Abstract: An optical disc has spatial features (notches, bumps, etc.) that intentionally cause read errors if arbitrary data is recorded on the disc in an area where the special features are located. The spatial features are located such that they occur in the center of longer marks or spaces of pre-determined data patterns. This allows pre-determined data patterns to be written and read without a significant number of errors, while arbitrary data patterns will be subject to a significant number of errors, rendering the arbitrary data unreadable. Control Data ECC blocks are partially pre-determined at least in the areas containing decryption keys, while still permitting some arbitrary data to be written in other areas of the Control Data ECC blocks. Therefore, compatibility with existing drives is preserved, without representing a threat of unauthorized copying of stamped discs.

Abstract: Multiple scans of the same object are obtained, where for any given line on the object to be scanned, the angle of the illumination is different for each scan. The different scans are obtained from different rows of photosensors that are separated. Because the angles of illumination are different, the resulting shadows in each scan are different. The multiple scans may be combined into a single composite color image. In a composite image, a dust particle may generate a series of overlapping shadows, where each shadow is a different color. Searching the composite image for the unique pattern of colors may identify artifacts or defects. Alternatively, the data for one scanned image may be compared to the data for another scanned image, and any differences may be due to shadows, which may indicate defects.

Abstract: A method of automatically configuring a computer peripheral device as a primary device or as a secondary device. There are four possible cases: (1) no other device present, (2) legacy primary device present, (3) legacy secondary device present and (4) second unconfigured jumperless device present. In each example embodiment, the host computer determines whether any legacy devices are present by sending commands that are ignored by unconfigured jumperless devices. If a legacy device is present, the host computer sends a command recognized only by an unconfigured jumperless device commanding the particular configuration for the jumperless device. In a first example embodiment, jumperless devices assert a signal after reset with a timing that is dependent on an electronically readable identification on the device. For case (4), the first device to assert the signal becomes the secondary device.

Abstract: A method for automatically cropping, rotating, and scaling a scanned image to ensure that a printed copy of the scanned image is the same size as the original, when possible. The method attempts to honor the default or operator designated orientation of the printed image, but will automatically rotate the image if that will eliminate unnecessary image reduction. Optimal orientation and scaling factors are automatically determined based on the target page size and the size and shape of the information of interest in the original image (not the boundaries of the original document). The operator selects a desired printed orientation (or accepts a default orientation) and selects a desired printed paper size (or accepts a default printed paper size). If an image will fit within the printable margins without rotation or cropping, the image is simply printed without modification. If the image will fit without rotation by cropping white space, then white space is cropped.

Abstract: A picker for data cartridges in a computer information storage library. The picker includes a sleeve for transporting data cartridges, a thumb that can move in one dimension relative to the sleeve, and a single pivoting finger on the thumb. The single finger has an inboard pivot point which results in a self locking action (pulling makes the finger grip tighter). The finger has an armed state for gripping and a splayed state for release. Switching between states is passive, depending only on one dimensional motion of the thumb relative to the sleeve. The finger has a post that travels in tracks in the sleeve. Switching tracks switches finger states. A spring loaded gate in the tracks enables track switching. Potential cartridge wear and binding problems during extraction are eliminated by providing sleeve guides that limit cartridge rotation, by providing a concave guide surface in storage locations, and by proper selection of materials. A corresponding drive has a handle that must be manipulated.

Abstract: An optical waveguide and a shutter are used to guide light from multiple illuminated pixels on a document being scanned onto a single photosensor element. Various methods are disclosed for selecting one pixel at a time for projection onto a single sensor element. Multiple scans are required to capture all the image pixels. The data from multiple scans are then combined to form a single scanned image that has a higher optical sampling rate than the native optical sampling rate of the sensor array. Superresolution image analysis techniques developed for reconstruction of one image from a set of lower resolution images may be applied to provide a diffraction-limited high-resolution image. The waveguide as described also provides an ability to reduce scanning time for lower resolution images. In a first example embodiment, a rotating rod lens with a pattern of black and white areas is used to block/unblock optical waveguide array elements.

