Embedded - 376: Left Half of My Brain Is Digital

Episode Date: June 10, 2021

From his view in retirement, David Comer spoke with us about continuing to learn, staying engaged in an engineering career, and how the Galileo memory module worked.

Welcome to Embedded. I am Alicia White alongside Christopher White. We're going to talk to David Kummer, an engineer whose career spans from Galileo missions to today. Hi, Dave. Welcome to the show. Thank you. Could you tell us about yourself? Well, how many hours is this again?

No. So I actually spanned prior to Apollo. I got into electronics when I was six years old, believe it or not, and it wasn't serious at that point. My folks and I, my sister and I, family was down in, whatchamacallit, Disney World in Florida. And I watched a DJ in a booth, and I thought, this is what I want to do. So I knew what I wanted to do from age six. I actually started building. Yeah, I thought, you know, all that equipment looks really cool.

You know, I thought maybe that would be fun. And the DJ part was appealing because, I thought maybe that would be fun. And the DJ part was appealing because, hey, here's this famous person. He had no idea what he was saying, but it looked cool. The thing that catch for me was really the equipment behind and what was going on. So I started experimenting. These are probably way before your time, but the Radio shack p boxes do you ever remember those or heard of them i probably do but i it's probably lost to memory i didn't grow up with electronics so oh well way back when radio shack had these little boxes and they're basically

before heath kid or maybe thereabouts and so you put them together and you build them. And so I would do things like try to build radio transmitters in the garage. And I learned about rectifiers by touching a live rectifier, not realizing it was charged. So I learned that I prefer 25 volts or less. It's good to get that number established early in life, you know, what your threshold is. I actually, in high school, built a radio station, not by myself. We had a second-class radio engineer build the transmitter. It was called a carrier current.

Later on, I got into a public radio station in town called KANW in Albuquerque. It gave you experience. And from there, a lot of kids went to the big K, it's now called KKOB 770. I went to KOB, but not AM. If I'd gone to AM, maybe I'd be famous, probably not. But I went to FM, got into FM radio, which was Muzak back then. You change tapes, you do newscasts in the middle of the night, and you sleep in between the tapes as a student in high school. Why does that sound so romantic to me?

It's a cool nostalgia. But it probably wasn't that fun, was it? Well, it wasn't WKRP in Cincinnati, but it was close. I would have preferred that Lonnie Anderson was there, but of course not. So anyway, from there, I went to KERS in Berlin, which is a 500-watt radio station. Berlin is like 60, no, not 60, probably 40 miles from Albuquerque, and worked there on the weekends. Got myself into trouble once because I wanted to fix their, they call them carts, their 8-track players that played commercials.

And I was trying to figure out how to have a tight radio show. And I finally decided, you know, I should take this cart apart and put a button in it so that I can cue it. And I did that, and I came back the next weekend and found out I was in big trouble because the engineer had been in. And he said he could have destroyed this. It was total horse pucky at that time. But they were pretty cool. But I went to New Mexico State, and that was where it really, really took off.

So actually, to make a long story short, I got into space systems and stuff like that as a co-op. And later on, I got into the semiconductor industry. And later on, before I retired, I was working for a national lab. So I've been in electronics all my life. Okay. And you have done silicon and hardware and software, right? I have. I used to design chips. What kind of chips did you design? The 74HC family, which is the successor to the 74LS, high-speed CMOS. So those were a series of logic gates. It's what you built computers before microprocessors came about. And I did that at Texas Instruments. Okay, so I have more questions about that.

But I actually want to talk about your career as a whole. But before that, I want to do a lightning round where we're going to ask you short questions. And we want short answers unless we don't, in which case, go on. No problem. What programming language did you learn first? Actually, let's see. It was either assembly or basic.

Let's say basic. What programming language do you think new college grads should know now? Not just one, many. Python, Go is a popular one. C and C++ are always good, but there are more that I haven't gotten into, but those are the ones I would recommend. What is your ham call sign? NM5DC, New Mexico 5, Dave Comer. Nice. Do you have a preferred way to learn new technical things reading videos trying out without reading the docs yes all the above i uh webcasts reading um buying a book working through it um you name it i'll i'll do anything to learn a new technology. Favorite non-terrestrial object in the solar system?

