As I mentioned in my last post, my father worked on electronics in the Air Force. At the time I was born he was working for Motorola, but he didn’t feel like he was making enough money to support a family. When he saw an ad saying IBM was hiring he applied, and convinced my Uncle Lee to apply too. They showed up for a day of testing and interviews with about 80 other candidates, but at the end of the day only my father and Uncle Lee were hired.

Since I work on IBM z computers, the modern descendants of the IBM System/360, I decided to ask him several years ago for stories about the early days of that architecture. Most of his stories weren’t about things he did, but he did tell me that one time he was working on a communication program, and his manager had arranged test time in the middle of the night on a customer’s computer. They had loaded their software onto a tape, but they had been given the wrong address for the tape drive, so after loading the first part of the program when it tried to read the tape the operation failed. The manager started ranting and railing about how much time and money he had spent setting up the test and flying his team to the test site, which would now be totally wasted and would set their project back weeks. (I think he said the manager was also blaming the problem on the female workers who had prepared the tape.) While this was going on, my father quietly went over to the console, found the memory location where the tape unit address was stored, altered it to contain the correct address, and then turned around and said, “Let’s try it again.” He restarted the program and the test was able to proceed as planned.


IBM System/360 model 30 console at the Computer History Museum. Photo by Carlo Nardone; accessed from Wikimedia Commons. Used under the Creative Commons Attribution-Share Alike 2.0 Generic license.

I regret that it didn’t occur to me to ask him about his work at JPL. It’s cool to think, though, that code he helped write might be executing outside the heliopause in interstellar space.

When we lived in Houston he was working on the computers that were to become the onboard processors for the Space Shuttle. From what I remember, they were developing a new programming language (named “HAL”) to write the software, and the compiler was new and untested. My father’s job was to debug programs that weren’t working and determine if the program had been written incorrectly or if there was a bug in the compiler. One time for MIA we had a series of meetings where men in the ward came and talked about their jobs, and my father was one of the ones who did this. I was pretty impressed when he started writing down instructions in machine code from memory. (Having since then had to do some debugging of my own, I’m not as impressed as I was then. It was still cool, though.)

After he left IBM he worked for a microcomputer company named Billings Computers, where he headed up their systems programming division. This meant we were one of the few households at that time that had multiple computers in our home. While he was at Billings I left for Texas, so I’m not as familiar with what he did after that. I know that the last few years before he retired he was working for Novell, where he led the team that certified third party hardware and software to work with Netware.


For completeness, here are some other stories he told me about the early days of System/360:

IBM salesmen had a base salary and an annual quota. To get the full base salary they had to meet the quota, but if they exceeded their quota they were compensated at a much higher rate. Now, the System/360 project had been kept secret, but at the beginning of 1964 the salesmen were all given quotas substantially larger than what they’d had in 1963, I think he said about twice as high, and there was a lot of grumbling from the sales force. Then in April the System/360 was announced, and most of the salesmen had made their new, higher quotas by June. So they went from very unhappy at the beginning of the year to quite pleased and wealthy by the end of it. Technical staff like my father were given a two week technical briefing right before the announcement.

The System/360 model 30 of course by default ran System/360 programs, but you could change the microcode and it would run programs written for the 1401, IBM’s previous line of business computers. Technology had progressed so far that it ran 1401 programs twice as fast as an actual 1401. Our neighbor across the street in San Jose worked for a competitor that made what we’d now call 1401 “clones”, and he was quite discouraged when he found out how fast the model 30 was. (Erick and Hans probably remember this neighbor’s son, Eddie Baker “Snake”, who was about our age.)

One of the customers my father worked with had a set of 1401s that they were looking to replace with 360-30s, but their 1401s had been purchased with what’s called an RPQ (Request Price Quote, I think) that added a special instruction to the hardware. (Yes, in those days you could pay extra and get a modified instruction set for your computer.) The standard 1401 emulation code didn’t support that instruction, of course, so IBM flew in their microcode expert to see what could be done. He asked what the instruction operation code was, so they told him, and then he sat down with some paper and did a bunch of calculating and then said, “If you do that it should rewind the tape drive and unload the tape.” “Yes,” my father said, “that’s what happens.” “Well, what do they want it to do?” So they told him, and he did some more calculations, then pulled out some blank, copper-clad punch cards (that was what the microcode was stored on) and a hole punch, punched some holes in a handful of cards, used the new cards to replace some of the ones in the computer, and said, “Now try it.” They did, and everything ran just like they wanted it to.