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The MicroBlaze is a soft IP CPU core that usually runs in FPGAs by Xilinx Inc.
I do work with it often, so it was a logical choice for one of the embedded systems to run JaeOS.
The port was run on the board shown below, but really any incarnation of MicroBlaze in a Xilinx FPGA should do as hardware.
Since everything, including peripherals, is 'soft' IP running in the FPGA fabric more or less the same OS port should run on any of them.
If you rather use somethign with a higher performance you should check out FPGA options such as the Zynq with a hard CPU on them.