Computer. Okay. Do you have a favorite bug from your career? Probably a software bug, but I don't know, grasshoppers when I was a kid. Do you like to complete one project or start a dozen? Oh, a dozen. I can't decide what I want to be when I was a kid, but you just put your heads off. Do you like to complete one project or start a dozen? Oh, a dozen. I can't decide what I want to be when I grow up. Do you have a tip everyone should know? Yeah, if you ever have ice cream freeze, take your tongue and stick it to the roof of your mouth

and hold it there, and that'll cure it. All right, that seems really useful. We're going to have to go out for ice cream after this, Christopher. All right. That seems really useful. We're going to have to go for ice cream after this, Christopher. All right. Okay. You mentioned you were retired. What does retirement mean for you? Taking care of my wife, believe it or not. It wasn't a decision that I thought long about. There's a long story behind that. I won't go into it other than to say she had a stroke and here I am. But you're still doing technical things. Oh, yeah.

What kind of technical things? Well, I do software-defined radios, something I'm into, embedded programming, playing with Laura. I've got a whole series of gadgets sitting in front of me. So on a day, I just get up and decide what I want to play with. And I'm working towards an eventual software-defined radio design. How do you stay motivated to keep working in tech? I have a paranoia that if I fall behind, it will become non-relevant. So I always keep my education up. And always, I have 100 terabytes, sorry, of library that I'm always building and adding in case I need a reference library.

And so for the software-defined radio, are you working on an existing platform, or are you making your own hardware and software? I'm playing with the HackRF. I'm playing with the UHD, the National Instruments. I can't remember what the—oh, Edis. I'm playing with Elector Electronics has a software radio design that works with the Adreno. But pretty much, I'm working with my own design. And is it the software part that's fun or the hardware part that you can do anything with radio part? Oh, both, both. I like to say my left half, my brain is digital and the right half was software actually. And the right half is hardware. So I work on both sides of the fence.

Where do you see that going? The SDR stuff? I paid a little bit of attention to it a few years ago. And then like a lot of amateur radio, people fell out of amateur radio to do other things. I keep thinking of coming back, but where do you, where do you see that heading?

Like replacing large amounts of hardware or enabling new capabilities? Pretty much enabling capabilities all the way from military down the way to personal. Xilinx has new chips coming out that I think are going to drive direct, well, you already have direct toto-baseband ADDs. And with FPGAs they're incorporating in, I think there's a lot of really cool avenues opening up. I think they're going to overtake microprocessors at some point, but I could be nuts.

In terms of? Well, in terms of performance, in terms of scaling, today's chips, if you look at them, they would require a room full of circuit boards. In the days when I started growing up now with SOICs, you can get almost anything you want. And if you don't have it and you have enough money, you can build it. Gotcha. So do you mean FPGAs replacing microcontrollers or like the PSOC where it's a combination? Think of it in terms of like a zinc. I mentioned Xilinx.

Altair is also a very good FPGA, and there are others. But the ARM9 being integrated into the zinc several years ago was a hint to me to multiple cores and FPGAs. They go together. Way back when, when I started on the 8051, I used to design on that for Cignetics. We used to have a group that sat around and came up with new ideas. And I kept thinking, why can't we put a RAM in to make it reconfigurable? And that's exactly what they have today in FPGAs with a better processor, though. Were there things you've seen over the years that you've thought, okay, we should do this, and then a few years later somebody finally does it?

Yeah, I've got a short story on that. Inside almost every microcontroller you find today, a PLL. And in those days, you know, you're talking probably 1 megahertz to 10 megahertz. And I thought, well, why doesn't somebody put a PLL in these things? And you can essentially have any frequency you want. And I talked to some people about it. I just didn't have the knowledge to do PLLs. And had I been more proactive, I could have had the patent on that. How do you figure out which new technologies you should really investigate as opposed to trying to not spend too much time on things that seem fly by night? Oh, that's a great question because I still haven't figured

it out. I mean, I've got Laura sitting here. I've got Arduino, which is, you know, that's archaic by today. Bluetooth. I've got almost every technology, even analog, in front of me. And so I go between all of them. So that's probably one of my shortcomings is I like working on everything and nobody can do everything. And I try to do it. So if you saw my workbench, you know, it's a sign of a sick person. It's really filthy. It's a sign of a busy person. An entrepreneur, I guess, would be a nice way to put it. How do you manage to keep working with new and interesting technologies instead of being the in-house expert on legacy technology and products?

