Abstract: A communication controller apparatus couples a device comprising a device processor to a data bus. The communication controller comprises an input/output controller coupled to the bus to receive a plurality of types of data packets. The types of data packets comprise at least one type of data packets having a high priority determined by timing criticality. The input/output controller is operable to process data packets received via the bus before providing any of the received data packets to the device processor. The communication controller comprises a high priority data path comprising a high priority data packet queue a low priority data path to the device comprising a low priority data packet queue.