Patents by Inventor Stephen C. Purcell

Stephen C. Purcell has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6816593
    Abstract: A method and apparatus for transposing bits include processing that begins by receiving a multiple bit input. The multiple bit input may be received from memory for executing a read operation from a processing device or for a write operation to memory. The processing continues by determining whether a transposed bit function is enabled. When the transposed bit function is enabled, a set of tri-state transposed drivers are enabled to couple out bit lines to the multiple bit input in a transposed fashion. In addition, a set of tri-state non-transposed drivers are disabled such that they are not coupled to the output bit lines. When the transposed bit function is not enabled, the non-transposed drivers are enabled and the tri-state transposed drivers are disabled such that the multiple bit input, when coupled to the output bit lines, is not transposed.
    Type: Grant
    Filed: December 23, 1999
    Date of Patent: November 9, 2004
    Assignee: ATI International SRL
    Inventors: DeForest Tovey, Stephen C. Purcell
  • Patent number: 6775414
    Abstract: A method that decodes serially received MPEG variable length codes by executing instructions in parallel. The method includes an execution unit which includes multiple pipelined functional units. The functional units execute at least two of the instructions in parallel. The instructions utilize and share general purpose registers. The general purpose registers store information used by at least two of the instructions.
    Type: Grant
    Filed: November 19, 1999
    Date of Patent: August 10, 2004
    Assignee: ATI International SRL
    Inventors: Chad E. Fogg, Nital P. Patwa, Parin B. Dalal, Stephen C. Purcell, Korbin Van Dyke, Steve C. Hale
  • Patent number: 6763452
    Abstract: A method and a multiprocessor computer for execution of the method. A first CPU has a general register file, an instruciton pipeline, and profile circuitry. The profile circuitry is operatively interconnected and under common hardware control with the instruction pipeline. The profile circuitry and instruction pipeline are cooperatively interconnected to detect the occurrence of profileable events occurring in the instruction pipeline. The profile circuitry is operable without software intervention to effect recording of profile information describing the profileable events into the general register file, without first capturing the information into a main memory of the computer. The recording is essentially concurrent with the occurrence of the profileable events.
    Type: Grant
    Filed: June 24, 1999
    Date of Patent: July 13, 2004
    Assignee: ATI International SRL
    Inventors: Paul H. Hohensee, John S. Yates, Jr., Korbin S. Van Dyke, David L. Reese, Stephen C. Purcell
  • Patent number: 6745318
    Abstract: An apparatus that provides configurable processing includes a fetch module, a decoder, and a dynamic arithmetic unit. The fetch module is operable to fetch at least one instruction and provide it to the decoder. The decoder receives the instruction and decodes it. The dynamic arithmetic logic unit receives the decoded instruction and configures at least one configurable arithmetic logic unit to perform an operation contained within the decoded instruction.
    Type: Grant
    Filed: August 18, 1999
    Date of Patent: June 1, 2004
    Inventors: Sanjay Mansingh, Niteen Patkar, Korbin Van Dyke, Stephen Hale, Dee Tovey, Nital Patwa, Stephen C. Purcell
  • Patent number: 6643726
    Abstract: An integrated computing system includes at least one processor formed on a substrate, wherein the processor operates at a processor rate. The integrated computing system further includes a global bus that is coupled to the at least one processor and is formed on the substrate. The global bus supports transactions (e.g., data, operational instructions, and/or control signaling conveyances) at a rate that is equal to or greater than the processing rate. The integrated computing system further includes a device gateway and memory gateway that are operably coupled to the global bus and formed on the substrate. The device gateway provides an interface for at least one device (e.g., internal or external) to the global bus. The memory gateway provides an interface between the global bus and memory.
    Type: Grant
    Filed: August 18, 1999
    Date of Patent: November 4, 2003
    Assignee: ATI International SRL
    Inventors: Niteen Patkar, Ali Alasti, Don Van Dyke, Korbin Van Dyke, Shalesh Thusoo, Stephen C. Purcell, Govind Malalur
  • Patent number: 6460065
    Abstract: A circuit for shifting the number of partial product bits per column in an adder tree is provided. A partial product bit is generated having a weight 22k that has a 1 value only if one input bit of weight 2(k−1) has a 0 value while another input bit of weight 2k has a 1 value. Another more significant partial product bit of weight 2(2k+1) receives the same input bits and has a 1 value only if both of the input bits have a 1 value. In this manner, the number of partial product bits in the column of weight 22k is decreased by 1 while the number of bits is the column of weight 2(2k+1) is increased by 1. Therefore, if the column of weight 22k had the greatest number of partial product bits of all columns, and if the column of weight 2(2k+1) had at least two fewer bits than the column of weight 22k, the total maximum number of bits for all the columns is reduced by 1.
