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7 years, 5 months ago.

Resize Ethernet MTU

Hi.

I am running into a udp packet size limit of 0x2EA = 746 bytes with my application I tried to change the MTU size in "device.ccp" with:

/* maximum transfer unit */ netif->mtu = 0x600;

and

int main() { /* Initialize lwip */ lwip_init();

Initialize UDP pcb = udp_new();

netif *netifp;

/*Initialize NetServer with static IP*/ NetServer *net = NetServer::create();

IP4_ADDR(&my_address, 192,168,0,10); IP4_ADDR(&ipmask_local, 255,255,255,0); IP4_ADDR(&ipgate_local, 192,168,0,245); IP4_ADDR(&PC_ipaddress, 192,168,0,111);

net->setUseDHCP(0); net->setIPAddr(my_address); net->setNetmask(ipmask_local); net->setGateway(ipgate_local); net->setHostname("MbedRood"); net->ready(); this will print IP

/* Change MTU size */ netifp->mtu = 1000;

/ Set mbed as receiver / udp_bind(pcb, &my_address, 5555); Receive a UDP Packet from my_address udp_recv(pcb,udp_data_recv, NULL); .... But still got the same limitation of 746 bytes.

I read about a solution for this: https://developer.mbed.org/forum/bugs-suggestions/topic/1980/ but the library isnt available anymore as it seems because the link http://mbed.org/projects/libraries-testing/svn/beta doesnt work.

Is there any other way to resize the Ethernet MTU? Or is the mentioned library available under a new link?

Thanks in advance.

Edit: Is there no mbed software engineer who can reply to this topic? It was solved years ago regarding the forum. But all links to bug fixes and libraries dont work!

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