The following are excerpts from a conversation between Anna Walker (Director of Development for the School of Electrical and Computer Engineering) and Professor Emeritus John Peatman. John joined the School faculty in 1964 and served with distinction until he retired in 2014. He developed the digital design program in the School and taught his immensely popular senior elective that evolved from Digital Systems Design to Embedded Systems Design over the course of his career. He was named Outstanding Professor both within ECE and campus wide. He wrote seven textbooks, widely utilized both at other universities and in professional practice. By virtue of his truly outstanding pedagogical scholarship, John contributed greatly to the reputation of our School as a center of excellence in electrical engineering education.

Anna: Thank you for taking the time to talk with me. Your career at Georgia Tech touched the lives of many, most of whom will be recipients of the forthcoming School newsletter in which excerpts from our conversation will appear. I’m certain that all the recipients will enjoy hearing from you.            

John: Thanks Anna, I am pleased to visit with you. After agreeing, I spent some time thinking about what I would say. I discarded the notion of defining a career timeline in favor of just talking about what I view as some highlights of my career.

Anna: Perfect! Perhaps we can begin by talking about the beginning of that career, how you came to Georgia Tech?

John: I was nearing completion of my Ph.D. at Case Western University and was looking to continue the academic career that had begun with two years of teaching at Missouri School of Mines in Rolla, Missouri. A fellow doctoral student at Case, Lou Holliman, had been on the mechanical engineering faculty at Georgia Tech before coming to Case to complete a Ph.D., and he extolled the virtues of Georgia Tech. Both my wife Marilyn and I were attracted to this urban location. I, of course, knew of Georgia Tech, that it had a good academic reputation and an established graduate program. So I applied to Georgia Tech and was invited to interview.

I met Dr. Ben Dasher, School Director, in his spacious office in the brand-new Van Leer Electrical Engineering Building. He was an engaging gentleman, and we proceeded to have an interesting conversation. At some point the conversation was interrupted by a telephone call. Ben answered and held forth with a strong southern accent. When he hung up, I asked him what the different accent was about. He laughed and explained that having grown up in South Georgia, that was his natural accent. When he went to MIT to pursue his doctorate, he found that his southern accent was a professional liability. By mimicking others, he developed the accent he had been using with me. I was impressed by his candor. He seemed like a boss under whom I could flourish. I liked his vision for the School, which included the need to develop programs in digital systems engineering, and I liked the environment. So, when I was offered a position as assistant professor, I accepted and joined the faculty in fall quarter 1964. It was a fortuitous choice. 

Anna: I understand that your career progressed from the days of gates and flip-flops to the early days of microprocessors, and on to microcontrollers (i.e., one-chip computers).  Describe the succession.

John: My first lab used RTL logic gates and flip-flops. My second lab used what became the dominant family of logic parts, TTL logic which included not only gates and flip-flops but also what was then called MSI (medium-scale-integration) logic, e.g., counters, data selectors and decoders. Motorola’s first microprocessor, the 6800, led to a major change in our activity, followed by their 6809 microprocessor. Hewlett-Packard’s gift of a sophisticated development system led to our first use of a microcontroller, Motorola’s 6801. Motorola’s 68HC11 microcontroller led to new vistas for us as we moved on from the use of an expensive development system to a student-designed logic analyzer board used to track and control the execution of program instructions. Subsequent to this, as Microchip Technology gained a foothold in the very low-cost microcontroller business, we switched to their early PIC microcontrollers together with their hand-held PIC debugging pods. As Microchip Technology developed flash program memory, we migrated to the PIC18F452 microcontroller. Not only could we download a program into the chip and run it, but we could include student-developed, sophisticated debugging capability within the chip. It would accept commands to run to a breakpoint and then single step the program while displaying internal registers. 

Anna: Your senior elective was always popular. Any comment?

John: Early on I realized the power of my creating a new lab design project every week, to challenge my students with real-world activity. Not only did they like meeting the challenge, but they also appreciated the absence of “word” from the same project being repeated from a previous quarter. At the same time, this also drove me to augment the lab with new devices around which to build projects.

As we began to work with microprocessors, the success of my lab depended heavily upon having lab teaching assistants who had previously taken my course. Over all the years of my teaching, I am grateful that our department supported the extra budget for my undergraduate TAs. It made all the difference. It was a treat for me to approach my best students and ask if they would like to serve as a TA for my lab. And what an outstanding group they have been over many years!

