[Solved] W5500 ignores "Wi-Fi" ARP request with padding


I’ve noticed that if I use the scheme PC-Ethernet-Router-Ethernet-W5500 (I) all comunication is OK, but on using PC-WiFi-Router-Ethernet-W5500 (II) all fails, even ping. Wireshark analyse showed, that in scheme II ARP packet has 18 padding bytes, and w5500 ignored these packets. I tried 2 development boards with w5500, with the same result. Please, advice what to do for getting reply for type II packets. Wireshark log and screenshots included.

packets capture.zip (707 Bytes)

Change MAC address of the device from 03:08:DC:00:AB:CD to, for example, 00:08:DC:00:AB:CD, and try again.

It works! Thanks :slight_smile:

Conclusion - bits 0 and 1 of the MSB of MAC address should be used with caution as they are reserved for special purposes: en.wikipedia.org/wiki/MAC_addre … _vs._local