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Show could be used, but has not been for two major reasons. First, CHAPTER 2 P AS! AND CURREKT EFFORTS AT CAD FOR SLA (PPL) It has been stated that the SLA, and therefore PPL, encourages the implementation of CAD tools for VLSI design. These tools use the SLA or PPL cell sets to implement both the logic and the composite layout of the circuit. Many efforts have been and are being made to exploi t the SLA (PPL) as an integrated circuit implementation saegy. These tool.s include file formats for representing SLA and ._ - ....... _ PPL programs, databases of SLA and PPL programs, graphical and r linguistic PPL (SLA) program editors, rudimentary compilers (although these have mainly been something which essentially edited existing designs) and PPL (SLA). logic simulators. Following are brief descriptions of past and current efforts in these areas. 2.1 SLA and PPL File Formats There have been several efforts to produce file formats to represent SLA and PPL programs. Caltech Intermediate Format· (ClF) extensi ve software would be needed to read CIF and transform it into the PPL program it represents. Second, CIF inherently contains no informati·on about logical function whereas SLA and PPL programs contain Ooth placement and functional information. Due to these two deficiencies.of CIF, several efforts were made to develop file formats |
