Abstract: A bus circuit for implementing a high speed dominant logic bus for a differential signal. The bus circuit is useful in a communication network having a plurality of multi-port nodes that are coupled by point-to-point links that communicate differential signals. Each port in the node includes a bus driver that receives the differential signal received at the port. The bus driver supplies a differential current signal to a first bus. A terminator circuit is coupled to the first differential bus, to receive the differential current signals supplied from the ports. The terminator circuit, responsive to the differential current signal, outputs a differential voltage signal indicative of either a dominant state or a non-dominant state to a second differential bus, which is coupled to the plurality of ports for transmission. A biasing circuit for the bus drivers allows operation at low voltages, and furthermore insures the zero crossing of the differential voltage signal on the second differential bus.

Abstract: To expedite the run-time construction of resource table, cache files which contain relevant information needed to build a resource table are stored on associated storage media. When a program builds a resource table, all the information that is recorded in the table from a particular storage medium is also stored in a cache file that is kept on that medium. Included in the cache file is information pertaining to the most recent modification date for each folder or directory that contains a resource of interest. The next time that the table is built, the program compares the modification dates stored in the cache file with the actual modification dates of the folders or directories. If the folders and directories have not been updated since the last time the cache file was created, the information contained therein is loaded into the table.

Abstract: A system and method for halftoning multi-level pixels preferably uses a threshold array divided into two or more classes. The classes are ordered in a visitation order. Each class contains at least one element. A halftone cell comprised of a plurality of pixels corresponds to the threshold array. As the intensity level for the halftone cell increases, the pixels corresponding to the elements in the first class are halftoned by fractional values of pixels until all of the pixels in that class reach saturation. As the intensity of the halftone cell increases, none of the pixels corresponding to the elements in any other class change state. Once the pixels corresponding to the elements in the first class are saturated, the pixels corresponding to the elements in the second class are halftoned by fractional values of pixels. In more general terms, the next class in the class visitation order is not addressed until the pixels corresponding to all of the elements in the previous class are saturated.

Abstract: A graphics rendering system includes a continuum, or collection, of quality control data groups, each of which contains a plurality of quality control type variables. Each of the type variables contains a value which selects among a plurality of options in a respective trade-off between rendering quality and rendering speed. Each of the quality control data groups may be associated with the respective quality index. Thus, an application program can select a point on the overall rendering speed/quality rendering trade-off, merely by selecting a quality control index value. Moreover, the application program can make the current quality control index accessible to a user, for example in such an intuitive form as an iconic "quality knob". The mechanism permits the user to have fine control over the rendering speed/quality rendering trade-off, without being concerned with adjustments to the individual rendering parameters.

Abstract: A string inserter for a computer system having a graphical user interface and a pointer capable of interacting with a graphical user interface includes an insertion marker, an insertion initiater, and an insertion implementer. The insertion marker is displayed on a screen of the computer system at an insertion point in displayed text corresponding to a string of text information. The insertion initiater is operative to detect a selection of the insertion marker with a the pointer mechanism of the computer system and to provide an insertion menu on the screen that includes a number of insertion labels. The insertion implementer is responsive to a selection of an insertion label with the pointer and is operative to insert an insertion string corresponding to the selection into the string of text information.

Abstract: A personal computer includes a chassis in which expansion cards and a processor card can be mounted in an upright parallel manner. An end of each expansion card is received in a vertical slot carried by a speaker component of the computer. A baffle member is swingably mounted on the chassis for rotation about a horizontal axis between open and closed positions. In the open position of the baffle member, the expansion cards can be inserted or removed. In the closed position of the baffle member, ribs thereof engage and stabilize upper edges of the cards. Hard and floppy drives are insertable into respective bays disposed within the chassis in a rear-to-front direction (in contrast to a front-to-rear direction), so that EMI shields located in front of those bays do not have to be removed to permit insertion or removal of the disc drives.

Abstract: An audio codec capable of handling complex control and routing of numerous sound inputs is described. The complex control and routing is obtained by weighting various sound inputs in accordance with weighting values and then digitally mixing the weighted sound inputs together. The invention facilitates construction of the audio codec with mainly fixed gain amplifiers, instead of variable gain preamplifiers, thereby saving a large amount of die space and reducing time needed for testing.

Abstract: An apparatus for programmably adjusting output voltage of a constant-voltage battery charger is disclosed. The present invention includes a power circuit for generating an output voltage for charging batteries. This power circuit generates this output voltage as a function of an incoming power source and an incoming error signal. The invention further includes a controller for providing a pulse width modulated (PWM) signal operating at a pre-determined frequency. This PWM signal controls the effective divider ratio of a voltage divider network which is implemented, among other things, for generating the error signal to be fed to the power circuit. The present invention varies the effective divider ratio by programmably applying the pulse width modulated signal from the controller. As a result, the output voltage from the power circuit can be varied to optimally charge batteries of differing types and technologies.

Abstract: An appliance such as a personal computer includes a metal chassis which has a first section, and a second section mounted on the first section. The first chassis section forms a first space in which a motherboard is mounted. The second chassis section forms a second space in which a disk drive is mounted. The second chassis section defines a shield resisting the passage of electromagnetic waves between the first and second spaces to isolate the motherboard from a disk opening for the disk drive thereof.

Abstract: A real time clock includes an oscillator, a digital counter, a temperature sensor, and a digital processor. The digital processor can read the temperature measured by the temperature sensor and utilize this information to generate an adjustment value for the digital counter. The digital counter is coupled to the digital processor and has an adjustment stage which the digital processor writes into in order to compensate for any oscillator error due to temperature variation. The digital processor may also be coupled to memory storing a temperature adjustment look-up table for use in generating the adjustment value. A method of the present invention includes the initial steps of generating an adjustment look-up table and storing it in non-volatile memory.

