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Show 6 hardware, a secondary purpose is to show that PPL is indeed amenable to CAD tool development. While the SLA and PPL are b"oth superficially and' substantially similar, there are 'some subtle but essential differences which render: PPL more amenable to both integrated circuit design and CAD. These similarities and differences will be discussed in chapter 4. For a detailed treatment of the different SLA implementations he reader is referred to [73, 72]. In the discussions of implementation, it is assumed that the reader will at least be familiar with general PLA structure and the basic concepts of the SLA. 1.3 Research!!:. vtStCircuit Design Given an integrated· circuit implementation technique -(such as PPL.) , efforts can now be made to elevate the level of abstraction from graphics design of composites and electrical schematics. This elevation of the level of abstraction from rectangles, transistors and logic gates constitutes a major hurdle in the development of a true integrated systems design methodology. The rendering invisible of the transistor and graphical level details greatly reduces the complexity in current integrated circuit designs. It has already been shown in the SLA studies l 72 J that abstraction to the logical level from the transistor and graphics level reduces the complexity of circuit design by at least an order of ll!lagntude. Wi th only conventional graphical computer aids, deSign times for integrated circuits implemented using the SL! (or PPL) can |