Anna: Building a new lab is always a challenge for a new professor. How did you get started?

John: I was fortunate in 1966 to secure an NSF grant that permitted us to build what we called a digital synthesizer. It had a panel of binary switches and thumbwheel switches for input and binary lights and Nixie tube decimal lights and a stepper motor for output. Digital logic components were connected together and to the input/output devices via a plug board receiver. Thirty-five custom built plugboards allowed each student to use the plugboard assigned to him/her (not many “hers” in those early days!) and implement his/her own design for a specified project with plugwires inserted into the plugboard with its lettered and color-coded pattern. It was quite sophisticated for those early years of digital design.

Anna: What was distinctive about Georgia Tech to you as a new professor in your early years?

John: When I first came to Georgia Tech, my assignments included developing and teaching undergraduate and graduate courses in Digital Systems Design. As my career evolved, it became clear that I had less interest in graduate research but was passionate about undergraduate teaching and laboratory development for my digital design senior elective.  The resulting migration was acceptable as a career trajectory, in contrast to what I would have found at many other schools. Furthermore, my course was driven by what we were doing in the laboratory. Each day I’d show up in class with a fresh set of handout notes for the students. Pretty soon I wanted to turn the notes into a formal textbook, but between the heavy academic year teaching load, the necessity to secure summer jobs, and participation in raising my young family, it was difficult to find time to dedicate to a book. Demetrius Paris, who succeeded Ben Dasher as school director, made a huge difference in my life by offering to support me on the summer budget in 1970 if I would remain in Atlanta, devoting my time exclusively to the completion of my first book before the fall quarter began.

I will be forever grateful to Demetrius for his unflagging support. Even in years of tight budgets, Demetrius made a huge difference. He was aware that I was consuming more than my fair share of his copying budget but he never raised the issue, knowing that the materials consumed drove my ever-evolving lab and course development activities and thereby, my textbook writing.

After completion of that summer manuscript, I consulted with my office neighbor Kendall Su, a very successful textbook author, on how to get the book published. He wisely advised that I submit the manuscript to all six or so major engineering textbook publishers. He pointed out that an editor could have an unspoken reason to discourage an author, perhaps seeing the book as a possible competitor to a forthcoming textbook of their own. McGraw-Hill came back to me with a contract. In fact, the manuscript was written by me in pencil and, after considerable editing by my wife Marilyn, was typed on an IBM Executive typewriter with its proportional type font. She produced amazingly clean pages that looked very different from what a book editor was used to receiving — heavily marked up pages and a normal typewriter’s monospaced type font. McGraw-Hill bypassed the galley proof stage and skipped directly to page proofs resulting in a 1972 early release of the book.

Anna: What else was going on in your early career?

John: I had been invited to the 1968 Freshman Camp by an enterprising rising senior, EE student Jim Carreker. He included me with his cabin-mate freshmen to meet in a Van Leer classroom the night before leaving for Rock Eagle. We sat in a circle and Jim asked each of us to give our name, hometown, and something about ourselves. Then Jim repeated this information flawlessly and followed up with each freshman doing the same, bonding them towards lasting friendships. Thank God, Jim allowed me to skip the memorization process! 

Subsequently, Jim came to me and together with Neal Williams (who would go on to be valedictorian of his class) suggested that we initiate an EE Senior Seminar as a one-hour elective open to juniors and seniors for the 1969 spring semester. After securing authorization for the elective, Jim, Neal, Ray Miller, and Ray Eberle proceeded to invite 10 distinguished people to come and talk to our seniors about subjects of value upon completion of a degree from Georgia Tech. They invited the head of Stanford’s EE school, the admissions director from Harvard Business School, the lead designer of CDC’s supercomputer, the father of inertial guidance from MIT, an expert on personal financial planning, and five others. It was a revelation to me that these seniors could attract eminent leaders without the availability of travel expenses or even an honorarium. At that moment I realized that these students had unleashed a powerful opportunity that I would continue every spring quarter until Georgia Tech switched from quarters to semesters in 1999.

Anna: Give me an overview of the book writing part of your career.

