Including Logic Patents (Class 703/15)
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Patent number: 7478029Abstract: A cable simulator that comprises an input device configured to receive a communication signal. The cable simulator further comprises a circuit configured to simulate attenuation in both the differential mode and common mode components of a communication signal.Type: GrantFiled: November 3, 2004Date of Patent: January 13, 2009Assignee: Adtran, Inc.Inventor: Daniel M. Joffe
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Patent number: 7478346Abstract: A synthesizer or emulator processes a gate level IC design derived from an RTL design to produce a gate level dump file indicating how signals of the gate level design behave. The gate level dump file is converted into an RTL dump file indicating how signals of the RTL design behave. A debugger processes the RTL dump file to produce displays depicting the RTL design and behavior of signals indicated by the RTL dump file. Thus while the IC is simulated or emulated at the gate level of the design to produce waveform data for a debugger, the gate level-to-RTL dump file conversion process enables a designer debug the more familiar RTL design based on the gate level simulation or emulation results. file conversion process enables a designer debug the more familiar RTL design based on the gate level simulation or emulation results.Type: GrantFiled: January 26, 2006Date of Patent: January 13, 2009Assignee: Springsoft USA, Inc.Inventors: Yu-Chin Hsu, Furshing Tsai, Wori-Tzy Jong
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Patent number: 7478304Abstract: The present invention provides an apparatus and a computer program product for applying external clock and data patterns for TTP-LBIST. A simulation model for the logic under test is set up in a simulator. Next, a user sets up an external LBIST block, which comprises pre-verified internal clock and data pattern logic, and connects this block to the logic in the simulation model. The internal clock and data pattern logic provides the input patterns used in OPCG modes of LBIST. This internal clock and data pattern logic is already verified through the design effort. Therefore, the internal pattern generators become the external pattern generators in the simulation model. The external LBIST block applies the external clock and data patterns, and subsequently, the user receives and processes these output patterns to determine if the logic operates correctly.Type: GrantFiled: November 8, 2007Date of Patent: January 13, 2009Assignee: International Business Machines CorporationInventors: Tilman Gloekler, Christian Habermann, Naoki Kiryu, Joachim Kneisel, Johannes Koesters
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Publication number: 20090006066Abstract: A system for selecting a test case. A test case with a high score is selected. A simulation job is run on a device under test on a plurality of processors using the selected test case. Simulation performance and coverage data is collected for the selected test case and the collected simulation performance and coverage data is stored in a database.Type: ApplicationFiled: June 28, 2007Publication date: January 1, 2009Inventors: Michael L. Behm, Steven R. Farago, Brian L. Kozitza, John R. Reysa
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Publication number: 20080306722Abstract: There is provided a logic verification system having improved development time and design quality, in which all pins of an FPGA module are wired in direct between the FPGA module and a bridge circuit used in the verification processes of a logic simulator accelerator and a logic emulator, a cutting end of the verification object logic is assigned to an external interface connector of the FPGA module when the logic simulation is accelerated, and the correspondence between each pin of external interface connector of the FPGA module and logic signal is performed on the logic simulator on the general purpose processor.Type: ApplicationFiled: February 8, 2008Publication date: December 11, 2008Inventors: Mototsugu Fujii, Osamu Tada, Kazunobu Morimoto, Akira Yamagiwa, Hisashi Nanao
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Patent number: 7464015Abstract: In a verification supporting apparatus, when an obtaining unit obtains a verification scenario, a substituting unit substitutes an undefined value for a variable value in the verification scenario. A first executing unit executes a logic simulation using an input pattern. From a result of the logic simulation, a determining unit generates code-coverage upper-limit information. A setting unit sets input patterns by giving an arbitrary logic value to the variable value. A second executing unit executes a logic simulation using the input patterns set. A generating unit generates code coverage from the input patterns set. A calculating unit calculates a level of achievement of the code coverage with respect to the code-coverage upper-limit information.Type: GrantFiled: April 28, 2005Date of Patent: December 9, 2008Assignee: Fujitsu LimitedInventor: Hiroaki Iwashita
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Patent number: 7464287Abstract: Various embodiments of the invention provide a frequency shifter to vary the frequency of data transmitted over time, such as to increase and decrease the frequency of test data transmitted over time to verify a digital communication device's ability to receive data having various frequencies within a specific parameter range. The frequency shifter includes a frequency modifier to shift or vary an input clock frequency to a variety of output clock frequencies, such as according to a test protocol. The frequency shifter also includes an elastic data buffer to receive the test data at the input clock frequency and to output the test data at the plurality of output clock frequencies provided by the frequency modifier.Type: GrantFiled: March 31, 2004Date of Patent: December 9, 2008Assignee: Intel CorporationInventors: Debendra Das Sharma, Gurushankar Rajamani, Hanh Hoang
