I suspect I am one of the older—possibly the oldest—denizens here. When I started with electronics the transistor was barely out of the laboratory stage of its existence. Electron tubes in the radio and monochrome TV kept the house nice and warm in the winter time, and sparked (!) my curiosity about all things electronic. During my high school years (1959-1963) I built tube-powered hi-fi amps, culminating in the design of a power amp that used the newly-developed 8417 beam power tetrode, and could produce 100 watts RMS output at about one percent THD. I arguably had the loudest stereo of anyone in school at the time.
While in high school, I developed some interest in computing after listening to a talk by someone from Sperry-Univac. At the time, I had an uncle who ran a juke box and pinball machine business, from which all sorts of used parts, mostly relays and such, came my way, especially Automatic Electric rotary stepping relays.
My senior high school science project was a sort of von Neumann architecture "computer" built from a bunch of those rotary stepping relays (they acted as memory), conventional relays (they were the glue logic—that term barely existed back then), a couple of telephone dials and push buttons to accept input, blinking lights (gotta have those!) and a binary-decimal decoder, also built from a pile of relays, that drove a crude 7-segment display made from automobile dashboard lights. It took me several months to build this contraption and several more months to get it to work right. When it came time to take it to school we had to rent a truck—it was too big to fit into the trunk of my stepfather's 1960 Chevy.
I won first place in the school science fair, and third place in the state science fair.
After finishing high school, I enlisted in the U.S. Navy, where I encountered my first "real" computer, a tube-powered monstrosity at the Great Lakes Training Center Electronics School. This was a more-or-less general purpose machine, controlled by a Friden Flexowriter, and capable of performing a blistering 4000 calculations per second—about the speed of a cheap pocket calculator. It was installed in one of the few air conditioned rooms in the school. I don't recall how many tubes were in it but I do recall it had its own three-phase power source.
Aboard ship, I was part of the electronics gang responsible for maintaining the various radio transmitters and receivers, as well as radar and other assorted gadgets. During this period, the Navy started to acquire hybrid equipment, in which the lower-powered circuits were solid state and the rest tubes. I attended some special schools to learn how this stuff worked and how to repair it. It was clear to me even then that tubes were on their way out for anything other than high powered circuits.
As this ship was a World War II era destroyer, it had a main battery of six 5 inch guns in three turrets, which were capable of doing a frightful amount of damage (they also made the most unbelievable racket when fired). Controlling them was an analog ballistic computer, which received inputs from gyros, radar and other sources, and figured out how to aim the guns This system worked well enough that we could easily pick off targets over nine miles away, or knock out aircraft flying in the stratosphere. I think it was seeing this working example of processing power that led to my career with computers.
After leaving the Navy, I held a couple of electronics jobs and then, through some fortuitous circumstances, got a job working with a primitive computer system called the ZIP Mail Translator or ZMT. The ZMT was the U.S. Post Office's first foray into using digital technology to sort the mail. It interfaced to an electromechanical letter-sorting machine (which was almost as big as a small house), accepted a partial ZIP code and then routed the mail to one of 256 possible bins (hmmm...an 8 bit machine). Bin zero was the "error" bin, into which misdirected mail would go. During the debugging stages, the error bin frequently overflowed onto the floor.
I spent quite a bit of time programming ZMTs, as I had, for unfathomable reasons, developed an affinity for the crude machine code that told the thing what to do. Programming was, no surprise, done with a Tele-Type machine, which ultimately got the code written to a Ferro-Cube memory unit. The machine had 8K of memory—8 kilobits, that is.
After the close of the ZMT project, I got involved with traffic control equipment at another company, where my experience a decade earlier with my relay computer came in handy. While at that company, I concocted a bi-stable circuit that worked with two small relays and two diodes, acting as the electromechanical equivalent of a single input set/reset flip-flop. I was awarded (in 1975) a U.S. patent for the design. I also received another patent for the development of a traffic priority control circuit.
In the mid-1970s, another fortuitous circumstance landed me a job with a prominent supplier in the surface transportation industry. Among the many projects they had under development was an event recorder for use in locomotives, a device that paralleled the function of the flight data recorder found in commercial airliners. The original design was built around the Z80 MPU, but not too long after I joined the company, the 6502 had become available, and for much less money per unit. A new design built around the 6502 replaced the Z80 unit (which was three times as expensive to build and a royal pain to program) and that's where it got interesting.
