Showing papers on "Routing (electronic design automation) published in 1968"

Optimum Curvature Principle In Highway Routing

Abstract: The problem of locating a highway between two given points is considered, so as to optimize a given criterion of merit. The calculus of variations is used to derive the Optimum Curvature Principle: the curvature of an optimum route at each point is equal to the percentage rate-of-change of the criterion function perpendicular to the route. The OCP is explained and described geometrically, illustrated by example, and compared to existing techniques. Practical aspects of its application are discussed, and areas for future research are indicated. Suggested areas of application include vertical alinement, horizontal alinement, minimize right-of-way cost, or cut-and-fill, or construction-plus-user cost, or cost/benefit ratio, or whatever criterion is selected.

Method and apparatus for routing data among processing elements of an array computer

Abstract: An interconnection scheme for routing data word information among the processing elements of an array computer is described wherein the word length is larger than, equal to, or smaller than the number of processing elements in the array. When the word length is equal to the number of processing elements, each processing element first transmits all but one of the bits of the word stored in its routing register to the corresponding bit positions of the routing register of the correspondingly numbered processing elements, one bit per processing element. Next the contents of the routing registers of all the processing elements are shifted by the routing amount. In the last step, the first step is repeated. In situations in which the word length is smaller than the number of processing elements hardware is added to some of the processing elements or the processing elements may be grouped into a plurality of subarrays. If the word length is larger than the number of processing elements the bits are grouped so that the number of groups is equal to the number of processing elements.

Stochastic optimal routing

Abstract: In this paper, we wish to introduce the idea of stochastic effects in optimal routing problems. This can be done by committing mistakes while making decisions. We will illustrate this idea by a classical puzzle: “The Wine Pouring Problem”.

Graphic display techniques in the automated interconnection process

Abstract: At present, it is necessary to negotiate a manual completion phase in wiring multi-layer interconnection boards used in aerospace computers. This phase occurs after automatic placement of logic modules and routing of the greater majority of the requisite wiring. The GAPE (Graphic Aids to Packaging Engineering) System utilizes an IBM 2250 to minimize not only time-consuming and error-prone functions in the wiring completion process but also the total amount of computer time required. Selection and routing of wires in an n-plane environment is controlled using a displayed set of functions which are activated by light pen and function keyboard. Routing is enhanced by the ability of the system to rapidly switch between planes and subsections of the planes. The system also permits re-routing of wires already placed either in their entirety or portions thereof. Description of the physical board to be wired is supplied at execution time for maximum system flexibility and minimum user intervention. System tape output interfaces with printed circuit generator functions.

Building block programs for the layout of printed circuit boards utilizing integrated circuit packs (DAPSYS V.2)

Abstract: This report describes the first set of proprietary design automation programs that will become available for licensing from C-E-I-R in 1968. The system (called DAPSY V. 2) is a group of building block programs that automate the layout and design of printed circuit boards using integrated circuit (IC) packs. The programs perform three basic functions: the logic is partitioned into IC packs, the packs are placed on the board, and the inter-connections are routed.