Jerome M. Kurtzberg

Timing driven placement using complete path delays

The Timing Drive Placement (TDP) system balances wirability and timing constraints so that the final released design meets timing criteria. This is achieved by dynamically evaluating the timing of critical paths during placement. TDP is significant because convergence to a timed wirable solution early in the physical design cycle is achieved, or else it becomes apparent that logic changes are required.

Feature analysis for symbol recognition by elastic matching

A technique has been developed for the recognition of unconstrained handwritten discrete symbols based on elastic matching against a set of prototypes generated by individual writers. The incorporation of feature analysis with elastic matching to eliminate unlikely prototypes is presented in this paper and is shown to greatly reduce the required processing time without any deterioration in recognition performance.

ABC: a better control for manufacturing

ABC is a generic methodology to improve the quality of manufacturing. It can optimize operation of a single process or an entire factory to meet or exceed product specifications. ABC is based on three nets which continually interact o model processes and to provide local process control and global product optimization. Significant process variables are identified, evaluated, and ranked according to their contributions to product quality. Process performance, which determines product quality, is characterized by a sensitive parameter, the Q-factor, which is used for local control and for global optimization. Real-time response maps capture process behavior and identify current status, improved operating points, and expected improvement in relation to design targets. ABC continually compensates for off-specification manufacturing steps by feedforward-andfeedback corrective actions which keep the product on target. ABC also evaluates and ranks the effects of non-numeric manufacturing variables, such as specific tools and vendors, on product quality. Total quality control can be achieved by optimizing all variables, both sensor-based and non-numeric, which control the product. Some of ABC’s capabilities are demonstrated in a multistep fabrication of a semiconductor capacitor in which the electrical properties of the product are optimized by controlling the individual chemical process steps. ABC’s capacity to minimize scrap and rework by compensating for out-of-control conditions is demonstrated in this example. A functional subset of ABC currently exists as a menu-driven tool, implemented in APW@ on VM/CMS for mainframe computers and in the C language for workstation platforms: RS/6000 running under AIX@ and PS/2@ under OS/2@. ABC is available, in the workstation version, as an IBM Program Offering under the name QuMAP-A Better Control, and is currently used in the semiconductor, pharmaceutical, chemical, and consumer goods industries.

On the Memory Conflict Problem in Multiprocessor Systems

This paper presents quadratic programming models of memory conflict in multiprocessor systems where main memory consists of a set of memory modules common to all processors. Two jobs (programs) are said to be in conflict, or subject to memory conflict, whenever at a given time portions of them must be executed in the same memory module by different processors. We are interested in minimizing the total conflict by the proper assignment of jobs to main memory. Two allocation models are considered: one in which the jobs-to-memory assignment is to be made independent of any particular processors-to-jobs schedule, that is, expected memory conflict is to be minimized over the space of all schedules; and the second in which a definite processor schedule is assumed to be available. For both models, algorithms are formulated for the assignment of jobs to memory.

A Balanced Pipelining Approach to Multiprocessing on an Instruction Stream Level

This paper presents an approach to achieve high central processing unit (CPU) availability with an increase in performance by multiprocessing on an instruction stream level, where instruction fetching/executing is done by closely coupled processing units (PUs). A treatment is given of the necessary control for coordination of the PUs. This processing interaction is accomplished by microcode shared by the units. Either PU can be interchanged in any processing function, and the total processing complex comprises a single CPU as far as the external world (i. e., the operating system and users programs) is concerned. The results of manual simulation on two sample problems are given along with a comparison of processing with a single PU and with another instruction stream multiprocessing scheme presented in [4].

ACE: A congestion estimator for wiring custom chips

Abstract Because wiring a chip is so time consuming, it is highly desirable to be able to evaluate a particular placement of macros on a chip in terms of its wirability, or choose among several candidate placements, prior to any actual wiring. A method is presented to do this. The expected wire congestion is derived and the critical areas exposed, thereby enabling improvement of the chip layout.

Computer design automation: what now and what next?

This special interest session of computer design automation explores the current problems that face us, what we can do and are accomplishing, and what appears to be our objectives and possibilities in the future.