I want to use the w5100 Ethernet Shield to receive ALL UDP packets sent to the shield (not just for a particular UDP port).
w5100 does not appear to support wildcard UDP receive ports.
The w5100 supposedly supports IPRAW mode sockets, and my experiments with IPRAW/ICMP (using the technique shown in section 5.2.3 of the w5100 manual and at http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1292254905) work fine and arduino can read raw ICMP packets sent to the shield.
Also setting the w5100 to MACRAW mode per the manual also works, and the arduino can read the complete raw MAC layer packet (including the IP headers etc)
But setting the w5100 to IPRAW/UDP mode does not seem to work:
when you send a UDP to the shield, it replies with port unreachable, regardless of the port number, and the shield never delivers any packets the the arduino.
Has anyone had success with IPRAW/UDP on the w5100?