Help me write my FPGA book

Help me write my FPGA book
Good grief! Please tell me that it's not August already, because I'm not even ready for July to start yet. Currently I'm up to my ears writing a book on FPGAs — specifically on the types of components that are now available and on design tools and flows (especially those like C-based flows that have only recently appeared on the scene). In fact this book is the focus of this column, because I'm soliciting your help with regard to:

• Any special, non-mainstream (possibly in-house) design tools you're aware of (if you have an internally developed tool, this is your chance to get it a good mention).
• Any interesting and/or unusual design flows and methodologies you're aware of.
• Any interesting and/or unusual applications you've created FPGAs to serve.
• Any thoughts about other topics you'd like to see covered in this type of book.

"But first, a word from our sponsors ...."

As it happens, I've long been interested in creating a book on FPGAs, so I was delighted when my publisher — Carol Lewis at Elsevier Science (which I'm informed is the largest English language publisher in the world) — presented me with the opportunity to do so.

There was one slight "fly-in-the-soup," however, in that I've spent much of the last ten years of my life slaving away at my real job during the days, and then whiling away my evenings and weekends penning books. At some point it struck me that it would be nice to "get a life" and spend some time hanging out with my family and friends. So I started asking around, and was delighted when the folks at Mentor Graphics and Xilinx offered to sponsor the creation of this tome, thereby allowing me to work on it during the days and to keep my evenings and weekends free for my own devices.

Even better, being an engineer by trade, I hate picking up a book that purports to be technical in nature, but which somehow manages to mutate into a marketing diatribe while I'm not looking. Thus, I was delighted when both sponsors made it clear that this book should not be Mentor-centric or Xilinx-centric, but should instead present any and all information I deemed to be useful without fear or favor.

What IS going to be in the book?

Life was relatively uncomplicated in the early days — circa the mid 1980s — when FPGAs had only recently leapt onto the stage. The first devices contained only a few thousand simple logic gates (or the equivalent thereof), and the flows used to design these components — predominantly based on the use of schematic capture — were easy to understand and use. By comparison, today's FPGAs are incredibly complex and there are more design tools, flows, and techniques than you can swing a stick at.

So my book commences by introducing fundamental concepts and the various flavors of FPGA architectures and devices that are available. It will then explore the myriad design tools and flows that may be employed depending on what the designer is hoping to achieve. Furthermore, in addition to looking "inside the FPGA," this book will also consider the implications associated with integrating the device into the rest of the system in the form of a circuit board, including discussions on the gigabit interfaces that have only recently become available.

What's NOT going to be in the book?

This tome is not going to focus on particular FPGA vendors or specific FPGA devices, because new features and chip types appear so rapidly that anything I write would be out of date before the book hit the streets (sometimes before I manage to complete the sentence).

Similarly, as far as possible (and insofar as it makes sense to do so) this book will not make mention of individual EDA vendors or reference their tools by name, because these vendors are constantly acquiring each other, changing the names of, or otherwise transmogrifying, their companies, and/or varying the names of their design and analysis tools. Similarly, things evolve so quickly in this industry that there is little point in saying "Tool A has this feature but Tool B doesn't," because in just a few months' time Tool B will probably have been enhanced, while Tool A may well have been put out to pasture.

For all of these reasons, this book will introduce different flavors of FPGA devices and a variety of design tool concepts (including desirable capabilities) and flows, but it will leave it up to the reader to research which FPGA vendors support specific architectural constructs and which EDA vendors and tools support specific features (useful web addresses will be presented in the chapter entitled Who Are All the Players?).

Who is this book for?
This is something of a curious, atypical book for the technical genre (and as the author, I should know). I say this because this tome is intended to be of interest to an unusually broad and diverse readership, which includes:

• Small FPGA design consultants
• Hardware and software design engineers in larger system houses
• ASIC designers who are migrating into FPGAs
• DSP designers who are starting to use FPGAs
• Students in colleges and universities
• Sales, marketing, and other guys and gals working for EDA and FPGA companies
• Analysts and magazine editors

The primary audience comprises fully-fledged engineers who are currently designing with FPGAs or who are planning to do so in the not-so-distant future. Thus, Section 2: Creating FPGA-based Designs will introduce a wide range of different design flows, tools, and concepts with lots of juicy technical details that only an engineer could love. By comparison, other areas of the book — such as Section 1: Fundamental Concepts — will cover a variety of topics at a relatively low technical level.

The main reason for this dichotomy is that there is currently a tremendous amount of interest in FPGAs, especially from people who have never used or considered them before. The first FPGA devices were relatively limited in the number of equivalent logic gates they supported and the performance they offered, so any "serious" (large, complex, high-performance) designs were automatically implemented as application specific integrated circuits (ASICs) or application-specific standard parts (ASSPs). Designing and building ASICs and ASSPs is an extremely time-consuming and expensive hobby, however, with the added disadvantage that the final design is "frozen in silicon" and cannot be easily modified without creating a new version of the device.

By comparison, the cost of an FPGA design is much lower than that of an ASIC or ASSP. At the same time, implementing design changes is much easier in FPGAs and the time-to-market for such designs is much faster. Of particular interest is the fact that new FPGA architectures containing millions of equivalent logic gates, embedded processors, and ultra-high-speed interfaces have recently become available. These devices allow FPGAs to be used for applications that would, until now, have been the purview only of ASICs and ASSPs.

With regard to those FPGA devices featuring embedded processors, such designs require the collaboration of hardware and embedded software engineers. In many cases, the software engineers may not be particularly familiar with some of the nitty-gritty design considerations associated with the hardware aspects of these devices. Thus, in addition to hardware design engineers, this book is also intended to be of interest to those members of the software fraternity who are tasked with creating embedded applications for these devices.

Further intended audiences are electronics engineering students in colleges and universities; sales, marketing, and other guys and gals working for EDA and FPGA companies; and analysts and magazine editors. Many of these readers will appreciate the lower technical level of the introductory material found in Section 1 and also in certain of the "101-style" appendices.

Last but not least, I tend to write the sort of book that I myself would care to read. (At this moment in time, I would particularly like to read this book — because then I would have some clue as to what I was going to write, if you see what I mean.) Truth to tell, I rarely read technical books myself anymore, because they usually bore my socks off. For this reason, in my own works I prefer to mix complex topics with underlying fundamental concepts ("where did this come from" and "why do we do it this way") along with interesting nuggets of trivia. This has the added advantage that when my mind starts to wander in my autumn years, I will be able to amaze and entertain myself by re-reading my own works (it's always nice to have something to look forward to).

And so there you have it. I'm presently deep in the throws of writing, which means — I'm reliably informed — that I've assumed my "Creative Genius" persona (a cross between an eccentric professor mumbling to himself and making notes on any available surface, and a village idiot with clothing and hair in disarray). So please start sending me emails with your input for this book (which has to be in the publisher's hands by the end of November), and until next time, have a good one!

Clive (Max) Maxfield is president of Techbites Interactive, a marketing consultancy firm specializing in high-tech. Author of Bebop to the Boolean Boogie (An Unconventional Guide to Electronics) and co-author of EDA: Where Electronics Begins, Max was once referred to as a "semiconductor design expert" by someone famous who wasn't prompted, coerced, or remunerated in any way.