The MicroBlaze processor has been billed as a companion co-processor or pre-processor to the PowerPC core.
Can the MicroBlaze soft processor run in a stand-alone mode, or is it dependent upon a PowerPC core?
The MicroBlaze soft processor does not have any dependency upon the PowerPC. It can run on chips that contain an embedded PowerPC and share peripherals, or it can run on a Xilinx FPGA without an embedded PowerPC processor. Both a MicroBlaze processor and a PowerPC can co-exist on the same FPGA devices.
Additionally, the MicroBlaze processor has adopted IBM's CoreConnect On-Chip Peripheral Bus (OPB) Architecture as the system bus. Therefore, any OPB peripherals designed for the MicroBlaze processor can also port to a PowerPC system.