Xerox Corporation

Warren M Sterling

David H Hartke

William D Turner

Wilbur E DuVall

Jack E Shemer

David Cronshaw

James R Keddy

An autonomous processor for displaying on a video tube both text characters and facsimile data. To conserve memory space the facsimile data is stored in compressed form and is decompressed or unfolded in synchronism with the vertical and horizontal deflections in the video tube. Similarly the text characters are stored in coded form, together with interspaced commands, both inscribed in a list memory. Each character code in the list then selects an appropriate dot matrix from a font memory which also contains displacement data. Selected lines of the font dot matrices are then addressed by row coordinates to form a horizontal video signal, which is accumulated in a ping pong buffer concurrently unloading into a video register. This same video register merges the facsimile data which is concurrently unfolded.

Fax processor

A distributed function processing system utilizing a conventional microprocessor operated as a text processor in combination with a plurality of other autonomous processing devices arranged to operate in a coherent processing system. One of the autonomous processors which is a memory control processor serves to periodically overlay a random access accelerator memory with the contents of a main memory system and concurrently resolves conflicts among various other autonomous memory service requests. This processor, therefore, accommodates the data rates of the main memory. The other processor is a display processor which generates signals to a video display system to provide a visual interface to the user and is therefore tied to the video rate. Accordingly, the processing burden is distributed within processors entailing differing rates operating autonomously. The memory control processor resolves and accommodates all of the memory service requests in the system and also performs control operations to support high speed I/O devices. Logic is provided to handle the other interrupts. Also, there is page mapping for context switching of a reference page and repeating logic for decoupling this processor from the other processors. This arrangement allows convenient expansion into plural work stations each sharing a common memory.

Soft display word processing system with multiple autonomous processors

Growing community of inventors

Hermosa Beach, CA, United States of America

Warren M Sterling