Ethernut is an Open Source Hardware and Software Project for building Embedded Ethernet Devices.
For the hardware part three reference designs are currently available:
The software part is based on an Open Source implementation of a Real Time Operating System called Nut/OS and a TCP/IP protocol suite named Nut/Net.
This document is intended as a programmer's reference to the Nut/OS and Nut/Net API. It has been generated from the source code by Doxygen, a great tool created by Dimitri van Heesch.
As a first step, you may want to set up your Development Environment by following the latest version of the Ethernut Software Manual at http://www.ethernut.de/en/documents/