UDP demo with separate ethernet MAC, detecting link state

[jdeblese]

I've been looking at the UDP demo to familiarize myself with the sc_xtcp, and using it in conjunction with a separate ethernet MAC. One problem I've run into is that the separate MAC does not pass link state information to the uIP implementation, so xtcp never emits the _IFUP or _IFDOWN events and xtcp_connect is never called.

I've looked at the documentation of sc_ethernet, but there's no function listed in the API to detect the interface state. I guess there's no problem with configuring the IP interface while the MAC is down so xtcp_connect could be called earlier, but sending and receiving will then fail, so the app should still detect the link state in some way.

Anyone familiar with sc_ethernet have an idea?