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Publication number: 20080300849Abstract: A system and method for simulating a circuit design using both an unknown Boolean state and a negative unknown Boolean state is provided. When the circuit is simulated, one or more initial simulated logic elements are initialized to the unknown Boolean state. The initialized unknown Boolean states are then fed to one or more simulated logic elements and the simulator simulates the handling of the unknown Boolean state by the simulated logic elements. Examples of simulated logic elements include gates and latches, such as flip-flops, inverters, and basic logic gates. The processing results in at least one negative unknown Boolean state. An example of when a negative unknown Boolean state would result would be when the unknown Boolean state is inverted by an inverter. The resulting negative unknown Boolean state is then fed to other simulated logic elements that generate further simulation results based on processing the negative unknown Boolean state.Type: ApplicationFiled: August 15, 2008Publication date: December 4, 2008Applicant: International Business Machines CorporationInventor: Richard Nicholas
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Patent number: 7460988Abstract: There is provided a test emulator for emulating a test apparatus including a plurality of test modules for supplying test signal to devices under test respectively, including: a plurality of test module emulation sections for emulating the plurality of test modules generating the test signal based on different cycles, a control emulation section for emulating a control apparatus for controlling the test of the devices under test, a synchronous emulation section for generating test signal generating timings, at which each of the plurality of test module emulation sections is to generate the test signal in simulation corresponding to cycle time of the test module emulation section, based on instructions from the control emulation section, a timing alignment section for aligning the plurality of test signal generating timings generated by the synchronous emulation section in order of time, and outputting them one by one, and a schedule section for causing the test module emulation section corresponding to one ofType: GrantFiled: March 31, 2003Date of Patent: December 2, 2008Assignee: Advantest CorporationInventor: Shinsaku Higashi
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Publication number: 20080294412Abstract: A design structure for performing cacheline polling utilizing store and reserve and load when reservation lost instructions is disclosed. In one embodiment a method is provided which comprises storing a buffer flag busy indicator data value within a first cacheable memory location and setting a load/store operation reservation on said first cacheable memory location via a store and reserve instruction. In the described embodiment, a data value stored within the first cacheable memory location is accessed via a conditional load instruction in response to a determination that the load/store operation reservation on the first cacheable memory location has been reset. Conversely, execution of the conditional load instruction is stalled in response to a determination that the load/store operation reservation on the first cacheable memory location has not been reset.Type: ApplicationFiled: June 3, 2008Publication date: November 27, 2008Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATIONInventor: CHARLES R. JOHNS
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Publication number: 20080294411Abstract: Methods and systems for simulating logic may translate logic design into executable code for a multi-processor based parallel logic simulation device. A system may implement one or more parallel execution methods, which may include IPMD, MPMD, and/or DDMT.Type: ApplicationFiled: November 9, 2007Publication date: November 27, 2008Applicant: ET INTERNATIONAL, INC.Inventors: Guang R. Gao, Fei Chen
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Publication number: 20080288231Abstract: A cooperation verifying apparatus includes a storage unit and a processing unit. The processing unit simulates a software-based portion and a hardware-based portion in a target system, issues instruction signals from the software-based portion to the hardware-based portion in order during the simulation, stores a data of a progress state of the simulation of the software-based portion in the storage unit, stores the instruction signals in an order of reception as an input history in the storage unit and associates the input history with the progress state data.Type: ApplicationFiled: May 12, 2008Publication date: November 20, 2008Applicant: NEC Electronics CorporationInventor: Isamu Nakayama
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Patent number: 7454323Abstract: Method and apparatus for security systems are provided to protect electronic designs from unauthorized usage. An obfuscation system is provided for creating secure simulation models of IP cores that allow efficient evaluation of an electronic design incorporating an IP core but do not allow practical implementation of the IP core. The obfuscation system identifies regions for obfuscation within an IP core. Logic obfuscation is inserted into these regions. Examples of obfuscation include additional circuitry that produces time dilatation, space dilatation, or a combination of the two in the circuitry of an IP core. Typically, the inserted obfuscation does not change the ultimate behavior of the internal signals, but is complicated enough to make an electronic design so slow and/or so large that it cannot be implemented practically. Further, the inserted obfuscation should be of a type is not normally removed by that normal logic optimizations such as synthesis.Type: GrantFiled: August 22, 2003Date of Patent: November 18, 2008Assignee: Altera CorporationInventor: Peter Bain
