System for transferring data between processors via dual buffers within

Abstract

A method and apparatus for the enhancing efficiency of a data processing system which includes a host microprocessor, a system memory, and a graphics adapter for producing an enhanced graphics display. The graphics adapter is coupled to the data processing system by a bus and includes a video memory and an adapter microprocessor, wherein the adapter microprocessor is less powerful than the host microprocessor in the data processing system. The method and apparatus of the present invention includes the establishment of a stage buffer from a portion of the system memory with the stage buffer, including at least two buffer sections. A first portion of data is transferred from the system memory into a first buffer section. Next, a second portion of data is transferred from the system memory into a second buffer section, while the adapter microprocessor is simultaneously retrieving the first portion of data from the first buffer section and transferring that first portion of data across the bus to the video memory, wherein host microprocessor is available to perform other tasks. When the adapter microprocessor has transferred the data to the video memory from the first buffer section, the host microprocessor fills the first buffer section with more data, while the adapter microprocessor retrieves data from the second buffer section. This process continues until all the data has been transferred.