4-bits, 8-bits, and a dollar!: Recent Episodes
Gary Moore
True stories about technologies I've used over the past fifty years. From 4-bit, Intel 4004 microprocessors to the marvel of op-amps to building an interface to an HP-3000 in a rat-infested animal feed company.
The product was called Callback/3000, kind of like that satirical tv show, "Mystery Science Theater 3000." MST3K premiered on November 24, 1988. My product premiered in the early 1980s! The "3000" in my product's name stood for HP-3000, the minicomputer manufactured and marketed during those years.
When I was the Product Manager for a software company, we received an invitation to demonstrate our product to a client. We had a new version of our flagship product. To say it was "wobbly" would be an understatement. The first part of our presentation was the typical PowerPoint. Our client asked a few questions but just wanted us to move to the demo; that's when the fun began.
When I owned an R&D and manufacturing company, I was asked to build a tension control for chill-rolls on Harris web presses. My radical approach was to use optical encoders instead of tension sensors. It worked like a dream!
Today I talk about the time I was called on to work on a machine that was too hot to touch. The moment I opened the door to the factory, I immediately thought of Dante's Vestibule of hell, the one with the gate that bears an inscription "Abandon all hope, ye who enter here."
My first experience with debilitating heat was when I was given a project to install a wireless language lab in school buses. This was an experiment. A school board wanted to try to create a way for kids that had very long commutes to school to officially fulfill one class.
Instead of high school kids wasting time in a bus for two hours each day, they could learn a language and get credit for it. I thought it was a great idea. I just didn't appreciate how difficult it would be to make their vision a reality.
If you've ever watched a rock concert, you may have noticed the lead guitar player using several foot-actuated devices to change the sound of their guitar. And, if you are old enough to have bought the Beatles' Rubber Soul album, you may have noticed in the liner notes that Paul played "fuzz bass" on "Think for Yourself." Paul firmly established the use of guitar pedals in rock music.
So, today, I want to tell you about a PLC project I did for a large industrial factory during the mid-1980s.
The purpose of the project was to replace a set of mechanical relays and discreet analog devices with a programmable process that would control solid-state relays and replace a bunch of individual temperature controllers and load cell PID controllers. I used a Gould Modicon PLC for the project.
It was an interesting challenge, especially because the company didn't have any schematics for the existing system. The first thing I had to do was figure out what was going on, and build out a set of schematics based on my observations. Many times during this effort, I sat down with engineers that knew what should be taking place. I showed them what I thought was actually taking place. Both the company's engineers and I would often be shaking our heads as we walked away from these meetings.
During the 1990s, I had built a large enough network of people that I could contract myself out for short-term programming jobs. One of the jobs was a six-month contract to help finish a call center for an electric company in Pineville, Louisiana. The application we developed for the customer service representatives (CSPs) was written using the PowerBuilder programming language. The interactive voice response (IVR) program was a commercial application that ran on an IBM AS400. And some single-purpose apps were a mix of commercial software and custom software written in C++.
In the early 1980s, I led a fun project paid for by the state of Indiana. The intent was to create a synergy between academia and private-sector technology companies. These kinds of partnerships are very common today, but in the 1980s it was very bleeding-edge. The goal of the project was to create a computer program that would create customer-specific configurations based on every possible configuration of the company's existing products. The hope was that most, if not all, customer needs could be satisfied by the CPU boards, memory boards, general I/O boards and so forth. All without having to build any customer-specific boards.
Every programming language has a set of standards prescribing how variable names, function names, class names, and so forth should be structured. For variable names, COBOL uses hyphens (-) and Pascal uses PascalCase. Some languages use camelCase and some use snake_case.
Today I'm tell my story about being bitten by snake_case.
Today, I am walking you through what it took me to make an industrial product in the early 1980s. This is what I did for one of the most uncomplicated products I ever sold. It was an RS-232 to RS-422 converter. It just used a couple of integrated circuits, a few passive components (clamping diodes and capacitors), and a power supply.
