Abstract: A computing system controlling is presented which controls input from both a keyboard and a touchscreen. Photo detectors placed in rows and columns along the edge of the touchscreen detect light beams directed across a surface on the touchscreen. The touchscreen indicates to the computing system controller addresses of which detectors do not detect light beams because an object is blocking the light beam path. The computing system controller calculates an average for the row addresses of detectors not detecting light beams, and an average for the column addresses of detectors not detecting light beams. The average is then sent to the host program.

Abstract: An edge generation circuit phase delays pulses of a first signal propagated on an integrated circuit. The edge generation circuit includes a first variable delay circuit located on the integrated circuit, a delay line located off the integrated circuit and a second variable delay circuit located on the integrated circuit. The first variable delay circuit receives the first signal and produces a second signal which is in phase with the first signal. The delay line receives the second signal and produces a third signal. The third signal is delayed in phase from the second by a precise amount. The second variable delay circuit receives the third signal from the delay line and produces a fourth signal. The fourth signal is in phase with the third signal.

Abstract: A scan testable circuit in a computer system is controlled by using a single scan clock and a fixed delay circuit to realize the required scan clocks and a required scan mode enable signal. The multiple signals are generated from a subset of signals supplied to the scan control signal generation circuit. System data and scan data are routed through a multiplexer to test or initialize lines and circuitry. A scan control signal generation circuit according to the invention has the advantage of eliminating as excess a scan mode enable signal originating elsewhere in the computer system, thereby eliminating unneeded signal traces while minimizing the number of pins required for this function. In a first embodiment, a scan mode enable signal is generated from one of two scan clocks. In a second embodiment, both scan clocks and the scan mode enable signal are generated from a single source clock.

Abstract: A computer having a file management system is presented. The file management system includes a plurality of application programs, a plurality of data files, a plurality of class data structures and a plurality of object data structures. Each class data structure includes a reference to an application program within the plurality of application programs. Each object data structure includes a reference to a class data structure from the plurality of class data structure and a reference to at least one data file from the plurality of data files.The use of object data structures adds a layer between a user of the computer and data files. This allows for the computer to refer to an object data structure and associated access files using a tag which is inaccessible to the user. The user refers to an object based on the physical location of the object on the screen. The user may also give the object data structure a name, which is wholly unconnected to the value of the tag.

Abstract: A system uses variable ranges to support symbolic debugging of optimized code. A debug symbol table is constructed which includes descriptions of each user resource in source code. Additionally, a range table is constructed. The range table contains, for each user resource which is stored in numerous locations during execution of the code, a list of ranges and a description of where the user resource may be found during each range. If the user resource is stored as a constant during a particular range, the value of the constant may be stored in the range table. The description of each user resource in the debug symbol table includes a flag which indicates whether there is a list of ranges in the range table for a particular user resource. If there is, the description of the particular user resource will include a pointer to the list of ranges for that user resource.

Abstract: In a computing system a method for performing a multiplication of a first multiplicand and a second multiplicand is presented. The computing system includes a plurality of registers, an instruction decoder, an arithmetic logic unit, and a preshifter. The first multiplicand is divided into a plurality of equal length sections. Each section includes "n" bits, where "n" is an integer greater than one. The second multiplicand is placed in a first register from the plurality of registers. A second register from the plurality of registers is cleared to zero. For each section from the plurality of sections, starting with a first section containing high order bits of the first multiplication and proceeding to a last section of the first multiplicand containing low order bits of the first multiplicand the following three substeps. First, when the low order bit of a current section is a "1", the contents of the first register are added to the contents of the second register via the arithmetic logic unit.

Abstract: An instruction is presented to the cache; the instruction includes a cache control specifier which identifies a type of data being requested. Based on the cache control specifier, one of a plurality of replacement schemes is selected for swapping a data block out of the cache.

Abstract: A hand-controlled mechanism is described for producing signals to move the position of a cursor in a computer display. The mechanism includes a shaft with an elongated axis. A plurality of conductors are wrapped around the shaft and a cylindrical member is mounted for both rotary and lateral movements along the shaft. Signal drivers are provided for applying an energizing signal to a sequence of the conductors. The cylindrical member is provided with conductive plates which overlap a plurality of the conductors, the plates acting to couple an energizing signal applied to one conductor to other conductors which are overlapped by the plates. A decoder senses the coupled energizing signals and provides an output indicative of the position of the cylindrical member to accordingly control a cursor's position. In a preferred embodiment, first and second conductor groups are helically wrapped about the shaft in opposite directions and with orthogonal pitches.

Abstract: A device and method for filling open boxes, containing such products as electronic equipment, with loose fill. The boxes are fed one at a time to a conveyor in random order. A bar code applied to each box, giving the box size, is scanned. The boxes are longitudinally centered by electric eyes actuating a brake at a centering station along the conveyor. The boxes are then widthwise centered by a pair of successively actuated cylinders. A pump-up cylinder at the centering station is actuated to lift a centered box to a predetermined height set by said bar code. A fill valve for loose fill has a supply of loose fill at its upper end fed to it through a feed pipe by gravity, the loose fill flowing by gravity, once the valve is opened, until its feed pipe is plugged, and then it is shut off. The pump-up cylinder then lowers the box to the conveyor. A series of air-blasts, sent to the box further along the conveyor, levels any mountain of loose fill that forms during the feeding of the loose-fill.