You know, pretty much reading and researching. To me, new technology isn't necessarily building the hardware. It's more reading about circuits and systems. Circuits and systems is a love of mine and understanding the mathematics and how things work behind the scenes and trying to apply them. But I like sharing. I'm not really one of those people that's going to build the next Microsoft. In my days, it was you show people how to do things you teach. So probably teaching would be a great avenue to do that. And so in your career, have you been in a position where it looks like you're going to be stuck on legacy stuff forever? And how do you get out of that?

Oh, yeah. I used to work for electrosonics and they're an albuquerque firm that builds wireless microphones and digital mixers and i started i worked for them for a little while i was building the software for and customers to um program the uh the mixers and we're talking not audio mixers in the sense of concert mixers. We're talking about digital conference mixers that you see in big boardrooms. And I was boxed into writing the software, and I get bored really quick. So after about a year and a half, I wanted to get into the embedded and was told, no, I can't. We need you to stay on this for, you know, foreseeable future. And I'm a renegade. So the way I get out of stuff like that is I, first of all, I have my resumes diverse enough that I can go pretty much anywhere and put it out

and they'll say, wow, we can use this or we can use that. So I'll just, you know, do a job search. And some people are afraid to leave jobs I'm not. I take it as a challenge. And so my career, you know, you see a lot of my jobs and some have asked about job hopping and I always say, no, I've got to have the next challenge, you know, in front of me. So. What was the longest you stayed at a company? 13 years at Signetics, which was actually owned by Philips. And I went from Signetics to Philips, back to Signetics and Philips, because they had different opportunities. Semiconductors, you do that a lot, primarily because it's a very cyclical business. How do you decide when to leave a company? If you start getting cranky or...

Wait a minute. You can't quit. You're co-owner of this company. Other companies. I start out cranky at other companies. Well, you start to get... What's the word I'm looking for? Bored? Bored is a key one, but you start talking bad about the company and you don't

want to get there. That's a bad place to be. I actually got to that point at Intel to the point where I was telling the manager, you really ought to lay off this department. We aren't doing anything useful. And I'm honest, I'll be straight up. And that's probably what did me in because my next review was not good. And I said, that's okay. So it turned out they gave me what's called a cap, a corrective action program. And I thought this is cool because they say they'll buy you out. And I took a buyout. I got a $10,000 bonus for leaving the company and signed on with another company the very same day. So, you know, you can make money off of leaving companies,

but I don't recommend doing that. It's not something that's wise to do because you don't want to get a bad reputation. But I've had a great reputation all my career, as far as I know. You'll always find people that don't agree with you. You'll find as you get older, when you're working for younger bosses, you'll kind of wonder, you know, do I really need to be here? But, you know, there's always never stop dreaming for the future. Don't get complacent.

How do you deal with the situation where you're thinking, I have t-shirts older than my co-workers or older than my boss? Well, let's see. Do you guys know who Paul McCartney is? Yes. I met him once. So, I actually have, well, no, I didn't. My ex-wife has this now. I had an old T-shirt from his Australian tour, which was a pride, and she used it as a night shirt.

But, you know, I don't think anybody knows, very few people today know, they kind of know Paul McCartney and the Beatles, but I've got T-shirts that go back to the 60s and 70s. So, you know, you just don't try to go into too deep with, you know, people that don't know who it is because you can bore people. But how do you interact with the youngins? Has that changed from beginning career to mid-career to late career? Oh, yeah. As you get early in the career, you're competing with the young'uns because you're one of them. Mid-career, you're thinking, well, should I go in to be a manager? And for me, it was like, yeah, hell no. And then later on, I always stayed the technical ladder.

And I realized at some point I was probably going to become lacking in newer technology. And boy, did I learn that later than sooner. But you listen to young kids. And I'd call kids, anybody under 30 to me as a kid. I'm actually going to be 63 this month. So you have to listen because when I came out of college, I knew everything. When they come out of college, they know everything. But you know what?

They do know a lot of good stuff, and to not listen to what they're telling you is foolish. So you listen to what they say. If you're in a position – well, actually, I was recently just before I retired. There were a couple of guys that I was supposed to be helping along on a project at my last position. And they had no idea of the terminology that I was talking about. It was kind of key for what they were doing. And I kind of moved them on to somebody else because they really didn't want to learn. They knew it all. And they really didn't want to understand the purpose of what they were doing. So I'll cut my losses if I have to.