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Patent number: 7454325Abstract: According to one method of simulation processing, a count event counter for a count event is created within instrumentation of a hardware description language (HDL) simulation model of a design and a threshold greater than 1 is established for the count event counter. The design is then simulated utilizing the HDL simulation model, and occurrences of the count event are accumulated in the count event counter to obtain a count event value. Thereafter, an indication of whether the count event value of the count event exceeds the threshold is recorded within a data storage subsystem.Type: GrantFiled: December 7, 2004Date of Patent: November 18, 2008Assignee: International Business Machines CorporationInventors: Michael Lee Behm, Carol Ivash Gabele, Wolfgang Roesner, Derek Edward Williams
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Publication number: 20080281571Abstract: According to a method of simulation processing, a collection of files including one or more HDL source files describing design entities collectively representing a digital design to be simulated is received. The HDL source file(s) include a statement specifying inclusion of an instrumentation entity not forming a portion of the digital design but enabling observation of its operation during simulation. The instrumentation entity includes sequential logic containing at least one storage element, where the instrumentation entity has an output signal indicative of occurrence of a simulation event. The collection of files is processed to obtain an instrumented simulation executable model. The processing includes instantiating at least one instance of each of the plurality of design entities and instantiating the instrumentation entity. The processing further includes instantiating external instrumentation logic, logically coupled to each instance of the instrumentation entity, to record occurrences of the event.Type: ApplicationFiled: May 7, 2007Publication date: November 13, 2008Inventors: Wolfgang Roesner, Derek E. Williams
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Patent number: 7451426Abstract: An application specific configurable logic IP module includes (1) a system level configuration controller; (2) at least one standardized interconnect communicatively coupled to the system level configuration controller; (3) at least one standardized configuration port for programming the application specific configurable logic IP module; (4) an embedded programmable logic fabric, communicatively coupled to the system level configuration controller and the at least one standardized interconnect, for mapping arithmetic functions into standard cells; (5) at least one scalable configurable logic module; and (6) a programmable routing matrix. The system level configuration controller is suitable for selecting a standard for the at least one standardized interconnect, the at least one standardized configuration port, and a number of embedded programmable logic functions, and for controlling the programmable routing matrix.Type: GrantFiled: July 7, 2005Date of Patent: November 11, 2008Assignee: LSI CorporationInventor: Claus Pribbernow
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Patent number: 7447620Abstract: Asynchronous behavior of a circuit is emulated by modifying a netlist to insert additional logic at a driving element such as a latch. The additional logic outputs one of (i) a present output from the driving element, (ii) a delayed output from the driving element, or (iii) a random value, which drives downstream logic. The output of the additional logic is selectively responsive to a user-controlled skew enable input. The invention allows for simpler data skew logic transformations which are applicable to both latches and primary inputs, with no dependencies on any clock net.Type: GrantFiled: February 23, 2006Date of Patent: November 4, 2008Assignee: International Business Machines CorporationInventors: Zoltan T. Hidvegi, Yee Ja, Bradley S. Nelson
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Patent number: 7447966Abstract: Exemplary techniques for verifying a hardware design are described. In a described embodiment, a method comprises compiling an error verification object corresponding to an error verification command to verify a portion of a hardware design of a device under test. The error verification object is compiled in accordance with data provided by an error scripting module. The error scripting module has access to hardware-specific data corresponding to the hardware design of the device under test. The compiled object is sent to the device under test and a response to the compiled object is received from the device under test. The received response from the device under test is parsed in accordance with data provided by the error scripting module.Type: GrantFiled: January 5, 2005Date of Patent: November 4, 2008Assignee: Hewlett-Packard Development CompanyInventors: Anand V. Kamannavar, Nathan Dirk Zelle, Bradley Forrest Bass, Sahir Shiraz Hoda, Erich Matthew Gens
