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Altera_Forum
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15 years ago

Altera TSE driver and example program for lwIP (1.3.2)

After many many requests and complaints about lack of support and/or documentation for support of lwIP for the Altera TSE, I have developed a drop-in TSE driver and example program and made this avai...
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Altera_Forum
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13 years ago

You must force an MAC resolve first, this can be accomplished by sending an UDP or ICMP packet to the address you are trying to resolve. How we are doing this is by sending ping packets to the host we want to resolve.

Here is the peace of code we use to resolve the mac address of the destination: 

	while (mac->mac == 0 && --nRetries)
	{
		// avoid context switching which could result in ARP entry cleanup and cause invalid data while memcoping
		portENTER_CRITICAL();
		// if result is positive we found a match
		if (etharp_find_addr(netif_default, &ip_req, &eth_mac, &ip_ret) >= 0)
			memcpy(mac->bytes, eth_mac->addr, MAC_ADDRESS_SIZE);
		// enable interrupts back on
		portEXIT_CRITICAL();
		// only sleep if we don't have a MAC yet
		if (mac->mac == 0) {
			lwip_ping_target_data(ipaddr, 1, 1, (u8_t*)"hello", (sizeof("hello") - 1));
			Sleep(100);
		}
	}