Processor block ASIC core for embedding in an integrated circuit

A hardwired core is embedded in an integrated circuit having programmable circuitry. The hardwired core has a microprocessor; a crossbar interconnect coupled to processor local buses of the microprocessor; and a memory controller interface coupled to the crossbar interconnect. The crossbar interconnect provides pipelines for coupling the hardwired core to the programmable circuitry. The microprocessor, the crossbar interconnect, and the memory controller interface are all capable of operating at a first frequency of operation, and the memory controller interface is further capable of being set to operate at a second frequency of operation having an integer ratio with respect to the first frequency of operation. The crossbar interconnect is configured to direct transactions initiated by the microprocessor to the memory controller interface for accessing one or more memory devices coupled to the memory controller interface via a memory controller. Additional or other interfaces may be coupled to the crossbar interconnect.