Abstract: Cover assemblies, capable of being locked and unlocked by means of a key, are configured to be placed over the connectors at each end of an external computer system cable. When these cover assemblies are locked in place, the cable cannot be unplugged from the connector ports of the system devices. When these cover assemblies are unlocked, they can be removed from the cable, and the cable can then be unplugged from the connector ports.A first type of cover assembly is designed to operate with a connector which is fastened in place in its plugged position by means of a pair of screws, while a second type of cover assembly is designed to operate with a connector which is fastened in place by means of a pair of rotatable wire bails. These cover assemblies may also be used to prevent access to connector ports to which cables are not attached by locking in place terminators commonly used on such ports, or by locking in place shells configured for this purpose, if such terminators are otherwise not required.

Abstract: Lockable covers are used to cover either of two types of shield blocks to prevent access to circuits within either of two types of external ports on computing devices. Each such shield block covers the port contacts associated with these circuits, includes locking surfaces for holding the lockable cover in place, and is itself held in place by the attachment features provided on the external port for holding an external cable in place. One such shield block is held in place by a pair of screws extending into threaded holes in the external port, while the other such shield block is held in place by a pair of flexible wire bails rotatably mounted in the external port.

Abstract: Electrical grounding is provided for an optional device in a computer system, and a gap of varying width adjacent to the device is filled with a conductive shield, by means of a flexible grounding spring having a folded central section from which tabs extend in one direction to contact a conductive surface of the device and in the opposite direction to contact a conductive surface of the machine framework. This grounding spring is held by means of a mounting bracket having a slot through which the folded central section extends to be held in place by locking tabs formed in this section.

Abstract: A pivotable power supply for a computer rotates away from the computer circuit board so that servicing of system components located behind the power supply is facilitated. The power supply is provided with a ground strap which remains attached during power supply pivoting thus assuring that the power supply will be grounded after system servicing. Also, a threaded, spring-loaded fastener for locking the power supply in position is designed such that the covers cannot be replaced on the housing unless the power supply is connected to the system circuit board.

Abstract: A method and apparatus for performing data error detection and correction is disclosed for multi-level logic and in particular, three-level trinary logic of levels 0, 1, 2. A source of trinary data supplies individual pieces of data (trits of 0, or 1, or 2) in multiple trit groups (trytes) to two separate check trit generators which generate unique check trits for each tryte input. The check trits from the two check trit generators are compared to form syndrome trits which are used to control an error detection function. For single errors per tryte a data correction function is activated to increment or decrement the incorrect data through a multiplexer. Multiple errors or no error conditions are indicated, but do not gate the data correction function.

Abstract: A print wheel for serial printing devices of the type wherein print fonts are arranged upon a disc print wheel member. The print wheel has both coarse alignment and fine alignment means formed therein; the coarse alignment means for driving the print wheel, and the fine alignment means for accurately positioning the wheel during hammer impact.

Abstract: A computer based technician terminal is connected to a vehicle being serviced using an assembly line data link (ALDL) connection from an on-board computer. The data link provides status information and fault codes. The technician is led through various procedures. During set up, the technician connects an ALDL cable from the terminal to the vehicle, the vehicle indentification number (VIN) is entered and vehicle options are identified. A fault detection procedure (FDP) in the terminal detects vehicle malfunctions by interrogating data received (via the ALDL) from the on-board computer. A fault analysis procedure (FAP), using the fault codes from a table as arguments, does a sequential compare against the contents of a fault analysis table containing fault codes. In a fault sequencing procedure (FSP), for each fault code passed by the FAP, there is a list containing the name(s) of one or more isolation procedures.

Abstract: An advanced display system controller is described for use in automotive vehicles. The controller has electronic circuitry to allow it to be programmed to display monochrome or color graphics and text on an all-points-addressable display device such as a CRT or an Electro-Luminescent (EL) Flat panel. The display resolution and scan rates may be programmed differently depending on the display type and size. The vehicle operator controls the display system via a reconfigurable switch system (RSS), such as an Infrared Touch Panel or Mylar Touch Switch Matrix mounted over the face of the display. In addition, external discrete switches may also be attached to the controller. The controller includes a master microprocessor and a slave microprocessor with preferred partitioning of functions and communicates with other parts of the vehicle via two serial data communication links, a Random Access bus and a Poll/Response bus.

Abstract: In a computerized automotive vehicle diagnostic system, a test probe cable is attached to individual components and consists of a multiple conductor cable which is attached ultimately to the component and to a computer in a technician terminal. Where the probe cable enters the technician terminal the conductors contained within it are fed into a programmable crosspoint switch which is controlled by a microcontroller. Test functions are provided by three programmable resources: (1) A program controlled multimeter, (2) A program controlled DC voltage source and ground sink; and (3) the microcontroller itself which receives and interprets commands from the computer and controls the various probe elements based upon the test commands received.

Abstract: A thermal transfer printing system in which a print scanning head is provided with a series of thermal heating elements. The elements are aligned in a column perpendicular to the line of printing. A sensor is provided to determine where the scanning head is aligned perpendicularly relative to the line of printing. More heating elements are provided on the head than are required for printing. Only those heating elements properly aligned with the line of printing are activated.

Abstract: A ribbon take-up drive mechanism for a universal ribbon cartridge. The cartridge is adapted to engage the ribbon drive shafts of printers of two different designs. The drive shaft positions are different, and the direction of drive shaft rotation is opposite for the two designs. The take-up mechanism is designed such that the ribbon is pinched between the teeth of a direct drive gear and a biased idler gear. The printer of one design drives the ribbon through the direct drive gear. The printer of the second design drives the ribbon through an alternate drive gear, an idler gear and the biased idler gear. In either case, the ribbon is advanced in the same direction.

Abstract: An envelope feeder for mounting on a computer printer, electronic typewriter, word processor or other programmable printer. The envelope feeder uses a centrally located drive separator roller and separating tongue to effect envelope separation.

Abstract: A single piezoelectric transducer is used to drive an array of drop-on-demand ink jet ejectors. This is accomplished by utilizing a plurality of electrodes which divide the piezoelectric transducer into discrete, deformable sections, each section corresponding to an ejector.

Abstract: A print wheel cartridge for a serial printer. The cartridge includes a spring designed to lock the print wheel in the cartridge. The spring automatically releases the print wheel when the cartridge is inserted into the printer.

Abstract: A digital display system includes a monitor arranged to receive digital display data and synchronizing signals to develop displays on a cathode ray tube. The monitor is switched between different line structure and/or color definition modes in response to the polarity of one of the vertical or horizontal synchronizing signals trains. A circuit receives this train to provide control signals to the horizontal time base and/or a color signal code converter. The time base control signal, in accordance with its binary value, controls the frequency of the time base. The color converter, in response to the control signals, either passes color signals received in parallel over six input lines without change to the cathode ray tube drive circuits or converts color signals on four of the input lines to output signals on the six lines to the drive circuits.