I was a manufacturing Engineer for Zenith and worked with the System 3 television when it was first released. The System 3 was the first product Zenith designed without an isolation transformer. This seemed to terrify Underwriters Laboratories® (UL®).
The R&D lab that I worked for purchased a couple of Rockwell AIM-65 single board computers. The AIM-65 used the 6502 microprocessor, and it had a built-in keyboard and 20 character printer. The printers were super helpful when debugging programs. The 6502 microprocessor powered the Commodore PET, the Apple II, and the Atari 2600 game console.
Titanium dioxide is used to make plastic film brilliant white. For the R&D lab that for, I designed and built a device to measure the concentration of titanium dioxide in plastic film. Coming up with the idea, designing it and building it helped me realize that I really enjoyed building devices. This eventually led me to starting my own company that focused on developing marketable electronic devices.
Who doesn't like a good explosion? That's why the Die Hard movie series has been so successful. Well, my story doesn't match John McCain's, but it was plenty of excitement for me.
If you've ever seen or heard a cassette tape or an 8-track tape or bought a blank cassette tape, then there's a high probability that I worked on the machine that made it. Early on in my career, I was an electronics technician, and for five years I worked for Columbia Broadcasting Systems (CBS) in their cassette and 8-track tape factory - wow, do I have some stories!
In my previous podcast I spoke about the time I measured the voltage on a corona bar, a real one, not the beer. For this same company, I was challenged to design a safety device. I did, but it was the catalyst that nearly got me fired!
Today's story is about when I worked in an R&D lab for a plastics company. I needed to take some measurements across a corona bar. The corona was 80 kV at frequencies between 15-25 kHz. It was fun, but my on-lookers made me a bit nervous.
I flew from Chicago to Milan and was then driven to San Martina Del Rio, a small town with a population of about 8,000. I was there to install a computer-based machine control system I'd built. Wow, was I in for a surprise with I walked into the printing plant!
In this episode, I'm talking about when I was a full-time instructor in advanced industrial electronics for Indiana Vocational Technical College (IVY Tech). For one of my labs, I challenged my students to build an analog amplifier from a 7405 TTL logic chip. It was a blast!
In the beginning of the computer revolution, information about semiconductors (microprocessors, A/D converters, RAM, DRAM, EPROM, etc.) was only available in books that the semiconductor manufacturers printed. The semiconductor representatives were the lifeblood of our revolution!
I just skimmed the Wikipedia entry for the Cromemco [a]. Apparently, the Cromemco computer was known for its reliability. That was not my personal experience. However, I was wrong about the bus voltages. The S-100 bus [b] had bulk unregulated +8 Volt DC and ±16 Volt DC. It was an oven mounted with floppy drives!
[a] Cromemco - Wikipedia
[b] S-100 bus - Wikipedia
I built several projects using the Intel 8085, and I built one product. The product was very successful and it never experienced an race conditions or deadlocks. It was highly stable because I used a dead simple approach. That's what I'm talking about in this podcast. I hope you find it interesting.
Back in the 1970s and early 1980s programmers (i.e. developers, software engineers, etc.) had fun writing code. Working on PCs and SBCs, we were in a new world. We had to create this innovative technology, and there weren't any standards for writing comments, so we had fun with them.
Is it wrong for an unsupervised 10-year-old kid to make a solar cell using asbestos, phosphorous, and a 2,600-degree furnace? Well, it turned out fine for me, but I never let any of my kids even come close to doing this.
I tell a story about creating a device that interfaced a minicomputer to a machine that created three million volts to simulate a lightning strike.
To reminisce means to indulge in an enjoyable recollection of past events. Since I actually grew up in technology, I've decided to share some of my memories. For me, I've had a wonderful time. I began learning electronics and computer programming when I was ten years old. My dad was a professor at Bradley University so, on weekends, he'd go in to prepare for his classes and I had the full run of the labs and even access to the IBM mainframe. Life was great!
Today's memory is of my experience in troubleshooting what, today, we'd call a single board computer. However, it was a 4-bit computer with 256 bits of memory! I hope you enjoy my memory.