But on the other hand, those that want to learn, those that are anxious and say, give me something, give me something, here you go. Dig a hole as deep as you want and, you know, have fun with it. And if you need help, let me know. But don't micromanage. I think the diversity of thought that comes from young people who haven't seen everything is great because they'll have new ideas. But oftentimes they'll have the same ideas that people had 30 years ago and present them as new with a new name. Have you dealt with that in the past? And how do you politely say, you know, we were doing that in 1985 or something? Well, that's kind of funny you should ask, because there's a blog I was reading just last night.

We'll see something. I wish I could remember it. And he had a comment on there. He was talking about KiCad, the schematic editor, the open source. And he said, you know, I was looking for a squiggly resistor to put in there um but you know you don't just snap back at somebody and and whatever you kind of politely find a way to um tell them no that's not true the i the ieee came out with a new set of box not a new set back in the 70s came out with a schematic set that they tried to push so i'm not really sure what this individual was saying, but I'm looking at a schematic now that has squiggly lines and it's brand new. So, you know, some people I think you have to realize they're off the cuff and they're just trying to sound

important. Other people may not know, but you shouldn't demean somebody for something they say. You should try to understand where they're coming from. Now, my wife will tell you, I wish you'd practice what you're preaching, but you have to have patience with people that are learning because to them, everything's new and nobody's invented it. I mean, gosh, when I got out of school, out of college, I wanted to build the first digital stereo and so did everybody else. And today, you know, that's boring. So what younger kids are going to be inventing, I'm hoping will be something like three-dimensional conferencing. I'm surprised we haven't seen that. If you look at that Mars mission at the recent Embedded Conference, what they did there is incredible.

I mean, oh my gosh, I wish I were working on that. So, you know, there's always something better coming along. The atomic bomb didn't exist, you know, in the 40s. I mean, nobody wants an atomic bomb, but look at the effort that went into that. So anyway, I digress. It sounds like your advice for interacting with the kids is both to listen to them and to hope that they're willing to let you teach them. Combination. If they don't want to be taught to, I don't want to be seen as that old codger, that silver guy that is ready to retire. Don't listen to him.

He'll cranky and tell you all these stories about the good old days. More stories about what you did. It'll go only so far. But you can use that information not to tell them, oh, this is how we did it. But have you ever thought about doing it like this? You have to get into their head with anybody. And the term kids probably isn't appropriate because these are young people that are out of college. They're not kids. They're not eight, nine-year-olds. But even younger kids that are six or seven years old, they're learning and you don't want

to discourage them. And there's too many times in my career when I've been working on something, and somebody will say, that won't work, tried it, been there, done it, don't do it. And it's like, you know, don't do that. Don't discourage people. Give them ideas, give them guidance, and let them create. Let them figure out what voltage they... What is your... Oh, there used to be a commercial. I can't remember what it is,

but what is your max voltage? Exactly. Some of these people are in megawatts. Just as an aside, I had a very good co-worker that was into Tesla coils, and he was up in the 10-megavolt range in his garage, almost killed somebody. But it's a funny story. Okay, so your approach to the younger set has changed over your career. How about your approach to jerks? The people who aren't helpful, the people who are just jerks. If you've ever read any of Dale Carnegie's stuff, and that stuff is pretty dated, but it holds true today. You know, starting a fight with somebody, well, I'll tell you,

politics will get you in an argument. You should never discuss politics at work. That's one thing that will get you in trouble, could get you fired. It doesn't belong at work. I had a co-worker that was really hot to talk politics. He was very passionate. And I could see where it was headed. It was almost headed to, you know, the finger pointing. I finally said, you know, co-worker, how about if I pick out an article that, you know, I think you would like to read and you do the same and we'll discuss it. And that kind of settled it right there because he wasn't willing to do that. And so he realized, you know, you kind of diplomatically get around stuff like that. But if you avoid confrontation, and I don't mean wimp out. You always have to have confrontation. Maybe somebody's got a design that's going to kill somebody. You have to stop it and say, no, we need to talk about

this. But you don't point fingers. You don't, well, you shoulda, I shoulda, or I told you so. You try to, Intel was really good about that internally, getting people to work together. And other companies have. Some other companies were confrontational. But everybody has feelings. And, you know, everybody has pride in what they do. And if you immediately come in and start accusing or saying you screwed up, that's the best way to lose their interest. So that's what Dale Carnegie used to preach is you treat people like you'd like to be treated.

That's a nice idea. It's not always so easy. Well, this goes back to the Beatles, but if you ever listen to George Harrison's Outlook on Life, I could tell you a really funny story along those lines. But he treated people really nice. Here's a famous guy. And if you ever have a chance, watch the film Living in a Material World. I always liked him. But after I saw that movie, I was like, wow.