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Patent number: 7444276Abstract: A logic simulation processor stores in a shift register intermediate values generated during the logic simulation. The simulation processor includes multiple processor units and an interconnect system that communicatively couples the processor units to each other. Each of the processor units includes a processor element configurable to simulate at least a logic gate, and a shift register associated with the processor element. The shift register includes multiple entries to store the intermediate values, and is coupled to receive the output of the processor element. Each of the processor units further includes one or more multiplexers for selecting one of the entries of the shift register as outputs to be coupled to the interconnect system. Each of the processor units may further include a local memory for storing data from, and loading the data to, the simulation processor.Type: GrantFiled: September 28, 2005Date of Patent: October 28, 2008Assignee: Liga Systems, Inc.Inventors: William Watt, Henry T. Verheyen
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Patent number: 7444574Abstract: A method and system that utilizes a graphical interface that enables a user to select and capture building blocks of a Device Under Test (DUT) test scenario from a previously run test case or from multiple stimulation results. Each of these extracted building block events or “tags” are created from a slice of a graphical stimulation view, which slice is converted into a coded stimulus written in a high-level language code that represents the condition(s) that created the graphical simulation view. These coded stimuli (representing the tags) are stored in a library. To create a corner case scenario or sequence in the DUT, a user utilizes a graphical interface to select the different extracted tags from the library and combines them together.Type: GrantFiled: February 24, 2005Date of Patent: October 28, 2008Assignee: International Business Machines CorporationInventors: Maureen Terese Davis, Katherine Ann Dunning, Tony Emile Sawan
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Publication number: 20080256404Abstract: A fault location estimation system comprises single-fault-assumed diagnostic means that assumes a single fault and stores fault candidates, fault types, and detected error-observation nodes at which an error arrives from the fault candidates; error-observation node basis candidate classification means that classifies error propagating fault candidates into groups according to error-observation nodes using the fault candidates and the error-observation nodes and stores the groups as fault candidate groups; inclusion fault candidate group selection means that acquires a relation between each fault candidate group and a fault output, calculates an inclusion relation among the fault candidate groups, and, if path information on one fault candidate group includes path information on another fault candidate group, deletes the inclusion fault candidate group; inter-pattern overlapping means that calculates combinations of fault candidate groups that can reproduce a test result in all test patterns by referencing theType: ApplicationFiled: October 4, 2007Publication date: October 16, 2008Applicant: NEC ELECTRONICS CORPORATIONInventor: Yukihisa FUNATSU
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Publication number: 20080255821Abstract: In at least one hardware definition language (HDL) file, at least one design entity containing a functional portion of a digital system is specified. The design entity logically contains first and second latches each having a respective plurality of different possible latch values. With one or more statements, a first Dial instance is associated with the first latch and a second Dial instance is associated with the second latch. A setting of the first Dial instance thus controls which of the plurality of different possible values is loaded in the first latch, and a setting of the second Dial instance controls which of the plurality of different possible values is loaded in the second latch. With a statement, a Register instance is concurrently associated with both the first and the second latches, such that a setting of the Register instance controls the latch values loaded in both the first and second latches.Type: ApplicationFiled: June 25, 2008Publication date: October 16, 2008Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATIONInventors: Wolfgang Roesner, Derek Edward Williams
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Patent number: 7433808Abstract: In an embodiment, a computer-implemented method for modeling a system using a finite state machine representation is presented. An event-driven temporal logic operator may be associated with a first, active state in the finite state machine representation. A value of the temporal logic operator may be determined by a number of occurrences of an event during an existing activation of the first state associated with the temporal logic operator. A state transition from the first state to a second state may be executed based on the value of the temporal logic operator. The second state may be set as the active state.Type: GrantFiled: January 10, 2006Date of Patent: October 7, 2008Assignee: The MathWorks, Inc.Inventors: Vijay Raghavan, Ebrahim Mehran Mestchian
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Patent number: 7433812Abstract: A modeling process includes providing blocks, each of the blocks representing functional entities that operate on input signal values, output signal values from the blocks, grouping the output signal values as an ordered set in a multiplexer as a first composite signal and outputting the first composite signal.Type: GrantFiled: May 30, 2001Date of Patent: October 7, 2008Assignee: The MathWorks, Inc.Inventors: Mojdeh Shakeri, Marc Ullman, Ramamurthy Mani
