Quote:
the j-core processor, a clean-room open source processor and SOC design using the SuperH instruction set, implemented in VHDL and available royalty and patent free under a BSD license
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The j2 is a nommu processor because sh2 (the processor in the Sega Saturn game console) was, and the last sh2 patent expired in October 2014
There's a video: 
Building a CPU from Scratch: jcore Design Walkthrough by Rob Landley & Jeff DionneFor more on j-core CPUs, see 
http://j-core.org/ and, for Linux without an MMU, 
http://nommu.org/