He was my favorite Beatle after then because of the way he approached people's life. He was kind. He had a good outlook on life, so he was probably a good role model for me in my later life. This is actually before I met my wife now. And so I kind of look at it like that. As you treat people nicely, you know, I've been a total jerk to other people. And, you know, it keeps with you the rest of your life. And you don't want to have those memories as you get older. It's true that the times that I have acted poorly, I regret more than I would like to.

I mean, I wish I could go back and tell myself, no, no, no, this is not the right way. You can't take it back either, but you don't want to dwell on it. Has the social part, the human part of engineering changed over your career? Definitely. Social media, for one, although it's not the hands-on electronics. But the internet came along, I think it was 1988, when we finally got fiber in Albuquerque. And nobody really understood it. But now it's like Twitter. You have so many social platforms, it's ridiculous. But the interaction, especially when I was in college, it's like, how come there's only males in engineering? Where are all the women?

All the electrical engineers would say, yeah, you know, the College of Business has plenty of females. Why don't we have females? And it's because it was a male-dominated area. And that's changed. If you look at NASA and, you know, again, going back to that conference and you look around the room and you see the type of people that are leading and are involved, it's totally different. It's really nice. It's, you know, it's all inclusive. Has it been hard for you? I know it's been hard for a lot of people.

Has it been hard for you? And if so, why, how, and how did you get over it? Oh, no. No, I adapted easily. The male back in the, I don't know how far back it goes, but at least until the 70s when women started in engineering and being around, I think a lot of people had a bias in them. It wasn't obvious. I mean, with the EEOC laws and stuff like that, I think that facilitated it. But there were so many different variety of people from other countries, other sexes,

things like that that got into it that you just accepted it and you found that, hey, some of these people are pretty damn smart. One of the smartest persons I ever met was a gentleman from Hungary. And he was a PhD and taught me more than anything else in the world that I can't tell you how in debt I am to him for some of the things that I learned. But you learn from all kinds of people. And when you bias people out because of who they are or what they might be, and you don't get to know them. I mean, how many times you met somebody and you hate them instantly, and then you find out later, wow, this is a really good person. What was I thinking? I mean, that's happened to

me. So you learn to accept people and give them a chance, you know, not prejudge. Now, I'm not always practicing what I preach, but to me, that's the best way to approach it. It's sometimes hard for me not to prejudge, but as I go on, I try not to act on that judgment. You know, it is hard. You have to catch yourself, I think, and realize what's happening, or you have to have prior experiences. Everybody's going to have a horrible experience in their life. I mean, you can't avoid it. What you can do is try to minimize those experiences by learning from them and drawing upon attention. One of the reasons I can come up with answers so quick is I'm constantly, I have self-talk all the time.

And I started that when I started doing, what do they call them, behavioral interviews. And so I draw upon my experience all the time. And I've learned from all those experiences. I forget a lot. And then I remember, oh, yeah, I forgot I did this or that. So you need the experience to have done poorly or badly at one time by somebody. And then you remember what it is and you tell yourself, don't do that again. So I'm not sure that's a good answer, but it's the only one I can make up.

Well, sometimes if you can't be a good example, you can be a horrible warning, if only to yourself. True. I guess I could draw upon the experience I had when my wife had the stroke. A couple of years ago, I won't dive into that too much. But when you come home and you find a loved one almost dead and you don't have any experience with that, what do you do? You know, you learn about yourself. You learn the inner self. What can I do and what can't I do?

And you go with it. So as it turned out, it worked out really well. But there are challenges in life you're not prepared for that you just have to take them as they come and do the best you can. That would be very tough. I mean, I think that would be tough for anybody. And I don't know that anybody could prepare for that sort of thing. Oh, you can't. But, you know, instead of, there's a little bit of insight when you go into a facility, a rehab or an ICU,

where there are people like that, you'll see people that can't handle it and they will abandon their loved one, spouse, whatever. Other people will sit there and say, well, it's not my job. That's why the medical people are there. And then you'll take the approach that I did and that's show me how to do it. I have to take care of her when I get her home. How do I change her briefs? How do I do this? How do I do that? How do I teach her to walk again? Blah, blah, blah. I mean, just recently in the pandemic, if you want a good example, the rehabs were shutting down because you couldn't go into the outpatient with COVID. So I built a rehab in our house and we weren't going to stop. We just kept going forward. So I guess from that, you learn, don't give up, keep going. Engineering is great, by the way, for that situation, because if you're a systems engineer,

you can explain to your spouse how her brain is working and why she can't do this and that. So it's true. You know, I gave her a whole lecture on feedback systems and why it was hard for her to eat. So she took it really well. She's a geek kind of like I am. But I learned from my experience, take what I know and adapt it. Somebody told me early on in my career that just because you're an electrical engineer doesn't mean you can't be mechanical, chemical. You go to college to learn how to learn. And you can do anything you want. You just don't say, I don't know this, so I'm not college to learn how to learn. And you can do anything you want. You just don't say,

