Abstract: A modem (200) for connecting a computer (100) or the like to a telephone network for data transmission purposes, the modem being of the type including a modulation/demodulation circuit for converting the digital signals of the computer into analog signals capable of being conveyed by the telephone network and vice versa, a computer interface circuit, and a telephone line interface circuit specially designed for a telephone network of a given type. The modem is characterized in that it comprises: a main circuit (210) designed to be placed inside the computer box (102) and incorporating the modulation/demodulation circuit (214) and the computer interface circuit (216); an auxiliary circuit (220) situated in a box (225) external to the computer box and incorporating the telephone line interface circuit; and disconnectable connection means (Cl, 230, 232) between the auxiliary circuit and the main circuit.

Abstract: A three degrees of freedom interactive display controller device is disclosed, comprising a hand manipulable housing unit having an opening for the passage of a mouse ball, two motion detectors for detecting the movement of the mouse ball and converting that motion to output signals controlling the translational movement of an object on the display of a computer and a finger operated conveyor belt or roller for controlling the translational motion of the object with respect to a third translational axis. All translation controls are operable to be physically moved in a direction which corresponds to the desired simulated direction of movement of the object on the display. The physical motion of each control is unbounded and the actual physical position of the housing unit is independent of the simulated position of the object on the display.

Abstract: The subject invention comprises a printer system for a serial printer having an optical sensor detection system for the alignment of images on a sheet of print media, the correction of misalignment as a result of inaccurate alignment of the print media and the determination of the orientation of print media in a printer.

Abstract: A keyboard having the ability to predictively display different characters in association with its various keys within a variety of predefined character set layouts, based upon either the character preceeding an insertion point in a corresponding text field on a display or the last character entered from the keyboard is disclosed. Although each key of the keyboard is capable of displaying numerous different characters, each key represents only one character at a time and each character is displayed at only one key location. The user can also manually change character set layouts. When a user selects a particular key or selects an insertion point within the text field, all keys are updated to display a character set layout that corresponds to the set of characters from which the user would be most likely to want to select a character from next, based upon the frequency of that particular character combination being used in either a particular language or application.

Abstract: An apparatus and method are disclosed for transferring data between devices located on a serial data bus of a data communication system. A first counter and flag are provided which are associated with a device on the serial data bus. The first counter and flag are coupled to the serial data bus for determining temporal periods of high signal levels on the data bus. A second counter and flag also associated with the device on the serial data bus is coupled to the data bus for determining temporal periods of low signal levels on the data bus. A logic demodulator is provided which is coupled to the first and second counter and flag for demodulating the high and low signal levels to binary data and for using this binary data to perform a pertinent function of the device. A transmitter is coupled to an output of the first and second counter and flag and to the demodulation logic for modulating binary data received from the device while performing its pertinent function.

Abstract: An electrical connector that electrically couples a circuit board to another electrical device. The connector has a flexible circuit board with at least one electrical conductor that is attached to a flexible dielectric sheet. Attached to the electrical conductor is an electrically conductive elastomer adapted to engage conductive pads on the surface of the circuit board. The connector has a plate or other member that presses the conductive elastomer onto the conductive surface pads, creating an electrical path between the conductor and the circuit board. The conductor is attached to the electrical device, wherein the electrical device is electrically coupled to the circuit board.

Abstract: A method for performing inter-processor communications in a multiprocessor system combines the sending of a message with the sending of a message interrupt. Messages are exchanged through a shared memory organized into pages, each of which may be "owned" by a processor. When a sending processor executes a store instruction that stores its operand to a memory area owned by a destination processor, a message interrupt is presented to the destination processor. If the destination processor is interrupt enabled, the operand of the store instruction is stored at the address specified by the store instruction and that address is stored in a register of the destination processor. Execution of the store instruction by the sending processor then completes.

Abstract: A circuit for converting RGB to composite video. The circuit is particularly useful in a video overlay application. Notch filters are used both in the video path and keying path. The notch filters are centered at frequenices equal to the dot clock frequency of the RGB divided by integers where the result of this division falls within the chroma subcarrier spectrum.

Abstract: The subject invention is an optical sensor detection system for a serial printer useful for the determination of alignment and misalignment of images on a sheet of print media and the correction of misalignment. The present invention includes a photoelectric sensor mounted on the carriage of a serial type printer to locate various indicator markings.In operation the sensor detects the position of a midpoint indicator when the carriage travels from right to left, and then from left to right. The positional information is then compared with the assumed mid-carriage position of the print head based upon the time of travel, that is, the predicted position of the sensor assuming no flex in the support members of the print head and no stretch of the belt driving the print head.

Abstract: A circuit for allowing a clock of any specified duty cycle to be created from a clock of the same frequency using standard digital delay lines. In particular, an EXOR function is implemented to generate a clock signal having a frequency which is twice the frequency of its input signals by using standard logic components such that the active branch for each input edge has an independent path to the output signal. In this manner, if a time delay is introduced into the active branch and only the active branch, the corresponding output edge and only that edge will be delayed by a like amount. Over a complete cycle of the input waveforms, four output edges are produced (two clock cycles). By varying the delay on the input branches, these output edges can be placed independently and arbitrarily within the period. As such, an output waveform having any desired duty cycle can be created independent of the phase relationship between the two input waveforms.

Abstract: An arrangement which includes apparatus for signifying the source of data to be displayed, apparatus for generating lines of data to fit between the lines of interlaced data to be presented on a non-interlaced output display device, and apparatus for generating lines of data to be presented on an interlaced display from a larger number of lines representing non-interlaced data.