Demand driven simulation: BACKSIM

ABSTRACT

A new digital simulation algorithm is presented based on the concept of demand driven simulation. Where traditional event driven simulation propagates signal values forward through a circuit in response to input pin events, demand driven simulation propagates requests for simulation values backwards both through the circuit and through time. In this manner, only those evaluations required to obtain “watched” signal values are performed. BACKSIM, the simulator based on this algorithm, has proven to be faster and more efficient than event driven simulation for every test case tried to date.

REFERENCES

• 1: Brglez, Franc, Phillip Pownall and Robert Hum, "Accelerated ATPG and Fault Grading Via Testability Analysis," Proceedings of the International Symposium on Circuits and Systems, 1985".
• 2: M Chiang , R Palkovic, LCC simulators speed development of synchronous hardware, Computer Design, v.25 n.5, p.87-92, March 1, 1986
• 3: Pfister, Gregory, "The IBM Yorktown Simulation Engine," Proceedings of the IEEE, pp. 850-860, June 1986.
• 4: "ZyCad LE-1001 Product Description," ZYCAD, 1982.

INDEX TERMS

Primary Classification:
  B. Hardware
  B.7 INTEGRATED CIRCUITS
      B.7.2 Design Aids
          Subjects: Simulation

Additional Classification:
  J. Computer Applications
  J.6 COMPUTER-AIDED ENGINEERING
      Subjects: Computer-aided design (CAD)

General Terms:
Algorithms, Design