Abstract: A USB host/client system includes a USB host device, a USB client device connected via a USB cable to the USB host device, and a power supply unit remote from the USB host device for powering the USB host device through the USB cable connecting the USB client device to the USB host device. The USB host device can have means for communicating with a computer while the USB host device is connected to a USB client device, and/or the power supply unit supplies sufficient power for all normal operations of the USB host device.

Abstract: A method for dynamically compensating for a faulty pixel in a scan line of a scanner having an image sensor with a plurality of sensor pixels includes generating digitized scan data; processing the digitized scan data to compensate for any faulty pixels of the plurality of sensor pixels to form compensated scan data; processing the compensated scan data to apply offset and gain correction to the compensated scan data to form calibrated scan data; processing the calibrated scan data to adjust the calibrated scan data to compensate for human visual perception to form final scan data; and storing the final scan data in a scanner image memory.

Abstract: Printer (1) is provided with a mode to edit and print forms without reference to or interruption of a host computer and with immediate printing of one or more of the forms. Page data for the forms is preferably stored in flash memory (21) in a high level printer language. Preferably, at initiation of the forms mode at least the first listed document is immediately prepared by the control data processor (17) of the printer in bit mapped form for printing. Documents can be listed on the control panel by name for ready selection for printing.

Abstract: A method of transforming a n-bit data packet to a m-bit data packet with a lookup table. The lookup table includes at least one entry data packet and at least one respective delta value associated with each entry data packet. The method includes the acts of receiving an input data packet having n-bits, indexing the lookup table with at least a portion of the input data packet to obtain one of the at least one entry data packet, and decompressing the obtained entry data packet with the at least one respective delta value associated with the obtained entry data packet, thereby resulting in an output data packet having m-bits. The decompressing act includes using a portion of the input data packet to determine the number of delta values called for decompressing the obtained entry data packet. The method can be used in, for example, an image processor.

Abstract: Error diffusion is performed upon input image data. In one aspect, multiple error diffusion processing elements perform error diffusion on a selected pixel in parallel. In another aspect, the error diffusion logic is integrally formed with a fast local memory in the same electronic device, such as an ASIC. The error data produced by the error diffusion logic for a pixel is buffered in the fast local memory until it is to be used by the error diffusion logic on other pixels. In still another aspect, a first-in-first-out (FIFO) buffer regulates or buffers the color image data between the output of a color conversion system, such as a colorant lookup table, and the input an error diffusion processing element. In yet another aspect, the error diffusion logic has tagging logic that produces and stores an indicator, either in the output data stream itself or in a separate area, to indicate whether a raster contains printable data.

Abstract: A method for dynamically compensating for a faulty pixel in a scan line of a scanner having an image sensor with a plurality of sensor pixels includes generating digitized scan data; processing the digitized scan data to compensate for any faulty pixels of the plurality of sensor pixels to form compensated scan data; processing the compensated scan data to apply offset and gain correction to the compensated scan data to form calibrated scan data; processing the calibrated scan data to adjust the calibrated scan data to compensate for human visual perception to form final scan data; and storing the final scan data in a scanner image memory.

Abstract: A method for performing error diffusion halftoning of an image includes subdividing the image into a plurality of tiles, the plurality of tiles including a first tile and a second tile adjacent to the first tile; performing error diffusion processing of the first tile; and performing the error diffusion processing of the second tile based on an output phase of the first tile.

Abstract: Printer (1) is provided with a mode to edit and print forms without reference to or interruption of a host computer and with immediate printing of one or more of the forms. Page data for the forms is preferably stored in flash memory (21) in a high level printer language. Preferably, at initiation of the forms mode at least the first listed document is immediately prepared by the control data processor (17) of the printer in bit mapped form for printing. Documents can be listed on the control panel by name for ready selection for printing.

Abstract: A method for effecting synchronous pulse generation for use in serial communications is provided. The method includes the steps of generating a difference signal representing a signal level difference between at least two data stream signals; providing a clock signal; providing a counter, defining a sample count value of the counter; incrementing the counter in relation to the clock signal; and determining whether a current count value of the counter corresponds to the sample count value. If the current count value corresponds to the sample count value, then the method performs a step of generating a synchronous pulse.

Abstract: Printer (1) is provided with a mode to edit and print forms without reference to or interruption of a host computer and with immediate printing of one or more of the forms. Page data for the forms is preferably stored in flash memory (21) in a high level printer language. Preferably, at initiation of the forms mode at least the first listed document is immediately prepared by the control data processor (17) of the printer in bit mapped form for printing. Documents can be listed on the control panel by name for ready selection for printing.

Abstract: A method for effecting synchronous pulse generation for use in variable speed serial communications is provided. The method includes the steps of obtaining a communication link speed; generating a difference signal representing a signal level difference between at least two data stream signals; providing a clock signal; providing a counter; defining a sample count value of the counter using the communication link speed; incrementing the counter in relation to the clock signal; and determining whether a current count value of the counter corresponds to the sample count value. If the current count value corresponds to the sample count value, then the method performs a step of generating a synchronous pulse.

