Receiving IPv4 packets on an IPv6 socket works just fine but trying to reply to such a packet with sendto() causes EINVAL because lwip_sendto() rejects this case. The attached patch simply disables the check and that fixes the problem. However, I'm not sure if that has any other unintended consequen...

I needed this patch to get IPv6 working with libcoap. Without it, the IPv6 address got truncated.

Excellent! Thanks for the quick reply. Not sure how I missed that...

Do you have plans to upgrade lwip to STABLE-2_0_3_RELEASE soon so IPv6 multicast support will be available?

Thanks!

Thanks for the clarification!

Is it possible to route the ADC's reference voltage (Vref) to one of the pins? If so, how? Also, what voltage is Vref set to?

Thanks!