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Publication number: 20080243462Abstract: A hardware simulation accelerator to simulate logic designs, a method to encode instructions for use in the hardware simulation accelerator, and a computer program product having code of the method by which the hardware simulation accelerator can read encoded instructions to simulate the logic design, and computer program product of the encoded instructions to simulate a logic design in a hardware accelerator. Each instruction has one of a plurality of opcodes, the opcodes select which of the hardware resources of the hardware simulation accelerator will implement and use the values set forth in other programmable bits of the encoded instruction. The encoded instruction may be a routing and/or a gate evaluation instruction.Type: ApplicationFiled: March 30, 2007Publication date: October 2, 2008Applicant: International Business Machines CorporationInventors: Gernot E. Guenther, Viktor Gyuris, Kevin Anthony Pasnik, Thomas John Tryt, John H. Westermann
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Patent number: 7430502Abstract: Systems, methodologies, media, and other embodiments associated with simulating a processor performance state by controlling a thermal management signal are described. One exemplary system embodiment includes a data structure for storing bit patterns that facilitate controlling a GPIO (General Purpose Input Output) block and addresses of locations to which the bit patterns can be written. The example system may also include a logic configured to receive a request to produce a performance state in a processor and to cause a frequency and voltage to be established in the processor in response to a thermal management signal being generated in response to writing the bit pattern(s) to the address(es).Type: GrantFiled: March 29, 2004Date of Patent: September 30, 2008Assignee: Hewlett-Packard Development Company, L.P.Inventor: Louis B. Hobson
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Patent number: 7428484Abstract: Provided are an apparatus and method for modeling and analyzing a network simulation for a salable simulation framework (SSF)-based network simulation package. A system logic set is generated and a network simulation modeling suitable for a predetermined network application is formed according to the system logic set. The network simulation modeling is transmitted to a predetermined network simulation package that performs simulation. Statistical information is generated based on the result according to the system logic set. Complicated network simulation modeling errors can be minimized, and remodeling of the network simulation modeling can be reduced.Type: GrantFiled: February 4, 2005Date of Patent: September 23, 2008Assignee: Electronics and Telecommunications Research InstituteInventors: Sung Hyun Yun, Moon Kyun Oh, Kyung Jun Park, Yong Mun Park, No Ik Park
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Patent number: 7426704Abstract: Testing a model of a logic circuit model. The testing includes generating valid random input stimulus sequences for a logic circuit model. Enumerating critical resource requirements, enumerating critical resource availabilities does this, and selecting of stimulus sequences and determining legal times for execution of said stimulus sequences based on resource availability. This includes generating a plurality of possible combinations of input stimulus sequences and generating an array representation of critical resource requirements. These are used to generate an array representation of critical resources availabilities.Type: GrantFiled: May 10, 2004Date of Patent: September 16, 2008Assignee: International Business Machines CorporationInventors: Faisal A. Ahmad, Kevin C. Gower, Anish T. Patel
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Patent number: 7424417Abstract: A method and system are disclosed, in a simulation of a design of a digital integrated circuit chip, to limit a number of scan test clocks and chip ports used for testing the chip. Clock domains are identified within the design of the chip that are independent of each other. The independent clock domains are grouped together, within said chip design, to form clock domain groups. A timing analysis is performed on the design of the chip by clocking the clock domain groups each with an independent scan test clock. The scan test clocks originate externally to the design and by-pass, within the chip design, the corresponding internal clocks. Capture mode violations are recorded from the timing analysis and are used to go back and form new clock domain groups, thereby repeating the method until no capture mode violations are generated.Type: GrantFiled: November 19, 2002Date of Patent: September 9, 2008Assignee: Broadcom CorporationInventor: Amar Guettaf
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Publication number: 20080215305Abstract: A first software program executing on a computing device emulates a second computing device executing a software program using emulated memory. The first software program permits the second software program to perform an operation on a contiguous portion of the emulated memory only when a pointer and a table entry both contain the same identifier, thus protecting against common types of memory usage errors in the second software program. The pointer has an address to the contiguous portion. The table entry maps to the contiguous portion. A plurality of table entries map to a respective plurality of contiguous portion of the emulated memory. A plurality of the pointers each contain the address to a respective contiguous portion of the emulated memory as well as containing an identifier corresponding to the respective contiguous portion of the emulated memory. The second computing device can be high or low in resources.Type: ApplicationFiled: April 16, 2008Publication date: September 4, 2008Applicant: Microsoft CorporationInventors: Alan G. Bishop, Landon Dyer, Martin Taillefer