Abstract: In an image scanner, rectification of sensor data is computed in real time, so that sensor data do not need to be stored into an image memory. As a result, performance is improved because firmware for sensor data storage and retrieval is eliminated, and fewer devices are arbitrating for access to the image memory. The rectification system is extendable to color scanning by providing one rectification module for each color. In various example embodiments, sensor data are entered into a data buffer configured as a first-in-first-out buffer. The buffer is sufficiently long to hold a little more than one scan-line of data. In a first example embodiment, an interpolator module receives sensor data from fixed locations within the buffer. As new values are entered, old unneeded values are simply discarded. Some special conditions require a distinctive (for example, blank or null) value to be inserted to maintain proper data alignment within the buffer.

Abstract: A lower level cache detects when a line of memory has been evicted from a higher level cache. The cache coherency protocol for the lower level cache places the line into a special state. If a line in the special state is evicted from the lower level cache, the lower level cache knows that the line is not cached at a higher level, and therefore a back-invalidate transaction is not needed. Reducing the number of back-invalidate transactions improves the performance of the system.

Abstract: A method of automatically configuring an autoconfigurable computer peripheral device as a primary device or as a secondary device. There are four possible cases: (1) no other device present, (2) legacy primary device present, (3) legacy secondary device present and (4) second autoconfigurable device present. Host computer device configuration application software provides a signal or numerical data indicating a bit position within an identification number within each autoconfigurable device. If a device identification has a particular logical value at the bit position, the device responds to the signal from the computer. If the device identification has a different particular logical value at the bit position, the device determines whether another device is responding to the signal from the computer. If a first device determines that it should not respond, and a second device responds, the first device provisionally configures itself as a secondary device.

Abstract: A data storage medium includes a data structure, called a disk control block, used for administration and control information for the data storage medium. One medium may contain multiple different disk control blocks, each addressing a different function. Each disk control block includes a control block identifier that specifies the function of the disk control block. Each control block also includes a set of standard access control parameters. If a drive encounters an unrecognized disk control block, the drive can still decode the standard control parameters, so that the drive behavior is not inconsistent with the requirements of the unrecognized disk control block.

Abstract: A method of inhibiting copying of digital data. In a first embodiment, a sequence of symbols is added to original data, the sequence of symbols selected to encode into channel bits having a large accumulated digital sum variance. The sequence of symbols is then encoded by a special encoder that generates special channel bits that don't have a large accumulated digital sum variance. The special channel bits may be unambiguously decoded, but the resulting decoded symbol sequence will likely be reencoded into channel bits having a large accumulated digital sum variance. In a second embodiment, a single symbol in the sequence of symbols is replaced after error correction symbols have been added. The sequence of symbols with one substituted symbol is encoded into channel bits that don't have a large accumulated digital sum variance.

Abstract: A firmware controlled device saves status and configuration information in a separate portion of memory that is not affected by a firmware update. In addition, information that may change during a firmware update, and may need to remain constant, is saved in the separate portion of memory that is not affected by a firmware update. In a first example embodiment, a reset process for the firmware controlled device is divided into two portions. In a first portion of the device reset process, the contents of the separate portion of memory are updated, either from firmware or by interaction with other devices. In a second portion of the device reset process, all other reset functions are performed. The first portion of the reset process is performed only during a power-on reset, or in response to an overall system reset. In particular, the first portion of the device reset process is not performed after a firmware update.

Abstract: A feedback control system has two sinusoidal quadrature position feedback signals generated by photosensitive detectors that sense light reflected from (or transmitted through) position encoding strips that have a reflectance (or transmissivity) that varies sinusoidally along the length of the strip. The system may have one position encoding strip, with two photosensors offset along the length of the strip to provide a ninety degree phase offset. Alternatively, the system may have two strips that are offset in phase by ninety degrees. An error signal is produced directly within the servo loop without requiring computation of ARC-SIN or ARC-COSINE. The error signal is continuous, and position error is not sensitive to photosensor gain.