The electronics engineers who were developing the recorder needed someone to write the software for it. One of them knew Z80 assembly language, but none knew the 6502 version. I looked at it and decided I could learn the language in short order. It wasn't as simple as it looked, but I persevered and soon mastered 6502 assembly language programming, using the reference assembler provided by MOS Technology. The event recorder was installed in all Amtrak locomotives and devices like it eventually became standard equipment on all locomotives in the USA and Canada, although later ones were not 6502 powered.
I stayed with this company for nearly 15 years, and in fact, wrote some software that ran on their IBM 360 mainframe, using FORTRAN and COBOL (ugh!). There was also a DEC PDP-11 there, on which was running UNIX (this was c. 1980). Needless to say, I spent plenty of time on that machine, as the UNIX environment was interactive, which was more than could be said about the IBM 360.
In 1983, a purchase was to play a role in my future career. I bought a Commodore 64 almost as a lark, just so I could say I had my very own home computer. BASIC was much too slow, so, knowing the 6502 assembly language, I started writing M/L routines to speed up BASIC programs. The following year, a life-long friend went into the automobile repair business and soon realized that using a computer would make it easier to run the business. The problem was an IBM PC was financially out of reach, and there weren't any good packages tailored to an auto repair business (some amateurish stuff had been written for the Apple ][, but was as bug-ridden as the beds in a skid row flophouse).
So I put together something for him that would run on a C-64 and that got him up and running. It was a mixture of BASIC and M/L, the latter mostly for sorting and searching. The following year, after the Commodore 128 had come out, I converted him to the C-128, and in the process, realized one could make some money doing this sort of stuff. That lead to the formation of my company
In 1988, I got a job developing software for a truck leasing company, which was right after I had built my first UNIX server (powered by SCO Unix 3.2). This was supposed to be something I'd do during my off-hours. However, as I started cranking out code and demonstrating it to the client, they started coming up with more and more features to include in the finished project. It quickly became apparent I would be trying to serve two masters by working on the truck leasing system while employed full time.
So I sized up my financial situation (which was okay at that time), took a deep breath, quit my job at the transportation supply company and joined the ranks of the self-employed. Although lean times have struck now and then, I haven't looked back and have managed to make some money and occasionally have some fun. I've had the satisfaction of designing and installing a number of large-scale UNIX and Linux powered systems (one with nearly 50 users), as well as the scratch-development of several vertical packages.
Things changed a bit early in 2007, when I developed a potentially deadly immune system malfunction
that has proved to be costly and difficult to treat. I jokingly refer to it as Pac-Man disease—for reasons that become obvious once the nature of the problem is understood—but it's no joke. For a time, I was too weak from the effects of rounds of chemo to work much, and between that and the medical costs that weren't covered by my insurance, I got financially upside down for a while. Things got even bleaker in early 2008, when my condition worsened and I skidded perilously close to the edge of the metaphoric cliff, only to be temporarily pulled back by surgery. Fortunately, a newly-released drug in August 2008
turned things around, allowing me to maintain a moderate work schedule while being treated. I've now been on this drug for three years and so far, so good. In all likelihood, I will continue to require it for the remainder of my life. And that leads up to how I ended up here at 6502.org.
In early 2009, I decided for health reasons to cut back on my work schedule and only take in projects that would not require months of planning and work to come to fruition—I wasn't sure that I could stay in it for the long haul. I also cut back on my server building business because the physical aspects of the work were becoming increasingly difficult to handle. With more time on my hands, I started looking for things to do that I could manage in my permanently weakened state. That's when I thought about trying my hand at designing and building a small computer. Naturally, with so many years of 6502 experience behind me, the choice of microprocessor wasn't hard. That's what got me started on my POC unit
My ultimate goal is to build a 65C816 powered system capable of running a pre-emptive multitasking operating system fashioned along the lines of UNIX. Once I have a working kernel, I can develop all the tools that I think might be useful. I don't have any particular plan for how I might use the thing. The fun is in the building and problem-solving. I'm hoping this sort of project will keep my mind active and (more-or-less) fully functional as I head into the so-called golden years.
By the way, computers aren't all I do. My other principal interest is large-scale model railroading. Shortly before Pac-Man attacked, I scratch-designed and started building a one-eighth scale model of the EMD F7 Diesel-electric locomotive
. At 900 pounds and with 16 horsepower, it can haul a train carrying 20 passengers. It's not finished, mostly due to the aforementioned health issues, but also because I keep tinkering with the propulsion system. This too will help to slow down brain rot as I age.
Edit: Forgot to mention that I'm a classically-trained double bassist, but mostly play blues, jazz and occasionally jam with the hillbillies