and recieve data , i have a question ,
when i connect my board ethernet cable it send and receive but when i take the cable and put back i loose my connection naturally which is normal because we need application to always research and scan if there is a connection to not make reset manually and loose data , here is my code :
void StartDefaultTask(void const * argument)
{
//struct netconn *conn, *newconn;
err_t err, accept_err;
struct netbuf *buf;
void *data;
//char *data=pvPortMalloc(2048);
//char data[100];
err_t recv_err;
uint16_t len=0;
ip_addr_t local_ip;//stm32
ip_addr_t remote_ip;//pc host
uint8_t i=0;
/* init code for LWIP */
MX_LWIP_Init();
/* USER CODE BEGIN 5 */
printf('ETHERNET STM32F429ZI lwip init complete\r\n');
char * buffer=pvPortMalloc(100);
while(gnetif.ip_addr.addr==0) osDelay(1);//wait the ip to reach the structure
printf('OUR Static ip adress:%s\r\n',ip4addr_ntoa(&gnetif.ip_addr));
local_ip =gnetif.ip_addr;
ip4addr_aton ('10.1.1.3',&remote_ip);
LWIP_UNUSED_ARG(conn);
//---------------------------------------Server---------------------------------------------//
conn=netconn_new(NETCONN_TCP);//create new network connection TCP TYPE
if (conn!=NULL)
{//new
/* Bind connection to well known port number 23 */
err = netconn_bind(conn,&local_ip,23);
if (err == ERR_OK)
{
/* Tell connection to go into listening mode. */
netconn_listen(conn);
/* Infinite loop */
while (1)
{
/* Grab new connection. */
accept_err = netconn_accept(conn, &newconn);
/* Process the new connection. */
if (accept_err == ERR_OK)/* block until we get an incoming connection */
{
while (( recv_err = netconn_recv(newconn, &buf)) == ERR_OK)
{//receive
do
{
netbuf_data(buf, &data, &len);
// netbuf_copy(buf,data,len);//not trustable much
len=netbuf_len(buf);
printf('Received %d bytes:\r\n %s\r\n',len,data);
// printf('Received %d bytes:\r\n',len);
// for (i=0;i<len;i++)
// {
// printf('%c',data[i]);
// }
sprintf(buffer,'ack from stm\n\r');
netconn_write(newconn,buffer,strlen(buffer),NETCONN_COPY);//send ack
//netconn_write(newconn, data, len, NETCONN_COPY);//send same msg to client
HAL_GPIO_TogglePin(GPIOB, GPIO_PIN_14);//blink a led to check if the prgm is keeping running
}
while (netbuf_next(buf) >= 0);
netbuf_delete(buf);//delete the recieved data
}
/* Close connection and discard connection identifier. */
// netconn_close(newconn);
// netconn_delete(newconn);
}//accept
}//while1
}//listen
else
{//bind
netconn_delete(newconn);
printf(' can not bind TCP netconn');
}
}
else//new
{
printf('can not create TCP netconn');
}
can i put this part inside of while 1 loop to check always new connection
LWIP_UNUSED_ARG(conn);
//---------------------------------------Server---------------------------------------------//
conn=netconn_new(NETCONN_TCP);//create new network connection TCP TYPE
if (conn!=NULL)
{//new
/* Bind connection to well known port number 23 */
err = netconn_bind(conn,&local_ip,23);
if (err == ERR_OK)
{
/* Tell connection to go into listening mode. */
netconn_listen(conn);
thanks