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Publication number: 20080208555Abstract: A simulation method and apparatus including a restore point setting unit setting restore points in core models for executing threads using parallel processing. The method also includes storing information for reproducing a state the core models at the restore points.Type: ApplicationFiled: February 26, 2008Publication date: August 28, 2008Inventors: Masato Tatsuoka, Atsushi Ike
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Publication number: 20080208556Abstract: A pin-based memory power modeling method using arc-based characterization includes steps as follows. All power arcs of a memory model are identified and characterized. A power arc is selected from the identified and characterized power arcs. Output bus switching power is computed by removing overlapping power using the selected power arc, and a temporary value for various input ramp times and output loads is derived. Output pin power for the selected power arc is calculated using the temporary value and a ratio of a number of output bits switching over an entire bus width. Switching power for the selected power arc is calculated by a power estimation tool based on port activity and an input intrinsic power value.Type: ApplicationFiled: May 1, 2008Publication date: August 28, 2008Inventors: Jia-Lih J. Chen, Naveen Gupta, Ghasi R. Agrawal
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Publication number: 20080201128Abstract: A method and system for performing ternary verification is disclosed. Initially, a ternary model is generated from a binary model of a logic circuit design. The pairings used to encode the ternary model are then recorded. Next, the number of the recorded gate pairings is reduced by removing all invalid gate pairings. A ternary verification is performed on the ternary model having a reduced number of gate pairings.Type: ApplicationFiled: February 16, 2007Publication date: August 21, 2008Inventors: Jason R. Baumgartner, Hari Mony, Viresh Paruthi, Matyas A. Sustik
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Patent number: 7412695Abstract: Sequential digital integrated circuits have stable state nodes that are capable of retaining their state (logic value) even in the absence of any input directly driving these points. However, in addition to stable state nodes, some custom-designed digital circuits have so-called transient state nodes. A transient state node is defined as node that can directly affect the value of a stable state node and is combinatorially driven by inputs of the circuit, but the transition delay from at least one input to the node is greater than a predefined threshold value. Identifying such transient state nodes, along with the stable state nodes, is critical for the efficient simulation of custom digital circuits by a hierarchical device level digital simulator. A method is provided herein for identifying transient state nodes in a digital circuit, given the circuit's netlist and the identity of the stable state nodes in the circuit.Type: GrantFiled: August 17, 2005Date of Patent: August 12, 2008Assignee: National Semiconductor CorporationInventors: Tathagato Rai Dastidar, Amir Yashfe, Partha Ray
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Patent number: 7409331Abstract: A method for designing an integrated circuit having analog and digital circuit portions is disclosed. The method involves providing an emulation circuit, which preferably comprises a number of gates equivalent to a number of gates in the digital circuit portion, affixing the emulation circuit on a test substrate together with a version of the analog circuit portion having at least some of the defined functions of the analog circuit portion, and then testing the analog circuit version.Type: GrantFiled: August 2, 2005Date of Patent: August 5, 2008Assignee: Broadcom CorporationInventor: Vikram Gupta
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Publication number: 20080184150Abstract: One or more technologies described herein can be used for viewing results of a simulation of a software executable in a multi-processor electronic circuit design. A debug environment can display simulation results related to the multiple processors, for example, as a correlated software debug view of the processors. In at least some embodiments, the disclosed technologies can be used to examine a correlation between an error in the design which is shown in the simulation results and one or more inter-processor synchronization events.Type: ApplicationFiled: October 30, 2007Publication date: July 31, 2008Inventors: Marc Minato, Russell Alan Klein
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Publication number: 20080177524Abstract: There is provided with simulation execution apparatus including: a receiving unit configured to receive a cyclic signal; registers; a simulation execution unit configured to execute simulation of a logic circuit model which operates with the use of the cyclic signal and the registers; a counter configured to count time based on the cyclic signal; a register value monitoring unit configured to monitor the values of the registers; a register data recording unit configured to record in a storage, register data made up of the values of the registers in association with the time of the counter when the value of at least one of the registers is changed; a cyclicity detection unit configured to detect a cyclicity of the register data based on the storage; and a stop unit configured to give a stop instruction signal which instructs stop of the simulation execution to the simulation execution unit.Type: ApplicationFiled: November 16, 2007Publication date: July 24, 2008Applicant: KABUSHIKI KAISHA TOSHIBAInventor: Tomoshi Otsuki
