PACKET BASED DATA TRANSFER SYSTEM AND METHOD FOR HOST-SLAVE INTERFACE

In a host-slave data transfer system, the slave device receives packet based data from an external device and stores the packet content in a buffer as data segments. The slave merges a plurality of data segments into data streams and transmits the data streams to the host. The host uses direct memory access (DMA) to unpack the data stream from the slave into individual data segments without memory copy. To enable the host to set up DMA, the slave transmits information regarding sizes of the data segments to the host beforehand via an outband channel, e.g. by transmitting the size information in headers and/or tailers inserted into previous data streams. The host utilizes the data segment size information to program descriptor tables, such that each descriptor in the descriptor tables causes one data segment in the data stream to be stored in the system memory of the host.