Abstract: A cache memory system for a computer. Target entries for the cache memory include a class attribute. The cache may use a different replacement algorithm for each possible class attribute value. The cache may be partitioned into sections based on class attributes. Class attributes may indicate a relative likelihood of future use. Alternatively, class attributes may be used for locking. In one embodiment, each cache section is dedicated to one corresponding class. In alternative embodiments, cache classes are ranked in a hierarchy, and target entries having higher ranked attributes may be entered into cache sections corresponding to lower ranked attributes. With each of the embodiments, entries with a low likelihood of future use or low temporal locality are less likely to flush entries from the cache that have a higher likelihood of future use.

Abstract: An apparatus for opening a door in a magnetic data tape cartridge. As a tape cartridge is inserted into a drive, a moveable plunger has a first surface that contacts an extension on the door, opening the door. As the tape cartridge is inserted further into the drive, the cartridge contacts a second surface on the plunger, moving the plunger rearward into the drive. Contacting the second surface for moving the plunger rearward reduces wear and prevents binding.

Abstract: A method of connecting displayed samples of a signal, where the samples are obtained by sequential or random repetitive sampling. Three example embodiments are presented. In a first embodiment, the system decides whether or not to connect to the next consecutive sample, based on the outcome of comparison of the magnitude of the slope to a slew rate threshold. In the second embodiment, the system looks ahead (or behind) up to M samples to see if any samples represent valid slew rates, and connects to the first sample representing a valid slew rate. In the third embodiment, the system looks ahead (or behind) M samples and connects to the sample in the next M samples that represents the smallest valid slew rate. In each embodiment, if no sample represents a valid slew rate, no connection is drawn. In the second and third example embodiments, by looking ahead (or behind) M samples, the system can potentially resolve a waveform with up to M phases and can accommodate trigger placement uncertainty.

Abstract: A transducer position sensing system, in a electromechanical drive, for determining transducer position. A sensor is mounted with a non-adjustable position and without absolute position accuracy, thereby lowering manufacturing costs. The position of the transducer at which the sensor switches states is accurately determined in a manufacturing test fixture and recorded in a permanent memory used by a drive controller. The drive controller can then accurately determine transducer position during subsequent initialization procedures.

Abstract: An apparatus in a computer, called a pending access queue, for providing data for register load instructions after a cache miss. After a cache miss, when data is available for a register load instruction, the data is first directed to the pending access queue and is provided to an execution pipeline directly from the pending access queue, without requiring the data to be entered in the cache. Entries in the pending access queue include destination register identification, enabling injection of the data into the pipeline during intermediate pipeline phases. The pending access queue provides results to the requesting unit in any order needed, supporting out-of-order cache returns, and provides for arbitration when multiple sources have data ready to be processed. Each separate request to a single line is provided a separate entry, and each entry is provided with its appropriate part of the line as soon as the line is available, thereby rapidly providing data for multiple misses to a single line.

Abstract: A process for compensation for real time changes of magnification in an optics system for an image scanner. Targets having high-contrast edges, on both sides of an image to be scanned, are scanned along with the image. If magnification changes, the number of pixels between the targets may change. The pixels between the targets are filtered to generate a fixed number of pixels. Photosensor sensitivity compensation values may be separated into factory compensation values and scanner pre-scan compensation values. Factory compensation values are applied before filtering. Differences between factory compensation values and pre-scan compensation values are applied after filtering.

Abstract: A method of determining whether an electrolytic capacitor is properly connected or reversed in an electronic assembly. In a first embodiment, a non-contacting probe is placed near but not touching the body of the device under test (DUT). One terminal of the DUT is driven by a stimulus (voltage source or current source) while the other terminal is connected to a reference voltage. A voltage is measured at the probe relative to the reference voltage and the device is properly oriented if the measured voltage exceeds a predetermined threshold. In a second embodiment, current through the probe is measured instead of voltage at the probe. In a third embodiment, a non-contacting probe is placed near but not touching both leads of the DUT. Each DUT lead is alternately driven by a stimulus and alternately connected to a reference voltage. For each of the two lead test configurations, a voltage at each DUT lead is measured and current through the non-contacting probe is measured.