Abstract: A method of retrieving data from a multi-set cache memory in a computer system. An address, which includes an index, is presented by the processor to the cache memory. The index is utilized to access the cache to generate an output which includes a block corresponding to the index from each set of the cache. Each block includes an address tag and data. A portion of the address tag for all but one of the blocks is compared with a corresponding portion of the address. If the comparison results in a match, then the data from the block associated with match is provided to the processor. If the comparison does not result in a match, then the data from the remaining block is provided to the processor. A full address tag comparison is done in parallel with the "lookaside tag" comparison to confirm a "hit.

Abstract: A modular compiler is used to compile code for execution by an agent engine and a plurality of application programs. The modular compiler includes a class independent compiler which parses program code which is to be executed by the agent engine. The modular compiler also includes a class dependent parser for each application program. Each class dependent parser parses program code which is to be executed by its respective application program. When an application program is added to the computing system, an associated class dependent parser is added to the modular compiler. When an application program is removed from the computing system, the associated class dependent parser is removed from the modular compiler.

Abstract: A solderless surface mount card edge connector is presented. In one embodiment, a connector is attached to a printed circuit board 53. The connector includes a plurality of contacts and extrusions. A daughter board includes a rigid portion on which are attached a series of fingers. When the rigid portion of the daughter board is placed within the connector, the plurality of contacts are pressed downward and establish electrical contact with electrical regions on the mother board. Also, the downward force is transferred by the contacts into horizontal pressure so that electrical contact is established between the plurality of contacts and the series of fingers. In order to maintain the pressure two metal threaded spacers are pinned to the daughter board and fastened to the mother board via screws. Once tightened the assembly is protected from dislodging, even under vibration. The downward pressure, and thus electrical contact, is maintained.

Abstract: A method and apparatus for fault tolerant communication among a plurality of I/O controllers and a communication controller using an I/O bus having byte-parallel and bit-serial data lines. Each controller is connected to the bit-serial and byte-parallel data lines and the CPU communication controller is capable of selectively indicating which set of lines shall be used for communicating information. When serial communication is desired, a switching signal is transmitted by the CPU communication controller on the serial data line whereupon the I/O controllers switch communication from the byte-parallel data lines to the bit-serial data line. Serial arbitration conflicts are avoided by allocating a time interval to each I/O controller. Each time interval is divided into 3-bit periods. An arbitrating I/O controller asserts the first itself bit true, asserts the second bit false, and disconnects from the bus during the third bit period to separate in time the modules connected to the bus from each other.

Abstract: An apparatus which corrects single bit errors and detects double bit errors including an encoder/decoder. During encoding the encoder/decoder produces a plurality of parity bits. These parity bits allow the correction of single bit errors in transmission. The encoder/decoder includes a plurality of arrays. Each array consists of logic gates arranged in the form of a binary tree. When the encoder/decoder is used in decoding, the encoder/decoder produces a plurality of syndrome bits. These syndrome bits are used to correct single bit errors in transmission. Error correction circuitry composed of logic gates receive the syndrome bits and generate flipper bits used in error correction. When a first data bit for which a first flipper bit is being generated is used in the production of a majority of syndrome bits, a logic gate which generates the first flipper bit receives as input only syndrome bits in the production of which the first data bit was used.

Abstract: Apparatus and method for selecting entries within a plurality of entries. The preferred embodiment of the invention includes a search control processor which causes an edit box and a list box to be displayed on a display. In the list box is displayed a subset of entries from a plurality of entries. As letters are typed on a keyboard, the letters are displayed in the edit box. The search control processor causes a first entry from the plurality of entries to be highlighted when the first letter(s) of the first entry match the letters displayed in the edit box and when the first entry is in alphabetical order before any other entry from the plurality of entries whose first letter(s) match the letter(s) displayed in the edit box. When a user presses "ENTER" or some other designated key on the keyboard the search control processor selects the entry highlighted on the screen.

Abstract: An improved tilt and swivel mechanism is presented in accordance with the preferred embodiment of the present invention. The mechanism includes a base on which is placed a rocker. The rocker moves in a rocking motion with respect to the base. The rocker is prevented from moving in a sliding motion with respect to the base. The present design allows for simplicity of manufacture and maximum ease of use.

Abstract: A strain relieving device for electric cables of different diameters comprises a base plate and three rows of cylindrical pins extending perpendicularly to a plane of the base plate with the pins of the inner row being asymmetrically offset from the pins of the outer rows. Cables of different diameters are fitted between the pins, where they are retained by friction forces. A strain relieving device of this type facilitates considerably the operation of fitting and exchanging cables without the need for any tool.

Abstract: A calculating device is presented which displays a stack containing values most recently calculated and utilized, in accordance with the preferred embodiment of the present invention. The calculating device also displays a label for each value. When a new valve is added to the stack, the stack labels are searched to see if there is a value on the stack having the same label. If so the duplicate value and its label are removed from the stack.

Abstract: An improved scanner is presented which enables a user to preview scan a picture and set out on a screen exactly what portion of the picture he desires to scan. The scanner allows a preview scan of the picture to be made. The preview scan presents a preview image. The user is able to specify what portion of the picture he wants by enclosing that portion of the preview image in a box. Then the scanner performs a final scan which scans only the specified portion of the picture. When performing the final scan, the user may select a percentage amount to reduce or enlarge the image when printed as a printed copy. As the user changes the percentage amount, the dimensions of the resulting printed copy are displayed. The dimensions are calculated by determining the dimensions of the portion to be scanned, and reducing or enlarging the dimensions proportionate to the amount the printed copy is reduced or enlarged.