A data processor core 10 comprising: a memory access interface portion 30 operable to perform data transfer operations between an external data source and at least one memory 120 associated with said data processor core; a data processing portion 12 operable to perform data processing operations; a read/write port 40 operable to transfer data from said processor core to at least two buses 75A, 75B said at least two buses being operable to provide data communication between said processor core 10 and said at least one memory 120, said at least one memory 120 comprising at least two portions 120A, 120B, each of said at least two buses 75A, 75B being operable to provide data access to respective ones of said at least two portions 120A, 120B; arbitration logic 110 associated with said read/write port 40; wherein said arbitration logic is operable to route a data access request requesting access of data in one portion of said at least one memory received from said memory access interface to one of said at least two buses providing access to said one portion of said at least one memory and to route a further data access request requesting access of data in a further portion of said at least one memory received from said data processing portion to a further one of said at least two buses providing access to said further portion of said at least one memory, said routing of said data access requests being performed during the same clock cycle.