John: The technology of digital systems was continually changing and advancing, necessitating upgrading of materials for my course and resulting, over time, in the publication of six additional textbooks. My second book Microcomputer-Based Design was published by McGraw-Hill in 1977. It was the groundbreaking book after microprocessors first came on the scene. Sales were evenly split between students and practicing engineers, so I ended up working with both the College Division of McGraw-Hill and their Professional and Reference Book Division on the promotion of the book. It was my bestselling book and funded our children’s college careers. McGraw-Hill published my third book in 1980 and the fourth in 1988. My fifth and sixth books were published by Prentice-Hall in 1998 and 2003.                           

My seventh book Coin-Cell-Powered Embedded Design provided a bit of reminiscence.  Because the cost of technical books was ranging around $125-150, I decided to self-publish the book in 2008, utilizing funds accrued from royalties on my previous books. I contacted the person at the company in Chennai, India, who had done the artwork for my previous book. She agreed to do the same plus prepare the page proofs and cover art. I engaged Lulu.com, a print-on-demand publisher to print the book from the resulting pdf pages. I set the price of the book at $16.50, the price McGraw-Hill charged for my first 1972 book.  In addition to providing this printed copy, Lulu agreed to provide the pdf pages on their website. Georgia Tech students could use their library privileges to print a free copy. I was very pleased with the outcome.

Anna: I understand that because you organized your sixth book around a PC board that you had designed, you ended up with some fascinating former student interactions. 

John: Yes. I had designed what I called a QwikFlash board for my sixth book entitled Embedded Design with the PIC18F452 Microcontroller. The intent was to take what was at the time the top of the line microcontroller of a leading microcontroller company, Microchip Technology, and build a board that could provide a professor with the makings of a microcomputer lab with only the addition of a personal computer. When I approached my editor at Prentice Hall, he was excited about publishing it, not realizing the implication of the QwikFlash board. As we proceeded with the publishing of the book, we talked about the appendix with a parts list for the board and the directions for populating it with these parts. I talked about my plan to include a bare board in a CD sleeve mounted inside the back cover of the book. He balked. He said there was no way he could do that. “Find some other way to deal with that problem, John!” He felt that it was counterproductive to have a potential buyer of the book feel that the price included some unknown amount to pay for the board. I came up with two solutions that satisfied him. By this time, former student Jim Carreker had established an endowment for a chaired professorship in our department. But it had gone unfilled for several years, so I called Jim and asked if he would be amenable to using some of the accrued interest to pay for the boards for the first printing of the book.  He agreed and to allay the worries of my editor, a note was included inside the back cover along with the board saying, “The QwikFlash board in this first printing has been provided to you gratis by Jim Carreker, former student and continuing friend.”

The second solution dealt with two issues. How to support the book for a professor who didn’t want to be building boards and how to support the book after that first printing. I talked to two former students and ongoing friends, Bill Kaduck and Dave Cornish, who had created a local company, Microdesigns, some years earlier. I asked them if they would build the board and sell it at cost. To this day they do so from their website www.microdesignsinc.com. It has made all the difference to the life of the book!

Anna: What have been your other interactions with industry?

John: I spent a significant fraction of my early career working directly for Hewlett-Packard. I spent five summers as a digital designer in Colorado Springs, Loveland, Palo Alto, and a year in Scotland. I have always been very grateful to Hewlett-Packard for all of their support.                  

I served as a director from 1977 to 2014 of a local company, Intelligent Systems Corp., formed by one of our graduates, Charlie Muench. Leland Strange, a Georgia Tech graduate, carried on over the years as CEO. I used some of my director’s fee to buy components for experiments to enhance my lab and subsequently to defray the cost of designing and fabricating “evaluation boards” and “target system boards” with which new generations of microcontrollers could interact with an increasingly sophisticated selection of I/O devices like thumbwheel switches, digital incremental encoders, temperature sensors, stepper motors, magnetic card readers, alphanumeric displays, and even a DigiTalker speaking chip. Over the years and with the help of former student Rick Farmer, we produced new generations of boards to take advantage of advancing developments in microcontrollers and new sophistication in I/O devices.                                       

Anna: Didn’t you gain industry support for some of your lab activities over the years?

