Parallel Very High Speed Integrated Circuits Vhsic Hardware Description Language Vhdl Simulation For Performance Modeling

As the complexity of microelectronic systems continuously increases, it becomes critical to develop effective tools that can cut the design time and improve the quality of design. DoD needs to develop new tools to be able to simulate large complex systems, and to fully maximize the rapid progress in high performance computing technology occurring today. The goal of this project was to develop and implement efficient paradigms for VHDL simulation on massively parallel processor machines so that we can achieve speed up of up to a hundred times compared to sequential simulation. Our research focus was on performance and behavioral level simulation. The performance model allows us to find the trade off between various hardware components and architectures. Behavioral simulations are used to prove the functional correctness of the system. The research issues involved in the project were: processor communications, synchronization, and event queue manipulation, deadlock handling, communication latency hiding, and granularity of computation. We have measured the performance of the proposed techniques on various platforms such as the IBM SP2 and SGI Origin 2000, and achieved speed ups of 31 times.

This research investigates the requirements needed to simulate VHDL electronic circuit descriptions by using an MC68020 based parallel engine. It analyzes the potential parallelism of the simulation of VHDL descriptions and presents a detailed design of the system hardware and software requirements. It presents timing models of the overall system for speedup, network operation, and synchronization. It concludes with a description of an N.2 simulation program which validates the operational characteristics of the design. (Thesis).

VHDL is a comprehensive language that allows a user to deal with design complexity. Design, and the data representing a design, are complex by the very nature of a modern digital system constructed from VLSI chips. VHDL is the first language to allow one to capture all the nuances of that complexity, and to effectively manage the data and the design process. As this book shows, VHDL is not by its nature a complex language. In 1980, the U. S. Government launched a very aggressive effort to advance the state-of-the-art in silicon technology. The objective was to significantly enhance operating performance and circuit density for Very Large Scale Integration (VLSI) silicon chips. The U. S. Government realized that in order for contractors to be able to work together to develop VLSI products, to document the resulting designs, to be able to reuse the designs in future products, and to efficiently upgrade existing designs, they needed a common communication medium for the design data. They wanted the design descriptions to be computer readable and executable. They also recognized that with the high densities envisioned for the U. S. Government's Very High Speed Integrated Circuit (VHSIC) chips and the large systems required in future procurements, a means of streamlining the design process and managing the large volumes of design data was required. Thus was born the concept of a standard hardware design and description language to solve all of these problems.

This book is intended to be a working reference for electronic hardware de signers who are interested in writing VHDL models. A handbook/cookbook approach is taken, with many complete examples used to illustrate the fea tures of the VHDL language and to provide insight into how particular classes of hardware devices can be modelled in VHDL. It is possible to use these models directly or to adapt them to similar problems with minimal effort. This book is not intended to be a complete reference manual for the VHDL language. It is possible to begin writing VHDL models with little background in VHDL by copying examples from the book and adapting them to particular problems. Some exposure to the VHDL language prior to using this book is recommended. The reader is assumed to have a solid hardware design background, preferably with some simulation experience. For the reader who is interested in getting a complete overview of the VHDL language, the following publications are recommended reading: • An Introduction to VHDL: Hardware Description and Design [LIP89] • IEEE Standard VHDL Language Reference Manual [IEEE87] • Chip-Level Behavioral Modelling [ARMS88] • Multi-Level Simulation of VLSI Systems [COEL87] Other references of interest are [USG88], [DOD88] and [CLSI87] Use of the Book If the reader is familiar with VHDL, the models described in chapters 3 through 7 can be applied directly to design problems.

The methodology described in this book is the result of many years of research experience in the field of synthesizable VHDL design targeting FPGA based platforms. VHDL was first conceived as a documentation language for ASIC designs. Afterwards, the language was used for the behavioral simulation of ASICs, and also as a design input for synthesis tools. VHDL is a rich language, but just a small subset of it can be used to write synthesizable code, from which a physical circuit can be obtained. Usually VHDL books describe both, synthesis and simulation aspects of the language, but in this book the reader is conducted just through the features acceptable by synthesis tools. The book introduces the subjects in a gradual and concise way, providing just enough information for the reader to develop their synthesizable digital systems in VHDL. The examples in the book were planned targeting an FPGA platform widely used around the world.

The success of VHDL since it has been balloted in 1987 as an IEEE standard may look incomprehensible to the large population of hardware designers, who had never heared of Hardware Description Languages before (for at least 90% of them), as well as to the few hundreds of specialists who had been working on these languages for a long time (25 years for some of them). Until 1988, only a very small subset of designers, in a few large companies, were used to describe their designs using a proprietary HDL, or sometimes a HDL inherited from a University when some software environment happened to be developped around it, allowing usability by third parties. A number of benefits were definitely recognized to this practice, such as functional verification of a specification through simulation, first performance evaluation of a tentative design, and sometimes automatic microprogram generation or even automatic high level synthesis. As there was apparently no market for HDL's, the ECAD vendors did not care about them, start-up companies were seldom able to survive in this area, and large users of proprietary tools were spending more and more people and money just to maintain their internal system.

Complete with coverage of the latest VHDL93 standard, this edition offers engineers a thorough guide to the use of VHDL hardware description language in the analysis, simulation, and modeling of complicated microelectronic circuits. Extensive worked problems and examples listed in Verilog as well as VHDL set this edition apart from other VHDL texts.