Abstract: A stacking and orientation independent multiple contact plug and socket electrical connector has a central connector body with a "plug" extending outward on one face, and a "socket" recessed inward on an opposite face. The plug and socket are aligned along a common axis, but are on opposite faces of the central connector body. The plug is an electrically insulated post extending outward from the central connector body and having multiple electrically conductive circular contact rings encircling the post. The socket is a cylindrical recess into the central connector body designed to accept the plug of another similar connector. The socket has multiple electrical wiper contacts spaced along an electrically insulating inner wall of the recess for contacting to the circular contact rings of a post.
Abstract: The present invention comprises an apparatus and method for automatically feeding manually inserted print media into a printer or similar device and substantially aligning the same, thereby eliminating the need to correct the alignment of the print media manually. The invention automatically feeds the media to the printer by means of a first paper drive having a low torque which aligns the media in the nip and then actuates the paper feed drive. The method of aligning the media is also disclosed.
Abstract: A cache management system for a computer system having a central processing unit, a main memory, and cache memory including a memory management unit for transferring page size blocks of information, apparatus for reading information from main memory, apparatus for writing information to the cache memory, and apparatus for overlapping the write of information to the cache memory to occur during the read of information from the main memory.
Abstract: A color graphics system for use with a computer. The color graphics system utilizes a look-up table having index values to be stored in a frame buffer. The look-up table is addressed by providing color information, such as RGB color information to the table. The index values may be used to index a second look-up table for providing color information, such as RGB color information. The present invention further disclosed methods of insuring index values provided by the look-up table closely approximate the desired color within the available color space. Further the present invention provided methods for performing arithmetic transfer operations on colors represented by indexes in the frame buffer.
Type:
Grant
Filed:
May 17, 1988
Date of Patent:
November 26, 1991
Assignee:
Apple Computer, Inc.
Inventors:
James Batson, Ernie Beernink, David Fung, Michael Potel, Art Cabral, Cary Clark
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 frequencies equal to the dot clock frequency of the RGB divided by integers where the result of this division falls within the chroma subcarrier spectrum.
Type:
Grant
Filed:
February 1, 1991
Date of Patent:
November 12, 1991
Assignee:
Apple Computer, Inc.
Inventors:
Paul E. Greaves, Michael R. Moore, Stephen G. Perlman, Laurence A. Thompson
Abstract: A circuit which receives RGB and composite video and provides both RGB and composite merged outputs. Merging of RGB signals occur where the input composite signal is converted to RGB; and also, merging occurs of composite signals where the input RGB is converted to a composite signal. 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 frequencies equal to the dot clock frequency of the RGB divided by integers where the result of this division falls within the chroma subcarrier spectrum.
Type:
Grant
Filed:
February 1, 1991
Date of Patent:
November 12, 1991
Assignee:
Apple Computer, Inc.
Inventors:
Paul E. Greaves, Michael R. Moore, Stephen G. Perlman, Laurence A. Thompson
Abstract: A printed circuit board card adapted to fit into a slot and make electrical connections with cooperating terminals in the slot, the slot being disposed on the main circuit board of a personal computer system, the main circuit board including a CPU, memory, a 32-bit address bus with control signals associated therewith, and input/output circuity. The slot is coupled to the 32-bit address bus, being substantially a NUBUS bus, and the slot includes distinct identification line means which provide the slot with an identification number (distinct number) in the computer system. The card includes a decoder means which is coupled to the slot to receive the identification number; the decoder means has memory reservation means which causes 256 megabytes of memory space to be reserved for the card in the slot, such that, where the slot number is X, the 256 megabytes of reserved memory space begins at location $X000 0000 and ends at location $XFFF FFFF.
Abstract: A full-spectrum stereoscopic display system with a tiled display image of alternating tiles from first and second full-spectrum images of a stereo pair of images is covered by an identically tiled polarized mask, with alternating tiles of said polarized mask being cross polarized. When viewed through cross polarized viewing glasses, separate views will appear for the left and right eyes of the viewer.
Abstract: A self-correcting synchronization signal for a communication interconnect which connects multiple units, the synchronization method including the steps of: waiting for a predetermined period of time until the next synchronization signal is due (nominal cycle period); waiting a further period of time for the absence of communications on the interconnect among any of the units, and forming a count of the passage of time during this delay (start delay); forming a synchronization signal including the count of the delay time; and sending the synchronization signal on the interconnect. Also according to this invention, a unit receiving the synchronization signal on the interconnect can update its count of time by the predetermined period of time plus the count of the delay period of time.