    Type: Grant
    Filed: September 22, 1998
    Date of Patent: October 1, 2002
    Assignee: ATI International SRL
    Inventor: Stephen C. Purcell
  • Patent number: 6449671
    Abstract: A method and apparatus for busing data elements within a computing system includes processing that begins by providing, on a shared bus, a first control signal relating to a first transaction during a first bus cycle. The processing continues by providing a second control signal relating to a second transaction and a first address signal relating to the first transaction during a second bus cycle. The processing continues by providing a third control signal relating to a third transaction and a second address signal relating to a second transaction during a third bus cycle. The processing then continues by providing a first status relating to the first transaction and a third addressing signal relating to the third transaction during a fourth bus cycle. The processing then continues by providing a second status relating to the second transaction during a fifth bus cycle.
    Type: Grant
    Filed: June 9, 1999
    Date of Patent: September 10, 2002
    Assignee: ATI International Srl
    Inventors: Niteen A. Patkar, Stephen C. Purcell, Shalesh Thusoo, Korbin S. Van Dyke
  • Patent number: 6430646
    Abstract: A method and apparatus for interfacing a processor with a bus includes processing that begins by storing transactions initiated by the processor into a buffer. The processing then continues by selecting one of the transactions stored in the buffer and placing the selected transaction on the bus. The processing continues by monitoring progress of fulfillment of each transaction in the buffer and flagging a transaction when it has been successfully completed. The processing also includes processing at least two related transactions prior to selecting one of the transactions from the buffer where, if transactions can be processed locally, they do not need to be transported on the bus. In addition, the processing includes monitoring the bus for related transactions initiated by another processor such that these transactions can be more efficiently processed. The related transaction on the bus would correspond to a transaction queued in the buffer.
    Type: Grant
    Filed: August 18, 1999
    Date of Patent: August 6, 2002
    Assignee: ATI International Srl
    Inventors: Shalesh Thusoo, Niteen Patkar, Korbin Van Dyke, Stephen C. Purcell
  • Patent number: 6415311
    Abstract: A carry save multiplier receives two input values having respective bit lengths A and B and provides sum and carry values, each having bit lengths A+B+1. A carry prediction circuit receives the most significant bit of the sum and carry values and provides an extension bit to be merged with less significant bits of the sum and carry bits. A carry save adder receives the altered sum and carry values, as well as a third input value to provide second sum and carry values. The second sum and carry values are added in a carry propagate adder to form a resulting value. This allows for a faster multiplication to form a product, and the faster addition of this product to another value such as an accumulator value.
    Type: Grant
    Filed: June 24, 1999
    Date of Patent: July 2, 2002
    Assignee: ATI International Srl
    Inventors: Stephen C. Purcell, Nital P. Patwa
  • Patent number: 6393453
    Abstract: A circuit for squaring an n-bit value includes a partial product bit generator which logically AND's a bit of the n-bit value having a weight 2k (k is an integer) with the same bit of weight 2k to generate a partial product bit of weight 22k. Another partial product bit generator receives and logically AND's a bit of the n-bit value of weight 2k and a bit of weight 2m (m is an integers) to generate a partial product bit of weight 2(k+m+1). The second partial product bit generator may be the only partial product bit generator in the squaring circuit to logically AND the bit of weight 2m and the bit of weight 2k. The circuit may also include other partial product bit generators. However, the required number of partial product bit generators is significantly reduced by about ½ compared to the conventional squaring circuit. The associated Wallace tree structure is simplified and made smaller because of the reduction in partial product bits.
