Method and apparatus for encoding and generating transaction-based stimulus for simulation of VLSI circuits

Abstract

The invention comprises a method and system for encoding and generating transaction-based stimuli event states for the eventual application to the simulation of VLSI circuits. In the invention, each test state input is described by a vector where that vector is characterized by two symbols. The first symbol is the “stride” which references its relative time of reoccurrence among the test state inputs. The second symbol denotes the specific transaction on that stride. The stride is a number that is incommensurate relative to the other strides of the transactions.

1 - 20 . (canceled)  
   
   
       21 . A method for testing a device using a plurality of transactions for simulation, the method comprising the steps of: 
 providing a plurality of numbers, wherein any one of the plurality is incommensurable to at least one other of the plurality;    associating each transaction of the plurality of transactions to one of the plurality of numbers;    engaging each transaction to the device at a particular simulation time that is based on the associated number of each transaction; and    repeating the step of engaging for each transaction when the simulation time is an integer multiple of its associated number.    
   
   
       22 . The method of  claim 21  wherein a portion of the plurality of transactions form a test case, and the step of engaging comprises the steps of: 
 looking up the test case in a table of test case entries;    locating a list of transactions associated with the test case;    looking up each transaction of the list of transaction in a table of transactions;    locating information associated with each transaction in the table; and    invoking a function for each transaction based on the information.    
   
   
       23 . The method of  claim 22  further comprising the step of: 
 invoking an emulator, via the function, to issue a command to the device based on the transaction.    
   
   
       24 . The method of  claim 21  wherein the step of repeating comprises the steps of: 
 storing the particular simulation time in a memory;    calculating a subsequent particular simulation time by adding one of the plurality of incommensurable numbers to the particular simulation time; and    storing the subsequent particular simulation time after completion of the step of engaging.    
   
   
       25 . The method of  claim 21  further comprising the step of: 
 incrementing a counter to represent the simulation time.    
   
   
       26 . The method of  claim 21  further comprising the step of: 
 selecting the plurality of incommensurable numbers as non-identical prime numbers from the integers between n 1  and n 2 , wherein n 2  is greater than n 1 .    
   
   
       27 . A system for testing a device using a plurality of transactions for simulation comprising: 
 means for providing a plurality of numbers, wherein any one of the plurality is incommensurable to at least one other of the plurality;    means for associating each transaction of the plurality of transactions to a respective number of the plurality of numbers;    means for engaging each transaction to the device at a particular simulation time that is based on the associated number of each transaction; and    means for repeating the means for engaging for each transaction when the simulation time is an integer multiple of its associated number.    
   
   
       28 . The system of  claim 27  wherein a portion of the plurality of transactions form a test case, and the means for engaging comprises: 
 means for looking up the test case in a table of test case entries and locating a list of transactions associated with the test case;    means for looking up each transaction of the list of transaction in a table of transactions and locating information associated with each transaction in the table; and    means for invoking a function for each transaction based on the information.    
   
   
       29 . The system of  claim 28  further comprising: 
 means for invoking an emulator, via the function, to issue a command to the device based on the transaction.    
   
   
       30 . The system of  claim 27  wherein the means for repeating comprises: 
 means for storing the particular simulation time in a memory;    means for calculating a subsequent particular simulation time by adding one of the plurality of incommensurable numbers to the particular simulation time; and    means for storing the subsequent particular simulation time after operation of the means for engaging.    
   
   
       31 . The system of  claim 27  further comprising: 
 a counter to represent the simulation time.    
   
   
       32 . The system of  claim 27  further comprising: 
 means for selecting the plurality of incommensurable numbers as non-identical prime numbers from the integers between n 1  and n 2 , wherein n 2  is greater than n 1 .    
   
   
       33 . A computer program product having a computer readable medium having computer program logic recorded thereon for testing a device using a plurality of transactions for simulation, the computer program product comprising: 
 code for providing a plurality of numbers, wherein any one of the plurality is incommensurable to at least one other of the plurality;    code for associating each transaction of the plurality of transactions to a respective number of the plurality of numbers;    code for engaging each transaction to the device at a particular simulation time that is based on the associated number of each transaction, wherein the particular simulation time is an integer multiple of the particular simulation time of a next of said each transaction; and    code for repeating the means for engaging for each transaction when the simulation time is an integer multiple of its associated number.    
   
   
       34 . The computer program product of  claim 33  wherein a portion of the plurality of transactions form a test case, and the code for engaging comprises: 
 code for looking up the test case in a table of test case entries and locating a list of transactions associated with the test case;    code for looking up each transaction of the list of transaction in a table of transactions and locating information associated with each transaction in the table; and    code for invoking a function for each transaction based on the information.    
   
   
       35 . The computer program product of  claim 34  further comprising: 
 code for invoking an emulator, via the function, to issue a command to the device based on the transaction.    
   
   
       36 . The computer program product of  claim 33  wherein the means for repeating comprises: 
 code for storing the particular simulation time in a memory;    code for calculating a subsequent particular simulation time by adding one of the plurality of incommensurable numbers to the particular simulation time; and    code for storing the subsequent particular simulation time after operation of the code for engaging.    
   
   
       37 . The computer program product of  claim 33  further comprising: 
 code for selecting the plurality of incommensurable numbers as non-identical prime numbers from the integers between n 1  and n 2 , wherein n 2  is greater than n 1 .