Abstract: A method and apparatus for verifying a file stored separately from a computer to be identical with a previous version of the file, before using the file. This verification is done by following a defined procedure to generate a first identifier based on the contents of the previous version of the file, storing this identifier locally on the computer, and storing the file at a separate storage location. Then, at a later time, an unverified second file is retrieved from the separate storage location, the same defined procedure is followed to generate a second identifier, and the first and second identifiers compared to identify a match that verifies the integrity of the second file.
Abstract: An integrated circuit cell module for performing precise time measurements for use in applications such as disk drive controllers. The combination of the cell module and a hard disk controller chip creates a complete hard disk controller in a single chip without the need for external analog components normally required for classic phase lock loop hard disk controllers. A problem in designing such a unified chip is that it must be digital in nature. Therefore, the maximum resolution with which signals generated by the disk drive (Rddata signals) can be measured and signals generated by the controller for writing to disk (Wrdata signals) can be generated is dependent on the clock which drives the controller chip. In hard disk controllers, the data rate is such that the minimum distance between adjacent Rddata or Wrdata pulses is approximately 100 ns which would require an oscillator having a speed which would be impractical in a design.
Abstract: A data compression method which recognizes the adverse conditions of duochrominance-isoluminance and nonlinear color distribution. A mxn block of pixel data is examined to compute two colors and a bitmap which best represent the block generally using a luminance partitioning technique. The original data and the compressed data are examined to determine if the resultant decompresssed image will contain artifact associated with duochrominance-isoluminance or nonlinear color distribution. If these artifacts will occur in the decompressed data, the decompressed data is not used but rather the block is represented by storing the color of each pixel. This method produces compressed images of excellent quality.
Abstract: An adaptive compression/decompression method for color video data with an anti-aliasing mode. 4.times.4 blocks of pixel data are examined to determine which one of four compression techniques should be used on each block. User settable thresholds can be used to shift the types of compression used. Highest compression is obtained when more data is stored in run length blocks of single colors and lowest compression when more data is stored as two colors with a 32-bit bitmap for each 4.times.4 block. One type of compression used provides anti-aliasing.
Type:
Grant
Filed:
March 16, 1990
Date of Patent:
September 3, 1991
Assignee:
Apple Computer, Inc.
Inventors:
Eric M. Hoffert, Gavin S. P. Miller, Lee S. Mighdoll, Stephanie L. Winner
Abstract: A clock circuit for generating two clock signals, one (CLK) having stretched clock phases on a cycle by cycle basis, and the second (2X CLK) being a clock signal having a frequency twice the frequency of the first clock signal which is phase and edge coherent with the first clock signal, including the stretched clock phases. The circuit inputs a signal generated by an oscillator which is twice the frequency of the CLK signal which is then used to generate the CLK signal for use by a microprocessor, either phase of which can be stretched on demand, while the second 2X CLK signal remains phase coherent with the microprocessor CLK signal.
Abstract: A video display apparatus for composing video signals for a raster scanned display on a line-by-line basis. Objects are stored in a video RAM and are packed in the RAM without regard to their location on the display. A separate dispatch table contains information on each object and commands. A dispatcher operates on this information, allowing lines of data and commands to be extracted from the RAM as each video line is composed in a buffer.
Abstract: A printer using meltable solid ink pellets loaded into a reservoir in which a holder with an attached solid ink pellet is inserted through a doorway for access to the reservoir and a release mechanism within the reservoir releases the ink pellet from the holder by engagement of the ink and release mechanism. The holder surrounds the pellet on all but one end and includes keyed projections on the holder for matching to keyed slots on said doorway, such that only a matching keyed holder will pass through said doorway. The keyed projections on the holder are used to open the doorway. The release mechanism includes a bore for receiving and restraining the pellet against rotation of the holder, or can include a thin chisel for severing the connection of the pellet to the holder.
Abstract: A substantially spherical ball to be used in a cursor controlling mouse. The mouse ball is formed from a composition of silicone having zirconium dust dispersed uniformly throughout. The zirconium provides the added weight necessary to keep the ball rolling on a working surface, but is not sufficiently conductive to short electrical components in mouse. The uniform composition provides for the mouse ball to have its gravitional center coincident with its geometric center to inhibit cursor jitter when the mouse is manually moved.