    Type: Grant
    Filed: September 22, 1998
    Date of Patent: May 21, 2002
    Assignee: ATI International SRL
    Inventor: Stephen C. Purcell
  • Patent number: 6286023
    Abstract: An adder tree is partitioned into two parts. One multiplexer provides a first bit group to the first part of the tree. A second multiplexer provides a second bit group to the second part of the tree. The two multiplexers provide the same bits groups to the respective parts in response to a first instruction, and provide different bit groups in response to a second instruction. Therefore, the first instruction allows for the single multiplication of the number represented by the first bit group by another number provided to collectively represented to both parts of the tree. The second instruction causes the multiplication of the first bit group by the third bit group in the first part of the adder tree, and causes another multiplication of the second bit group by the fourth bit group in the second part of the adder tree.
    Type: Grant
    Filed: June 19, 1998
    Date of Patent: September 4, 2001
    Assignee: ATI International SRL
    Inventors: Stephen C. Purcell, Nital P. Patwa
  • Patent number: 6127842
    Abstract: In accordance with the present invention, an adder tree structure includes at least two adder stages. In the circuit and method according to the present invention, the first of the two adder stages generates two bits of a common weight and other more significant bits of a weight one bit more significant than the two bits of the common weight. The second of the two adder stages includes an adder that receives the more significant bits generated in the first of the two adder stages. The second adder stage also includes an AND gate which receives and logically AND's the two bits of the common weight to generate a carry-in bit for the adder in the second stage. The above adder tree structure and adding method have an advantage of permitting more input terminals of adders to contain information about the input values to the adder tree structure. Therefore, the adders are used more efficiently and less adders are required to perform a specific function.
    Type: Grant
    Filed: June 24, 1999
    Date of Patent: October 3, 2000
    Assignee: ATI International SRL
    Inventors: Parin B. Dalal, Steve Hale, Stephen C. Purcell, Nital Patwa
  • Patent number: 6122442
    Abstract: A structure and a format for providing a video signal encoder under the MPEG standard are provided. In one embodiment, the video signal interface is provided with a decimator for providing input filtering for the incoming signals. In one embodiment, the central processing unit (CPU) and multiple coprocessors implements DCT and IDCT and other signal processing functions, generating variable length codes, and provides motion estimation and memory management. The instruction set of the central processing unit provides numerous features in support for such features as alpha filtering, eliminating redundancies in video signals derived from motion pictures and scene analysis. In one embodiment, a matcher evaluates 16 absolute differences to evaluate a "patch" of eight motion vectors at a time.
    Type: Grant
    Filed: August 28, 1995
    Date of Patent: September 19, 2000
    Assignee: C-Cube Microsystems, Inc.
    Inventors: Stephen C. Purcell, Didier J. Le Gall
  • Patent number: 6081823
    Abstract: A multiplier has two input value terminals which receive two signed input bit groups. The multiplier also has two output terminals configured to carry a sum and carry bit group representing, in redundant form, a product of the two signed input values. A sign determining circuit generates a sign bit representing a sign of the product of the two input signed values. An extension unit has three input terminals configured to receive the most significant bit of the sum bit group, the most significant bit of the carry bit group, and the sign bit generated by the sign determining circuit. The extension unit is structure to generate a least significant extension bit and a more significant extension bit. The least significant extension bit has one binary state if the sum most significant bit, the sign bit, and the carry most significant bit have the same binary state. The least significant extension bit otherwise has the opposite binary state.
    Type: Grant
    Filed: June 19, 1998
    Date of Patent: June 27, 2000
    Assignee: ATI International SRL
    Inventors: Stephen C. Purcell, Nital P. Patwa
  • Patent number: 6071004
    Abstract: A structure and a format for providing a video signal encoder under the MPEG standard are provided. In one embodiment, the video signal interface is provided with a decimator for providing input filtering for the incoming signals. In one embodiment, the central processing unit (CPU) and multiple coprocessors implements DCT and IDCT and other signal processing functions, generating variable length codes, and provides motion estimation and memory management. The instruction set of the central processing unit provides numerous features in support for such features as alpha filtering, eliminating redundancies in video signals derived from motion pictures and scene analysis. In one embodiment, a matcher evaluates 16 absolute differences to evaluate a "patch" of eight motion vectors at a time.
    Type: Grant
    Filed: August 28, 1995
    Date of Patent: June 6, 2000
    Assignee: C-Cube Microsystems, Inc.
