core. The core processor operates at a maximum frequency of
800 MHz. The instruction cache is 32 Kbytes in size and is 32-way set associative. Also, the core processor includes a data cache that is 32 Kbytes and is 32-way set associative and a mini data cache that is 2 Kbytes and is 2-way set associative.An Address Translation Unit (ATU) allows PCI transactions direct access to the 80333 local memory. The Address Translation Unit supports transactions between PCI address space and80333 address space. Address translation for the ATU is controlled through programmable registers accessible from both the PCI interface and the Intel XScale® core.
The Messaging Unit (MU) provides data transfer between the 80333 and PCI-Express system. It uses interrupts to notify each system when new data arrives. The MU has four messaging mechanisms: Message Registers, Doorbell Registers, Circular Queues and Index Registers. Each allows a host processor or external PCI device and the 80333 to communicate through message passing and interrupt generation.