John: In 1976 Bryant Wilder, a Motorola engineer and former student, had Motorola give us what they called an EXORciser which led to our getting into the microprocessor laboratory business and the incorporation of microprocessor design into my subsequent books. The EXORciser included a Motorola 6800 microprocessor with associated memory and input/output circuitry. We built a target system board with switches for input and LEDs, a stepper motor, and a seven-segment display for output. By employing a complicated process utilizing the campus computer to write assembly language code for a control design, and the help of Jim Stratigos, a graduate student at the time, we could download the code to the EXORciser and run it to effect sensing and control of the target board elements. The process was tedious and totally absent of debug capability but did afford students the opportunity to do rudimentary microprocessor design.    

A major step forward occurred in 1982 when HP gave us their new six station HP64000 Universal Development System that enabled students to develop the program code on the HP64000 and run it on the target board. Over the next several years we built increasingly sophisticated target boards. Each station in the laboratory was equipped with a system for program development and execution with complete debug capability.

Anna: Talk about the projects that led to commercial products.

John: In 1989 Larry Madar and Joe Bazzell worked with me on the design of a two-board evaluation board set. This two-board set provided considerable capability to help a professor build a lab around a microcontroller. Motorola sold it to schools pretty much at cost.

I built my last book around a Qwik&Low board that we designed to form a complete instructional lab. The board includes two chips, a microcontroller, and an alphanumeric LCD controller together with a few other I/O devices. It uses a coin cell for power, and connections to a DC microammeter for monitoring average current—a big deal for such applications. Microchip Technology, via the support of former student and friend, Rawin Rojvanit, sold the board to schools to support a lab for low power applications using this microcontroller.

Anna: What led to your career decision to stay focused on low-cost microcontrollers even as much of the world moved on to ARM chips and their full-bodied competitors?

John: I aimed at the many applications of these low-cost chips in industry. It soon became apparent that an electrical engineering graduate could go to work for almost any manufacturing company and sooner or later find the chance to build “smarts” into their products with an added cost defined more by the cost of development than by that of the parts.

Anna: What are other developments in which you take exceptional pride?

John: We began our microprocessor/microcontroller work, learning to do simple things.  For small applications, programming in assembly language (the native language of the chip) made sense, and so this was the language of choice for us. As applications grew in size, the resulting “spaghetti code” with disorganized program flow produced unreliable program execution because of the difficulty of debugging program code. In the early 1980s, Skip Addison took advantage of a feature of the HP64000 development system’s assembler to add structured constructs to the assembly language. Thus, the IF-THEN-ELSE construct executes a test and controls the resulting flow of a program. In similar manner the DO-WHILE construct repeats a sequence of instructions over and over again until a test condition is met. Following this introduction, program coding in my lab was transformed. Subsequently as we moved beyond the HP64000 development system, Jessica Meremonte developed a structured assembly preprocessor for an assembler that would insert the assembly language translation of these same structured constructs into an assembly language program.

We eventually switched to the use of the C programming language because the “self-documenting” feature of the resulting programs was becoming a recurrent demand from industry. In fact, a lot of what makes a C program self-documenting eliminated the “spaghetti code” control flow that we had long since eliminated with our structured assembly programming.

Anna: You clearly had a wonderful relationship with your students. In my encounters with alumni, your name always comes up as one of their favorite professors.     

John: Tech students are the best. Being a top-notch but relatively low-cost school attracting the best students has been wonderful. Furthermore, any honest professor will tell you that one of the attractions of the profession is the chance to work with students who are smarter than you. The chance to pursue new tool development and equipment development with superstar TAs created most of the highlights of my career. Without going on, let me just point out that I dedicated my last book: “To six former students who changed the direction of my professional life: Jim Carreker and Neal Williams, 1968-1969, Joe Bazzell and Larry Madar, 1989-1990, and Rawin Rojvanit and Chris Twigg, 2001-2002.”

On the first day of class I would hand out a sheet asking for information on the students, including a request that they provide the name or nickname that they preferred to be called by. I would use that name in calling roll as a means of connecting with students.  And I insisted that they call me John.                                             

Anna: Thank you very much for a most interesting and enjoyable conversation. Is there anything you wish to add?

John: Yes, I almost forgot a very important point. I prepared all my class and lab handouts myself directly with my typewriter, in the early days, and on my personal computer, subsequently. In contrast, all my books, from first to last, were written in pencil on pads of paper. Then my wife Marilyn would take my page-long sentences and grammatical slips and make sense of it all. She even learned the jargon along the way. Without her, I never would have had a book writing side to my career.

Anna: Thank you so much for remembering to include that.