    Inventors: Didier J. Le Gall, Stephen C. Purcell
  • Patent number: 6073156
    Abstract: A multiplier is configured to multiply two signed values to generate sum and carry bit groups representing, in redundant form, a product of the first and second signed values. A sign determining circuit is configured generate a sign bit representing a sign of the product. An extension unit is configured to receive the sum most significant bit, the sign bit, and the carry most significant bit. The extension output terminal configured to carry a replacement bit and an extension bit, the replacement bit having a same weight as the sum most significant bit. The extension unit is structured such that the replacement bit has one binary state only if the sum most significant bit and the carry most significant bit are different. The extension unit is structured such that the extension bit has one binary state only if the sign bit is a binary zero and the sum most significant bit and the carry most significant bit are the same.
    Type: Grant
    Filed: June 19, 1998
    Date of Patent: June 6, 2000
    Assignee: ATI International SRL
    Inventors: Stephen C. Purcell, Nital P. Patwa
  • Patent number: 5910909
    Abstract: A structure and a format for providing a video signal encoder under the MPEG standard are provided. In one embodiment, the video signal interface is provided with a decimator for providing input filtering for the incoming signals. In one embodiment, the central processing unit (CPU) and multiple coprocessors implements DCT and IDCT and other signal processing functions, generating variable length codes, and provides motion estimation and memory management. The instruction set of the central processing unit provides numerous features in support for such features as alpha filtering, eliminating redundancies in video signals derived from motion pictures and scene analysis. In one embodiment, a matcher evaluates 16 absolute differences to evaluate a "patch" of eight motion vectors at a time.
    Type: Grant
    Filed: June 23, 1997
    Date of Patent: June 8, 1999
    Assignee: C-Cube Microsystems, Inc.
    Inventors: Stephen C. Purcell, Didier J. Le Gall
  • Patent number: 5870497
    Abstract: A decoder for compressed video signals comprises a central processing unit (CPU), a dynamic random access memory (DRAM) controller, a variable length code (VLC) decoder, a pixel filter and a video output unit. The microcoded CPU performs dequantization and inverse cosine transform using a pipelined data path, which includes both general purpose and special purpose hardware. In one embodiment, the VLC decoder is implemented as a table-driven state machine where the table contains both control information and decoded values.
    Type: Grant
    Filed: May 28, 1992
    Date of Patent: February 9, 1999
    Assignee: C-Cube Microsystems
    Inventors: David E. Galbi, Stephen C. Purcell, Eric Chi-Wang Chai
  • Patent number: 5864704
    Abstract: A media engine is disclosed herein which incorporates into a single chip structure the seven multimedia functions of video, 2D graphics, 3D graphics, audio, FAX/modem, telephony, and video-conferencing. In accordance with the present invention, a media engine includes a signal processor which shares a memory with the CPU of the host computer and also includes a plurality of control modules each dedicated to one of the seven multi-media functions. The signal processor retrieves from this shared memory instructions placed therein by the host CPU and in response thereto causes the execution of such instructions via one of the on-chip control modules. The signal processor utilizes an instruction register having a movable partition which allows larger than typical instructions to be paired with smaller than typical instructions.
    Type: Grant
    Filed: October 10, 1995
    Date of Patent: January 26, 1999
    Assignee: Chromatic Research, Inc.
    Inventors: James Thomas Battle, Andy C. Hung, Stephen C. Purcell
  • Patent number: 5815646
    Abstract: A method and structure including four video decompression structures and eight memory banks are provided for decoding high definition television (HDTV) signal. In this HDTV decompression structure, the 1920.times.1080 pixel display space is divided into four vertical sections of 480.times.1080 pixels. Each memory bank stores the values of pixels in one non-overlapping group of 240.times.1080 pixels. Each decompression structure decodes a 480.times.1088-pixel picture area with access to up to two additional 240.times.1088-pixel picture areas. The video decompression structures decode the vertical sections in lock-step to avoid the problem of the same bank of memory being accessed by more than one video decompression structure. In one embodiment of the present invention, a macroblock fetch can cross 1-4 DRAM page boundaries. So, in order to maintain the lock-step relationship of the video decompression structures, each page mode access is limited to fetching only an 8.times.
    Type: Grant
    Filed: October 11, 1994
    Date of Patent: September 29, 1998
    Assignee: C-Cube Microsystems
    Inventors: Stephen C. Purcell, David E. Galbi, Frank H. Liao, Yvonne C. Tse