BUS CONTROLLER FOR TRANSFERRING DATA

摘要

A host controller can be used in transferring data over a USB bus communication system in frames and micro-frames. Each data transfer is described by a packet transfer descriptor, and a packet transfer descriptor for a data transfer includes a bit map, such that data is transferred according to the packet transfer descriptor only during those micro-frames of a frame which correspond to bits of the bit map for which the bit value has been set to an active value.