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Patent number: 7398445Abstract: A method and system for debug and test using replicated logic is described. A representation of a circuit is compiled. The circuit includes a replicated portion and delay logic to delay inputs into the replicated portion. The circuit may also include trigger logic and clock control logic to enable execution of the replicated portion of the circuit to be paused when a trigger condition occurs. The compiled representation of the circuit may be programmed into a hardware device. A debugger may then be invoked. One or more triggering signals are selected. For each selected triggering signal, one or more states are selected to setup a trigger condition. The hardware device may then be run. The replicated portion of the circuit will be paused when the trigger condition occurs. The states of registers in the replicated portion of the circuit and the sequence of inputs that led to the trigger condition are recorded.Type: GrantFiled: August 2, 2005Date of Patent: July 8, 2008Assignee: Synplicity, Inc.Inventors: Chun Kit Ng, Mario Larouche
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Patent number: 7395197Abstract: A shared register row is provided between a program-based circuit simulator and a device-based circuit simulator. The shared register row includes a plurality of shared registers each corresponding to signals transmitted between the program-based and device-based circuit simulators. By mutually accessing a shared register corresponding to a signal from the program-based and device-based circuit simulators, the signal is transferred via the corresponding shared register with synchronization between the program-based and device-based circuit simulators.Type: GrantFiled: September 8, 2004Date of Patent: July 1, 2008Assignee: NEC CorporationInventor: Yuichi Nakamura
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Patent number: 7392171Abstract: A computer based test bench generator (1) for verifying integrated circuits specified by models in a Hardware Description Language includes a repository (10) storing a general set of self-checking tests applicable to the integrated circuits. A capability is provided for entering behavior data (21) of an integrated circuit model (20), and for entering configuration data (22) of the integrated circuit model. The generator automatically generates test benches (30) in the Hardware Description Language by making a selection and setup of suitable tests from the repository according to the specified integrated circuit model, configuration and behavior data.Type: GrantFiled: June 24, 2003Date of Patent: June 24, 2008Assignees: STMicroelectronics S.r.l., STMicroelectronics LimitedInventors: Gianluca Blasi, Reenee Tayal
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Patent number: 7392168Abstract: A computer system reads data corresponding to an IC layout target layer and performs an etch simulation on the target layer. Etch biases are calculated and the inverse of the etch biases are used to produce a new target layer. The new target layer is provided as an input to an optical process correction (OPC) loop that corrects the data for image/resist distortions until a simulation indicates that a pattern of objects created on a wafer matches the new target layer. In another embodiment of the invention, original IC layout data is provided to both the OPC loop and an etch simulation. Etch biases calculated by the etch simulation are used in the OPC loop in order to produce mask/reticle data that will be compensated for both optical and resist distortions as well as for etch distortions.Type: GrantFiled: July 2, 2001Date of Patent: June 24, 2008Inventors: Yuri Granik, Franklin M. Schellenberg
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Publication number: 20080147359Abstract: A system for designing a circuit, which includes a module, uses a computer. A user may program or adapt the computer to perform computer-aided design functions. The computer obtains a description of the module from the user. The computer parses the description of the module to identify a port of the module, and to obtain information about the port. The computer presents to the user the information that it has obtained about the port.Type: ApplicationFiled: August 15, 2007Publication date: June 19, 2008Applicant: ALTERA CORPORATIONInventors: James M. Brown, Tim Allen, Mike Fairman, Jeffrey O. Pritchard
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Patent number: 7386814Abstract: Translation of high-level design blocks into a design specification in a hardware description language (HDL). Each block in the high-level design is assigned to a group. A set of attributes is identical between the blocks in a group. For each group of blocks, a respective set of parameters having different values on subblocks of at least two blocks in the group is determined. An HDL specification is generated for each group. The HDL specification for a group has for each parameter in the set of parameters, a parameter input.Type: GrantFiled: February 10, 2005Date of Patent: June 10, 2008Assignee: Xilinx, Inc.Inventors: Jeffrey D. Stroomer, Roger B. Milne, Isaac W. Foraker, Sean A. Kelly
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Patent number: 7385383Abstract: Methods and systems are provided for determining efficacy of stress protection circuitry. The methods and systems employ a ring oscillator that models at least one parameter of a functional circuit to be protected by the stress protection circuit. A stress signal is applied to the ring oscillator and parametric degradation is measured to determine the effectiveness of the stress protection circuit in protecting the ring oscillator. A stress signal can be a voltage or current that stresses the normal operation of a functional circuit. The parametric degradation of the ring oscillator can be correlated to the parametric degradation that would be experienced by the functional circuit.Type: GrantFiled: June 3, 2005Date of Patent: June 10, 2008Assignee: Texas Instruments IncorporatedInventors: Vijay Kumar Reddy, Gianluca Boselli, Jeremy Charles Smith
