Method of cell characterization in a distributed simulation system

• US 5,519,848 A
• Filed: 11/18/1993
• Issued: 05/21/1996
• Est. Priority Date: 11/18/1993
• Status: Expired due to Term

• Current Assignee: Freescale Semiconductor, Inc. (NXP Semiconductors NV)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Tyler, Sean C., Wloka, Markus G., George, Binay J.
• Primary Examiner(s): Teska, Kevin J.
• Assistant Examiner(s): LOUIS JACQUES, JACQUES H
• Application Number:
  US08/154,054
• Time in Patent Office: 915 Days
• Field of Search: 395/500, 395/124, 395/127, 395/800, 395/550, 395/280, 395/183.09, 395/650, 395/900, 395/916, 395/700, 395/184.01, 395/375, 364/DIG. 1, 364/DIG. 2, 364/578, 364/140, 364/481, 364/488-491, 364/724.12, 364/264, 364/401, 364/716, 364/132
• US Class Current: 703/13
• CPC Class Codes: G06F 30/33 Design verification, e.g. functional simulation or model checking
• CPC Class Codes: G06F 30/367 Design verification, e.g. using simulation, simulation program with integrated circuit emphasis [SPICE], direct methods or relaxation methods

Abstract

A method executed by a computer program performs cell characterization in a distributed simulation system by partitioning characterization tasks into individual simulations. A simulation job is generated based on the individual simulations and placed into a simulation job queue. The simulation job queue is copied into a database. The simulation job is accessed and processed in a remote simulator. The remote simulator returns a simulation status and simulation results which are placed into an acknowledge queue. The simulation process is repeated upon detecting an error condition from the simulation status. The simulation status is read from the acknowledge queue and the acknowledge queue is copied into the database.

Claims

1. A computer implemented method of cell characterization in a distributed simulation system, comprising the steps of:

partitioning characterization tasks into individual simulations;

partitioning characterization tasks by cell libraries;

partitioning said characterization tasks within one of said cell libraries by input/output vectors;

partitioning said characterization tasks within said one of said cell libraries and within one of said input/output vectors by parameter assignments;

generating a simulation job based on said individual simulations and said cell libraries;

placing said simulation job into a simulation job queue;

accessing said simulation job and processing said simulation job in a remote simulator;

returning simulation status and simulation results from said remote simulator;

placing said simulation status and simulation results into an acknowledge queue;

reading said simulation status and results from said acknowledge queue;

copying said acknowledge queue into said database; and

post-processing said simulation results.

2. The method of claim 1 further including the step of copying said job queue into a database.

3. The method of claim 2 further including the steps of:

reading said simulation job from said database upon detecting a simulation error; and

placing said simulation job into said simulation job queue.

4. The method of claim 3 further including the steps of:

reading said simulation job from said database upon detecting a system interrupt; and

placing said simulation job into said simulation job queue.