US5081601A
Expired / Lapsed
US
⏱️ 0.0 years remaining
System for combining independently clocked simulators
Assignee: LSI Corp
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Filing: 1989-09-22
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Granted: 1992-01-14
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Expires: 2009-09-22
Abstract
Abstract Two or more independently clocked simulators are interconnected in a manner which prevents signal exchange at a time when the internal simulation clocks of the simulators point to different times on a simulated time line. Each simulator transmits to one or more of the other simulators in its network information indicaitng the next point in simulated time at which the transmitting simulator can model a state change which might affect a model part being simulated by the receiving simulator. Blocking means are provided for blocking the receiving simulator from advancing its simulated time clock ahead of the next state change time of the transmitting simulator. The receiving simulator is free, however, to operate at its maximum speed for simulated time spans occurring before the next state change time of the transmitting simulator.
Inventors
- 👤 Asgeir T. Eirikasson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 00:49
CPC Classifications
G; G06; G06F; G06F8/00; G06F8/40; G06F8/41; G06F8/45; G06F8/458; G06F30/00; G06F30/30; G06F30/32; G06F30/33
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
166 words
A method for interconnecting first and second model parts whose operations are being respectively simulated in independently clocked first and second simulators comprising: determining the next point in simulated time at which the first model part can generate a state which could affect the second model part; transmitting a first value representing the next time point to the second simulator; and blocking the second simulator from simulating an operation in the second model part at a time point later in simulated time than the next time point of the first model part; determining the next point in simulated time at which the second model part can generate a state which could affect the first model part; transmitting a second value representative of the next time point of the second model part to the first simulator; blocking the first simulator from simulating an operation in the first model part at a time point later in simulated time than the next time point of the second model part.
Claim 2
Independent Claim
166 words
A method for interconnecting first and second model parts whose operations are being respectively simulated in independently clocked first and second simulators comprising: determining the next point in simulated time at which the first model part can generate a state which could affect the second model part; transmitting a first value representing the next time point to the second simulator; and blocking the second simulator from simulating an operation in the second model part at a time point later in simulated time than the next time point of the first model part; determining the next point in simulated time at which the second model part can generate a state which could affect the first model part; transmitting a second value representative of the next time point of the second model part to the first simulator; blocking the first simulator from simulating an operation in the first model part at a time point later in simulated time than the next time point of the second model part.
Claim 3
Dependent Claim
19 words
The method of claim 1 wherein at least one of the first and second simulators is an event-driven simulator.
Claim 4
Independent Claim
170 words
A system for simulating an interconnection of first and second model parts whose operations are being respectively simulated in independently clocked first and second simulators, comprising: means for determining a next point in simulated time at which the first model part can generate a state which could affect an operation within the second model part; communication means, coupled to the determining means and the second simulator, for transmitting a first value representative of the next time point of the first model part to the second simulator; means for blocking the second simulator from simulating an operation of the second model part occurring at a time point later in simulated time than the next time point of the first model part, said blocking means not blocking the second simulator from simulating operation of the second model part occurring before the next time point of the first model part; and wherein one of the first and second simulators performs simulations faster than the other simulator for a given level of model definition.
Claim 5
Independent Claim
170 words
A system for simulating an interconnection of first and second model parts whose operations are being respectively simulated in independently clocked first and second simulators, comprising: means for determining a next point in simulated time at which the first model part can generate a state which could affect an operation within the second model part; communication means, coupled to the determining means and the second simulator, for transmitting a first value representative of the next time point of the first model part to the second simulator; means for blocking the second simulator from simulating an operation of the second model part occurring at a time point later in simulated time than the next time point of the first model part, said blocking means not blocking the second simulator from simulating operation of the second model part occurring before the next time point of the first model part; and wherein one of the first and second simulators performs simulations faster than the other simulator for a given level of model definition.
Claim 6
Dependent Claim
19 words
The system of claim 3 wherein at least one of the first and second simulators is an event-driven simulator.
Claim 7
Dependent Claim
43 words
The system of claim 3 wherein the first and second model parts define interconnected parts of a digital system and wherein the level of model definition is selected from the group consisting of a behavioral level, a gate level and a transistor level.
Claim 8
Dependent Claim
18 words
The system of claim 3 wherein the first and second simulators are designed to process imcompatible software libraries.
Claim 9
Independent Claim
122 words
A system for modelling the operations of two or more interconnected parts of a model, comprising: two or more independently clocked simulators each modelling the operations of a respective one of the two or more model parts, wherein each simulator includes: (a) current time designating means for designating a current point in simulated time at which the operations of its respective model part are being currently simulated; (b) next time designating means for designating a next point in simulated time at which the operation of its respective model part is scheduled to be next simulated; and (c) transmission means for transmitting to one or more of the other simulators a value representing the next point in simulated time of the transmitting simulator.
Claim 10
Independent Claim
122 words
A system for modelling the operations of two or more interconnected parts of a model, comprising: two or more independently clocked simulators each modelling the operations of a respective one of the two or more model parts, wherein each simulator includes: (a) current time designating means for designating a current point in simulated time at which the operations of its respective model part are being currently simulated; (b) next time designating means for designating a next point in simulated time at which the operation of its respective model part is scheduled to be next simulated; and (c) transmission means for transmitting to one or more of the other simulators a value representing the next point in simulated time of the transmitting simulator.
Claim 11
Independent Claim
177 words
A system for modelling the operations of two or more interconnected parts of a model, comprising: two or more independently clocked simulators each modelling the operations of a respective one of the two or more model parts, wherein each simulator includes: (a) means for designating a current point in simulated time at which the operations of its respective model part are being currently simulated; (b) designating means for designating a next point in simulated time at which the operation of its respective model part is scheduled to be next simulated; and (c) means for transmitting to one or more of the other simulators a value representing the next point in simulated time of the transmitting simulator; means for receiving from one or more of the other simulators respective other values representing the next time points of the other simulators; and means for blocking advancement of the current time designating means in the receiving simulator if the next time of the receiving simulator is greater than a next time value received from any one of the other simulators.
Claim 12
Independent Claim
177 words
A system for modelling the operations of two or more interconnected parts of a model, comprising: two or more independently clocked simulators each modelling the operations of a respective one of the two or more model parts, wherein each simulator includes: (a) means for designating a current point in simulated time at which the operations of its respective model part are being currently simulated; (b) designating means for designating a next point in simulated time at which the operation of its respective model part is scheduled to be next simulated; and (c) means for transmitting to one or more of the other simulators a value representing the next point in simulated time of the transmitting simulator; means for receiving from one or more of the other simulators respective other values representing the next time points of the other simulators; and means for blocking advancement of the current time designating means in the receiving simulator if the next time of the receiving simulator is greater than a next time value received from any one of the other simulators.
Claim 13
Dependent Claim
22 words
The system of claim 8 wherein at least one of the simulators is an event-driven simulator having a dynamically updated event queue.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-01-13 | 1995-07-15 | 1996-01-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-01-13 | 1999-07-15 | 2000-01-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-01-13 | 2003-07-15 | 2004-01-14 | $7700.00 | Window Closed / Lapsed |