Patents by Inventor Qizhang Chao

Qizhang Chao 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: 11487561
    Abstract: According to an embodiment, a system and method are provided for constructing an accurate view of memory and events on a simulation platform. The system memory view can be used with a debug and analysis tool to provide post-processing debug, including searching forward and backward in capture time of the stored memory view to analyze the events of the simulation. The memory is constructed by capturing and storing each memory execution transaction, bus transaction, and register transaction during simulation. Changes in simulation platform hardware state may also be captured and stored in a hardware state database, including switches between process threads detected during the simulation that may update a simulator register. The captured events provide observability into the OS processes, the hardware, and the embedded software of the simulation platform.
    Type: Grant
    Filed: December 24, 2014
    Date of Patent: November 1, 2022
    Assignee: CADENCE DESIGN SYSTEMS, INC.
    Inventors: Andrew Wilmot, Neeti Khullar Bhatnagar, Qizhang Chao, George Franklin Frazier
  • Patent number: 10802852
    Abstract: According to an embodiment, a system and method are provided for supporting interactive debugging of embedded software (ESW) on a simulation platform. A processor model within the simulated system will support a register and memory tracing sub-module. Simulator and emulator breakpoints will be used with the modeled objects within the tracing sub-module. For example, a simulator breakpoint may be set for the task or function that buffers the trace information so it can be written to a file. A database of register and memory values which represent the complete history of register and memory value changes during a simulation can be created from trace information and can be accessed to non-intrusively obtain any processor register or memory value during simulation. The processor register and memory values of the database can also be accessed to symbolically show the behavior of ESW concurrently with hardware behavior in the simulation.
    Type: Grant
    Filed: July 7, 2015
    Date of Patent: October 13, 2020
    Assignee: CADENCE DESIGN SYSTEMS, INC.
    Inventors: Andrew R. Wilmot, Neeti Khullar Bhatnagar, Qizhang Chao, George Franklin Frazier, Yevgen Ryazanov
  • Patent number: 10176276
    Abstract: An apparatus and method for determining an optimal global quantum value for use in event-driven simulations of a device are disclosed herein. The device is simulated using information representative of a device design corresponding to the device, the simulation of the device comprising an event-driven simulation using a provisional global quantum value. Events included in a sequence chart corresponding to the simulation using the provisional global quantum value are compared against expected events. Based on the comparison detecting at least one of the expected events being absent in the sequence chart, providing the optimal global quantum value as being smaller than the provisional global quantum value. Based on the comparison detecting no difference between the events in the sequence chart and the expected events, providing the optimal global quantum value as being larger than the provisional global quantum value.
    Type: Grant
    Filed: September 5, 2012
    Date of Patent: January 8, 2019
    Assignee: Cadence Design Systems, Inc.
    Inventors: Qizhang Chao, Neeti K. Bhatnagar, George F. Frazier, Tuay-Ling Kathy Lang, Andrew Wilmot
  • Patent number: 8838430
    Abstract: An apparatus and method for detecting memory access violations in simulations is disclosed herein. A detection tool is designed to automatically perform a violation check for each memory read or write operation simulated in a modeled system. The detection tool is capable of handling a modeled system including one or more memories and/or one or more processors.
    Type: Grant
    Filed: August 26, 2011
    Date of Patent: September 16, 2014
    Assignee: Cadence Design Systems, Inc.
    Inventors: Tuay-Ling Kathy Lang, Neeti K. Bhatnagar, Jai Bharat Patel Gulabeela, George F. Frazier, Qizhang Chao
  • Publication number: 20140067358
    Abstract: An apparatus and method for determining an optimal global quantum value for use in event-driven simulations of a device are disclosed herein. The device is simulated using information representative of a device design corresponding to the device, the simulation of the device comprising an event-driven simulation using a provisional global quantum value. Events included in a sequence chart corresponding to the simulation using the provisional global quantum value are compared against expected events. Based on the comparison detecting at least one of the expected events being absent in the sequence chart, providing the optimal global quantum value as being smaller than the provisional global quantum value. Based on the comparison detecting no difference between the events in the sequence chart and the expected events, providing the optimal global quantum value as being larger than the provisional global quantum value.
    Type: Application
    Filed: September 5, 2012
    Publication date: March 6, 2014
    Applicant: Cadence Design Systems, Inc.
    Inventors: Qizhang Chao, Neeti K. Bhatnagar, George F. Frazier, Tuay-Ling Kathy Lang, Andrew Wilmot
  • Patent number: 7720665
    Abstract: A system for controlling reset in discrete event simulation is disclosed. The system includes a simulator configured to effect the discrete event simulation, the simulator having a plurality of shared executable files, a memory configured to store the simulator for execution, an operating system having a loading/unloading facility, and a control program configured to effect a reset operation by directing the operating system to unload the simulator from the memory and then reload the simulator into the memory using the loading/unloading facility.
    Type: Grant
    Filed: May 4, 2006
    Date of Patent: May 18, 2010
    Assignee: Cadence Design Systems, Inc.
    Inventors: George Franklin Frazier, Qizhang Chao, Tuay-Ling Kathy Lang, Neeti Khullar Bhatnagar, Andrew Robert Wilmot
  • Patent number: 7069204
    Abstract: A method and system for evaluating performance level models of electronic systems having both hardware and software components is provided. The system and method allow for the simplified implementation and testing of several different architectural designs for compliance with the desired operational requirement of a designed electronic system.
    Type: Grant
    Filed: September 28, 2000
    Date of Patent: June 27, 2006
    Assignee: Cadence Design System, Inc.
    Inventors: Sherry Solden, Edwin A. Harcourt, William W. La Rue, Jr., Douglas D. Dunlop, Christopher Hoover, Qizhang Chao, Poonam Agrawal, Aaron Beverly, Massimiliano L. Chiodo, Neeti K. Bhatnagar, Soumya Desai, Hungming Chou, Michael D. Sholes, Sanjay Chakravarty, Eamonn O'Brien-Strain, Luciano Lavagno