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Publication number: 20080133205Abstract: A method for compliance testing of a circuit design that includes at least one processor and a memory includes defining a memory model. The memory model includes synchronization mechanisms for synchronizing access to the memory by software instructions in different program threads running on the at least one processor. Synchronization-related parameters, which are applicable to at least one sequence of the software instructions in the different program threads, are specified. A coverage model is defined as a multi-dimensional cross-product of values of the synchronization-related parameters. At least one test program is generated using the coverage model, and a compliance of the design with the memory model is tested by subjecting the design to the at least one test program.Type: ApplicationFiled: November 29, 2007Publication date: June 5, 2008Applicant: International Business Machines CorporationInventors: Allon Adir, Sigal Asaf
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Publication number: 20080133206Abstract: A system and method for verifying an integrated circuit design is provided. The system comprising: an I/O controller connected to one or more I/O cores, the I/O cores part of the integrated circuit design; an external memory mapped test device having a switch for selectively connecting one or more of the I/O cores to corresponding I/O driver models; a bus for transferring signals between the I/O controller and the switch; and a test operating system for controlling the switch.Type: ApplicationFiled: January 7, 2008Publication date: June 5, 2008Inventors: Robert J. Devins, Robert D. Herzl, David W. Milton
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Patent number: 7383166Abstract: A method of checking correctness of scheduling of a circuit where a schedule for the circuit is obtained from a behavioral description. The method comprising extracting loop invariants to determine a sufficient set of acyclic threads when loops are present, performing symbolic simulation to extract the above loop invariants, and proving equivalence of the acyclic threads. Systems, computer systems and computer program products that incorporate the techniques of verification and correctness checking according to the present invention have also been disclosed.Type: GrantFiled: January 14, 2004Date of Patent: June 3, 2008Assignee: NEC CorporationInventors: Pranav Ashar, Anand Raghunathan, Subhrajit Bhattacharya
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Publication number: 20080126065Abstract: A system and method for simulating a circuit design using both an unknown Boolean state and a negative unknown Boolean state is provided. When the circuit is simulated, one or more initial simulated logic elements are initialized to the unknown Boolean state. The initialized unknown Boolean states are then fed to one or more simulated logic elements and the simulator simulates the handling of the unknown Boolean state by the simulated logic elements. Examples of simulated logic elements include gates and latches, such as flip-flops, inverters, and basic logic gates. The processing results in at least one negative unknown Boolean state. An example of when a negative unknown Boolean state would result would be when the unknown Boolean state is inverted by an inverter. The resulting negative unknown Boolean state is then fed to other simulated logic elements that generate further simulation results based on processing the negative unknown Boolean state.Type: ApplicationFiled: September 14, 2006Publication date: May 29, 2008Inventor: Richard Nicholas
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Publication number: 20080126066Abstract: A method for digital circuit design. The first step of the process is the step of providing a circuit design in the form of a hardware definition language. Then, the process produces a binary simulation of the design by setting out for each unit of time during execution of the hardware design the a control state and a program state of the design and assigns a symbol to each signal of the design. The process proceeds by executing a symbolic simulation of the design, concluding with identifying and capturing the combinational logic expression of the simulation output and the next state functions of the simulation.Type: ApplicationFiled: November 2, 2006Publication date: May 29, 2008Applicant: SYNOPSYS, INC.Inventors: Yunshan Zhu, James Herbert Kukula, Robert F. Damiano, Joseph T. Buck
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Patent number: 7379861Abstract: An improved emulation system having an improved trigger mechanism is disclosed. During the compilation of the circuit design, a portion of the emulation resources are reserved for dynamic netlists. The dynamic netlists allows a user to create arbitrary trigger circuits that can be based on any signal generated by the device under test during run time, including signals that were optimized out of the design during the compilation process. The dynamic netlists can be loaded and used in the emulator without having to recompile the entire design, which could take many hours. This enables a user to quickly and efficiently debug circuit designs.Type: GrantFiled: May 19, 2005Date of Patent: May 27, 2008Assignee: Quickturn Design Systems, Inc.Inventors: Alon Kfir, Viktor Salitrennik