RTL Hardware Design Using VHDL: Coding for Efficiency, Portability, and Scalability

PREFACE

With the maturity and availability of hardware description language (HDL) and synthesis software, using them to design custom digital hardware has become a mainstream practice. Because of the resemblance of an HDL code to a traditional program (such as a C program), some users believe incorrectly that designing hardware in HDL involves simply writing syntactically correct software code, and assume that the synthesis software can automatically derive the physical hardware. Unfortunately, synthesis software can only perform transformation and local optimization, and cannot convert a poor description into an efficient implementation. Without an understanding of the hardware architecture, the HDL code frequently leads to unnecessarily complex hardware, or may not even be synthesizable.

This book provides in-depth coverage on the systematical development and synthesis of efficient, portable and scalable register-transfer-level (RT-level) digital circuits using the VHDL hardware description language. RT-level design uses intermediate-sized components, such as adders, comparators, multiplexers and registers, to construct a digital system. It is the level that is most suitable and effective for today's synthesis software.

RT-level design and VHDL are two somewhat independent subjects. VHDL code is simply one of the methods to describe a hardware design. The same design can also be described by a schematic or code in other HDLs. VHDL and synthesis software will not lead automatically ...