The Designer's Guide to VHDL:

Though I have some background in VHDL, the amount of information you can gain from this book is exceptional. There are plenty of examples and the structure of the flow of information is well engineered However, the fact that it touches many topic in much detail can turn into a disadvantage for beginners.

I have a couple of other VHDL books but I can't find them, for some reason I have two of copies of 'The Designer's Guide to VHDL'. When reading this book it is apparent that Ashenden thoroughly understands VHDL - excellent examples and I really like the VHDL-93 viewpoint with the VHDL-87 differences sprinkled throughout. If you really want to learn to design first-class test benches, you need this book. It has text IO coverage and in depth information on components, configurations and packages.

Before Ashenden there was Douglas Perry. Perry's book on VHDL (Second Edition) was pretty well written and handled HDL for synthesis quite well. After Perry, I was introduced to Ashenden's "The Designer's Guide to VHDL". This is by far the must have VHDL reference manual. Ask yourself, what is important in a good reference manual...the answer is well organized concepts, good examples and a thorough index! This book has it all. I have other VHDL books that just get dusty on my shelf, not this one! If I'm not using it, someone else usually wants to borrow it. If your looking for a great VHDL book...pick this one up or borrow it.

Ashenden covers many of the finer points of the VHDL language including differences between '87 and '93 implementations. I have used suggestions from his book with Cadence, Synopsys, Altera, Xilinx, and Model Tech tools for several years without any problems(all source code for the book is available at his web site). In addition, this is one of the few books to handle text and file I/O adequately, a real necessity for test bench design. Along with Kevin Skahill's and Douglas Smith's(dual Verilog/VHDL coverage, real handy) books it's definitely in the top 3.

The Designer's Guide to Vhdl, by Peter J. Ashenden is a very good book for all level of Vhdl programming. Tutors the basic to advance level programming in Vhdl. Extensively covers the Behavior Modeling by many examples and case studies. If you are looking something on synthesis, this book does not cover whole lot on it, but it's worth buying for reference since the price of the book is not that expensive compare to others.