LPC1768 with LWIP drops packages makes sockets not response

Discussion created by lpcware Employee on Jun 15, 2016
Content originally posted in LPCWare by mcs-guy on Wed Jan 15 07:44:27 MST 2014
Supporty request.

I am currently implementing a Telnet server on a LPC1768. with LPCopen V1.03 and FreeRTOS.
The telnet server is working fine until the EMAC drops some packets due to heavy traffic on the ethernet link.

I can accept that some packages are dropped and data is lost but the socket locks up and never return from
       bytes_recv = lwip_recv(sockfd, &in_char, sizeof(in_char), 0);

With the EMAC-debug option enabled I can see that the pbuf are recovered.
But the recv function never return.
The lwip stacked seesm to hang up in the time out timers :
        stmf calling h=tcpip_tcp_timer arg=0
        stmf calling h=ip_reass_timer arg=0

The tcp_echo fucntion recovers fine from data loss.

I would like the lwip_recv called to return with the data send after the moment packages are lost. The missing data should not be a problem for my application.

Does somebidy know how to solve this problem?