Abstract: A method for effecting synchronous pulse generation for use in serial communications is provided. The method includes the steps of generating a difference signal representing a signal level difference between at least two data stream signals; providing a clock signal; providing a counter; defining a sample count value of the counter; incrementing the counter in relation to the clock signal; and determining whether a current count value of the counter corresponds to the sample count value. If the current count value corresponds to the sample count value, then the method performs a step of generating a synchronous pulse.

Abstract: Printer (1) is provided with a mode to edit and print forms without reference to or interruption of a host computer and with immediate printing of one or more of the forms. Page data for the forms is preferably stored in flash memory (21) in a high level printer language. Preferably, at initiation of the forms mode at least the first listed document is immediately prepared by the control data processor (17) of the printer in bit mapped form for printing. Documents can be listed on the control panel by name for ready selection for printing.

Abstract: An improved data acquisition system interface provides virtually constant sampling of input signals and provides those signals in a digitized format to a data acquisition unit that may not be able to sample at a constant rate without missing or “losing” some of the samples. The present invention acts as a front end interface that temporarily latches the sampled data, expands the data into multiple parallel signals, then stores the multiple parallel signals in a dual-port FIFO memory unit. Finally, the multiple parallel signals are transferred into the data acquisition unit at a lower frequency, and the transfer operations take place only when the data acquisition unit is ready to accept data. Since the front end misses no sampling intervals (i.e., it always takes a sample according to an extremely constant frequency crystal clock), then the data acquisition unit will be provided with all of these samples without losing any data.

Abstract: The present invention is directed to systems and methods for formatting hardware for a printhead, for use in a printing device. The systems and methods of the present invention can support the formatting function with hardware formatting logic. This hardware formatting logic can support multiple printhead platforms. The hardware formatting logic of the present invention can perform bit shifting, resolution reduction, bit per pixel reduction, data masking for shingling, and input data sourcing. The present invention can also include a system processor further including an embedded ARM processor which can fetch and execute instructions and/or firmware. These instructions can direct the embedded processor to configure a format block included within the system processor. The format block can be configured by the system processor via one or more control registers.

Abstract: Error diffusion is performed upon input image data. In one aspect, multiple error diffusion processing elements perform error diffusion on a selected pixel in parallel. In another aspect, the error diffusion logic is integrally formed with a fast local memory in the same electronic device, such as an ASIC. The error data produced by the error diffusion logic for a pixel is buffered in the fast local memory until it is to be used by the error diffusion logic on other pixels. In still another aspect, a first-in-first-out (FIFO) buffer regulates or buffers the color image data between the output of a color conversion system, such as a colorant lookup table, and the input an error diffusion processing element. In yet another aspect, the error diffusion logic has tagging logic that produces and stores an indicator, either in the output data stream itself or in a separate area, to indicate whether a raster contains printable data.

Abstract: The present invention is directed to systems and methods for formatting hardware for a printhead, for use in a printing device. The systems and methods of the present invention can support the formatting function with hardware formatting logic. This hardware formatting logic can support multiple printhead platforms. The hardware formatting logic of the present invention can perform bit shifting, resolution reduction, bit per pixel reduction, data masking for shingling, and input data sourcing. The present invention can also include a system processor further including an embedded ARM processor which can fetch and execute instructions and/or firmware. These instructions can direct the embedded processor to configure a format block included within the system processor. The format block can be configured by the system processor via one or more control registers.

Abstract: An apparatus and method for controlling packet generation in a bus that couples a host to a plurality of devices. The apparatus includes a host controller for use with the bus and the host. The host controller has an SOF packet generator capable of delaying the generation of an SOF packet if there is another transaction occurring in the bus until the transaction is complete, thereby to relax the frame timing of SOF packet generation sequences.

Abstract: A mechanism (120) which can be used in a printer (110), for example, for selectively moving sheets from first and second sheet stacks, including a rotating shaft (123), a mechanism for causing the rotating shaft (123) to rotate in first and second directions, and first and second media picks (121, 122). Rotation of the rotating shaft (123) in the first direction causes the first media pick (121) to move a sheet from the first sheet stack (51) and rotation of the rotating shaft (123) in the second direction causes the second media pick (122) to move a sheet from the second sheet stack (52).

Abstract: An improved signal converter is provided to interface between an IEEE 1284 (parallel) bus or device and an IEEE 1394 (serial) bus or device. The converter in its preferred embodiment is designed for use with printers, in which the printer communicates with the converter through either the converter's 1284 port or its 1394 port. In one system, the converter acts as a “1284-to-1394 converter” to interface between a printer (on the 1394 port) and a host computer (on the 1284 port). In a second system, the converter acts as a “peer-to-peer 1394-to-1284 converter” to interface between a printer (on the 1284 port) and some type of 1394 compliant device (on the 1394 port), such as a digital camera. The converter includes a Link layer that is embedded within an ASIC, which preferably includes a microcontroller or a logic state machine, to facilitate asynchronous data transfer.