Abstract: The invention in its preferred embodiment involves a data producer such as a host processor that multiplexes two or more data byte streams onto a single communication link, whether serial or parallel, for transmission to a data consumer such as an ink-jet or laser printer, scanner or facsimile machine. The data are packetized with header information including a start byte, a destination channel ID byte and size byte. At the data consumer, the data under control of a state machine are header-stripped, unpacked, routed and stored in appropriate two or more ring buffers. Exception handling such as data loss or framing error recovery may be performed by the data consumer's communicating its status to the data producer or by the use of handshake lines such as READY or BUSY, rendering the invented method and apparatus compatible with unidirectional or bidirectional hardware links.

Abstract: Disclosed herein is a method of printing a document image with a host computer and an associated printer, where the printer has a printhead with a plurality of laterally-spaced dot columns. The method includes rasterizing the document image in the host computer to produce raster-formatted data representing the document image. This data is then segregated into data swaths corresponding to swaths of the printhead, and further segregating into dot-column data blocks corresponding to printhead dot columns. The dot-column data blocks are then sent to the printer in the order in which they will be processed by printhead electronics within the printer. The printer passes the dot-column data blocks to the printhead to control firing of printhead's nozzles.

Abstract: The present invention provides a method of pacing a stream of data transmitted from a data source to a buffered data destination with a determined number of available storage units, the data destinations being configured to consume data and thereby to free storage units for receipt of additional data.