Abstract: In a system for describing directional sounds in virtual environments, a user creates a sound projection map that constitutes a two-dimensional array of sound intensities for each sound source associated with the virtual environment. At run-time, when a user selects a particular view for a scene in the environment, a hearing area corresponding to that view is calculated. The average intensity for each sound represented within the hearing area is determined from the array, to establish a level at which the sound is to be played. The sound associated with the sound source is then reproduced from a sound track at the determined level, to produce an output sound that creates a sense of place within the environment.

Abstract: A method of compressing data representing a plurality of pixels consecutively arranged along a line of an image to be displayed on a computer controlled display is described. The method includes the step of determining color of an initial pixel of the plurality of pixels. The value of a pixel count is then incremented. The value of the pixel count indicates the number of pixels in that color. The color of an adjacent pixel of the initial pixel is then determined. If the color of the adjacent pixel is identical to the color of the initial pixel, then the adjacent pixel is caused to be the initial pixel and the step of incrementing the value of the pixel count is performed. The method then moves to determine the color of the next pixel. If the color of the adjacent pixel is different from the color of the initial pixel, then a datum indicating the color of the initial pixel and the value of the pixel count is generated.

Abstract: A sleep mode controller, useful for an electronic device such as a computer, can supply multiple clocks with appropriate synchronization and which is capable of dynamic speed switching. The device provides clock signals at various speeds and relationships which can in turn be used to support various functions of the electronic device. The sleep mode controller can be activated and smoothly transition various clock signals from one time domain to a second time domain, each of which has predetermined speeds and clock-signal relationships. Dynamic speed switching is used to reset timing (bus and processor clock) sensitive elements such that computer machine speed (bus and processor clock frequencies) can be changed dynamically without interruption of I/O services or general OS and application level functions.

Abstract: The present invention is directed to systems and methods for encoding (for example, compressing) image data while at the same time, improving both the compression ratio and the perceptibility of the decoded (for example, decompressed) image using a dynamic band recompression scheme. In accordance with exemplary embodiments, portions of a compressed image are decompressed upon occurrence of a predetermined condition prior to compression of an entire frame of image data, and then recompressed with subsequent portions of the original image. Exemplary embodiments achieve enhanced fidelity in a decompressed image even when the image data is compressed without segregation into its scanned and non-scanned components.

Abstract: A method for improving the execution speed of compare operations in graphic software functions running on a RISC processor. A branch instruction in a software function comparing the value of two variables is replaced with an inline compare instruction that encodes the result of the compare into a third variable using an arithmetic shift-left instruction. An inline choice instruction selects the value of one of the two variables using the value of the third variable as a mask. The inline compare and an inline choice instructions reduce processor stalls during execution.

Abstract: A statistical classifier that can be used for pattern recognition is trained to recognize negative, or improper patterns as well as proper patterns that are positively associated with desired output classes. A set of training samples includes both the negative and positive patterns, and target output values for the negative patterns are set so that no recognized class is indicated. The negative patterns are selected for training with less frequency than the positive patterns, and their effect on training is also modified, so that training is focused more heavily on positive patterns.

Abstract: An orientation sensor generates a left orientation signal and a right orientation signal to indicate whether a camera is in an upright orientation, a left orientation, a right orientation, or an inverted orientation. A setting unit retrieves the left and right orientation signals and light intensity signals corresponding to image measurement zones. Based upon the values of the left and right orientation signals, the setting unit uses different weighted combinations of the light intensity signals to determine optimum exposure and focus settings. The orientation sensor includes a first tube and a second tube that each contain an indicating object. The indicating object within each tube selectively provides two orientation signals based upon the camera's orientation relative to an image, thereby changing an orientation signal from a binary "0" signal to a binary "1" signal.

Abstract: A computer system includes a plurality of nodes, each having an associated unique identification and bus address, interconnected by point-to-point links. Device data records are maintained in a memory of the computer system wherein node unique identifications, which are bus reset invariant, are associated with corresponding node bus addresses, which are subject to change with bus resets. A driver associated with a source node initiates a bus transaction and specifies a reference identification for the destination node. The reference identification of the destination node is used to access the device data records to obtain the corresponding destination node bus address. When a bus transaction cannot be completed because a bus reset occurs, the device data records are updated to associate the new bus addresses of the nodes with the corresponding node unique identifications. The new destination node bus address is used to complete the bus transaction that was interrupted by the bus reset.

Abstract: A method and an apparatus for contacting a touch-sensitive cursor-controlling input device to generate button values simulating the button state of a mechanical button switch. This method and apparatus enable an operator to utilize the touch-sensitive cursor-controlling input device to change the value of a ButtonState variable (which simulates the ButtonState of a mechanical button switch) by (1) detecting contact intervals when the user contacts the touch-sensitive input device, (2) detecting gap intervals between subsequent contact intervals, and (3) moving the cursor on the display screen and changing the value of the ButtonState variable based on the duration of the contact and gap intervals. In turn, this button generation capability enables an operator to perform with a single touch-sensitive input device numerous control operations, such as cursor manipulation, click, multi-click, drag, click-and-drag, and multi-click-and-drag operations.

Abstract: A user interface is disclosed that facilitates easy find and display operations that search through the memory of a pointer based computing system. The user interface includes searching methods that are particularly well suited for use in a computer system in which the contents of the memory are divided into a plurality of searchable application files that are each capable of containing a plurality of records. In one aspect of the invention an improved find dialog box is disclosed. In another aspect, a method of selecting local verses global searches together with a method of conducting the chosen search and processing user inputs in response to the search results is disclosed. Additionally, an improved interface for displaying the results of various searches is described.