Abstract: The present invention provides a system and method for simultaneously controlling a plurality of print engines connected together (in series, in parallel or otherwise) that facilitates electronic stitching between the print engines. More specifically, the present invention provides a system and method for synchronizing the pixel deposition frequencies and the drive mechanisms between the various inter-connected print engines so as to eliminate synchronization between the print engines.

Abstract: An electronic image registration system for a high-speed raster printer controller includes dedicated hardware for performing run-time registration, in both the horizontal and vertical directions, on a continuous stream of rasterized bit-map data generated by the rendering units of the raster printer controller. The registration takes place in hardware, between the rendering section of the controller and the print engine, thus allowing the registration to be performed in real-time without slowing the controller's processing speeds. The dedicated run-time electronic-image registration hardware for the vertical registration of the image includes a vertical holding register and a vertical counter. The vertical holding register is loaded by a CPU and indicates the magnitude of the vertical registration, which in turn indicates a length of delay in scan-line units before the start of the page-map's print cycle after seeing a “top-of-form” signal from the print engine.

Abstract: A method for controlling a printer having a plurality of print engines and a print engine controller includes the steps of: (a) coupling each of the print engines to a corresponding print engine communication device; (b) coupling together the print engine communication devices and the print engine controller in a daisy chain configuration with a serial data link, the data-output port of the printer controller being directly coupled by the serial data link to a first one of the print engine communication devices and the data-input port of the printer controller being directly coupled by the serial data link to a last one of the print engine communication devices; (c) embedding commands and data in a data stream by the printer controller and transmitting the data stream on the serial data link to the first print engine communication device by the printer controller; (d) relaying the data stream from the first print engine communication device back to the serial data link by the first print engine controller; (e

Abstract: A method for generating a stroke frequency signal on a plurality of ink jet printheads arranged along a moving web includes the steps of: (a) coupling the raster printer controller to the plurality of printheads with a plurality of data links in a daisy-chain configuration, where the printer controller is at the beginning of the daisy-chain; (b) embedding a web velocity signal indicative of web velocity in data, by the printer controller; (c) communicating the data with the embedded velocity signal to each of the printheads by transmitting the data with the embedded velocity signal onto the daisy-chain; (d) each of the printheads deriving the web velocity signal from the data received from the daisy-chain by each of the printheads; and (e) generating a stroke frequency signal from the web velocity signal by each of the printheads.

Abstract: The method for synchronizing the plurality of piezoelectric crystals on a corresponding plurality of ink jet printheads comprises the steps of: (a) coupling the plurality of printheads together in a daisy-chain configuration, (b) embedding a first clock signal in data; (c) transmitting the data to the printheads on the daisy-chain; (d) each of the printheads receiving the data; (e) each of the printheads deriving a second clock signal from the data received, which is directly proportional to the first clock signal; and (f) each of the printheads driving its corresponding piezoelectric crystal with the second clock signal. Accordingly, all of the piezoelectric crystal clock sources will be synchronized in frequency with each other, eliminating beat frequency drift errors between the printheads.

Abstract: A printing system includes a plurality of print engines; a raster printer controller having a processor for generating the rasterized bitmap data; and a plurality of print engine communication devices, where each of the print engine communication devices are coupled to a corresponding one of the print engines to provide the rasterized bitmap data to the corresponding print engine. The print engine communication devices are coupled together with the raster printer controller in a daisy chain configuration by a data link. Each of the print engine communication devices includes a message processing circuit that is adapted to monitor data received from raster printer controller, execute commands embedded in data received, update a bitmap data memory storage buffer in the print engine communication device with rasterized bitmap data embedded in the data received from the raster printer controller.

Abstract: A digital high-speed printing system architecture for processing contiguous raster-image data blocks for transmission to a marking engine, comprises a central processing unit ("CPU") and at least one video RAM device. Each video RAM device includes a dynamic band RAM, a serial access memory, a random access port for transmitting and receiving image data blocks to and from the dynamic band RAM, and a serial port for transmitting and receiving image data blocks to and from the serial access memory. The video RAM devices perform bi-directional image data block transfers between the dynamic band RAM and the serial access memory. Furthermore, the video RAM devices transfer image data blocks to and from the serial access port, and simultaneously transfer of image data blocks to and from the random access port.

Abstract: An on-board diagnostic system which comprises dedicated hardware for performing run-time diagnostics on a computer board having several functional sections. The diagnostic system utilizes a serial token ring network, which preferably has a software-independent, hardware core, comprising a non-intelligent master device and a plurality of non-intelligent slave devices. The master and slave devices are all interconnected via a dedicated serial data bus which operates independently of the on-board CPUs and on-board CPU buses. Each slave device is responsible for monitoring a particular section of the computer board. The master device polls each slave device by activating a corresponding token line on each slave device for a predetermined period of time, one at a time, until the master device is alerted by a slave device that a change of state has occurred in the status signals of that particular section.

Abstract: An electronic image registration method for use with a high-speed raster printer controller provides run-time registration of an image which is defined by a continuous stream of rasterized bit-map data. The method includes the steps of: (a) detecting a misalignment of the image with respect to a form, and producing a registration value in response to the detected misalignment; (b) acquiring a present block of the bit-map data from the stream; (c) shifting the present block of the bit-map data a number of bits according to a shift count generated from the registration value produced in step (a) to create a present contiguous set of shifted bit-map data bits and a present contiguous set of spill-over bit-map data bits; (d) storing the present set of spill-over bits; (e) combining the present set of shifted bits with a previous contiguous set of spill-over bit-map data bits to create a present registered block of bit-map data; and (e) dispatching the present registered block to a print engine.

Abstract: A method and architecture is provided for merging a variable image data bitmap into a template image and for transmitting the merged image to a print engine; where the template image is defined by rendering commands derived from a page description language, and the variable image data bitmap is taken from a list of the variable data bitmaps. The method comprises the steps of continuously rendering template image data bands, in accordance with the set of rendering commands, and transferring the template image data bands to a mass storage. Once the entire template image is stored in the mass storage, the variable image data bitmap is merged with the template image bitmap and sent to the print engine by continuously loading template image data bands from the mass storage, logically mapping the variable image data bitmap into the template image data bands to produce merged image data bands, and dispatching the merged image data bands to the print engine.