I've detailed my description of this here: W5100/Ethernet cannot use socket as UDP after using it as TCP - #2 by system - Networking, Protocols, and Devices - Arduino Forum Pretty sure this is a bug. I'm not sure if it's in the library or in the W5100 itself. I've verified it on both the Uno and th…

BUG: W5100 cannot use socket as UDP after using it as TCP

SurferTim April 26, 2013, 11:40am 2

Not a bug. It works fine on IDE v1.0.4. I'm still running your code, and it is doing great, except the "No data received" message on my web browser.

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