skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Assigning functional meaning to digital circuits

Technical Report ·
DOI:https://doi.org/10.2172/569121· OSTI ID:569121
;  [1]
  1. Argonne National Lab., IL (United States). Decision and Information Sciences Div.

During computer-aided design, the problem of how to determine the logical function of a digital circuit arises in many contexts. For example, assigning functional meaning to a circuit is a fundamental operation in both reverse engineering and implementation validation. This report describes such a determination by discussing how a higher-level functional representation is constructed from a detailed circuit description (i.e., a gate-level netlist, which is a list of logic gates and their interconnections). The approach used involves transforming parts of the netlist into a functional representation and then manipulating this representation. Two types of functional representations are described: (1) a mathematical representation based on the logical operators ``exor`` and ``and`` and (2) a directed acyclic graph representation based on binary decision trees. Each representation provides a canonical form of the logical function being implemented (i.e., a form that is independent of implementation details). Such forms, however, have a well-known problem associated with the ordering of inputs: for each order, a unique form exists. A solution to this problem is given for both representations. Experimental results that demonstrate the use of these representations in the process of assigning functional meaning to a circuit are provided. The report also identifies and discusses issues critical to the performance required of this fundamental operation.

Research Organization:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Organization:
Department of Defense, Washington, DC (United States)
DOE Contract Number:
W-31109-ENG-38
OSTI ID:
569121
Report Number(s):
ANL/DIS/TM-43; ON: DE98003113; TRN: AHC29805%%146
Resource Relation:
Other Information: PBD: Jul 1997
Country of Publication:
United States
Language:
English