I don't know this, so I'm not going to learn it. That's important, that willingness to learn and that resistance to, oh, I don't know it and it's too hard. I'm not going to bother. I feel like with engineering, we learn that resilience is a skill. Oh, yeah. The part where you say, oh, this is hard, and then you walk away for a little bit, and then you're like, but I'm curious, so, you know, I'll just push through. Well, think about the mistakes that were made on the Mars. I'm keen on Mars because of Galileo, because I feel a special attachment to it, because that's the one thing you can say, hey, I did something. I went to another planet. But the folks that made the mistake between English and metric units and they lost the

spacecraft, you know, did they give up? Did they quit? Did they, you know, say, I'll never do this again? You know, everybody makes a mistake. In my career, something more, am I closer to a lie? Their mistake, by the way, was naming their probe Beagle, because if they had ever met a Beagle, they would know that it would not go wherever you wanted it to. That's a good analogy. Not like a collie right um it's just funny though because people make mistakes and if they if you

get punished it i mean that's a big mistake that was what um probably 100 million dollars or more but if you think back to the days of the the initial uh atlas rocket and the rocket engineers that were launching and, you know, they would launch these things and they would blow up. Well, that was expected. And I mean, space exploration is really way different than, you know, most things because the things they're doing, you have to spend a lot of money to figure this stuff out. But in everyday stuff, people make mistakes all the time. And, you know, you have people that'll take it hard. You have people that'll handle it with anger. But you should never encourage, you know, you should try to understand and, you know,

be compassionate to some degree, depending on what they do. But, you know, you should never over-criticize somebody. I've been responsible for losing probably $100,000 on one product I did at TI because I had to redo a mass set. And nobody came to me and said, you know, you screwed up. Although they did later at Signetics, but that's another story. You know, sometimes you just make a mistake, you fix it. But if you keep repeating it, then you need to, you know, somebody needs to work with you to show you what's going wrong. But anyway, I digress again. I'm good at digressing. Sometimes I wish I knew then what I know now about engineering and the times that I was impatient when I was young.

Because your example of the Beagle Mars probe that was... It wasn't the Beagle, by the way. That was a different failure. Was that it? I thought that was the... No, no, that was the British probe that landed but didn't unfurl its solar panels. I just don't want you to impugn the wrong. The meters versus miles per hour, or the kilometers versus miles. I see that.

I have a simulator where we're working on AI stuff. And in my simulator, this half is in meters and that half is in miles per hour. So I didn't build the simulator. This is not my fault. It would all be in meters if it was up to me. But I can understand now how that happened, how the separate parts of a project just assumed that everybody thought the way they did, and how I need to be the sort of person that will check some of those assumptions

and to go in and say, oh, that's really cool. Are you sure you're doing meters and you're doing miles per hour? If you consider it a conversion, sort of oil over the water action. Do you get to do that very much or have you gotten to do that very much, or have you gotten to do that very much, or is it a matter of just finding the problems? It's a matter of the system. I suspect what happened to them was the system failed them, and that's one thing NASA has noted for the checklist, check, recheck, and dating all the way back to Apollo 11, the sheets, of course,

when they had the problem, they had it invented as they were there in Apollo 13 the same way. But that's what testability, that's what build-to-test, that's what a lot of the systems – I'm sorry, I'm at a loss for a lot of acronyms right now, but that's why you have the balance and checks where standards and procedures and check-in, check-out, and I'm kind of reaching the far gambit of what you do in software, but there ought to be something that says, you know, you put the units in with what you're putting in, and something should flag you like a Mathematica, not Mathematica, Mathcad. And this is very simplistic, but Mathcad will check units. Well, you know, it seems to me that there should have been some unit checking and something that made sensibility. As an engineer, you should look at numbers and be able to judge for yourself whether this makes sense you know like is it 100 million miles to the local

uh tgny uh that's they don't have this anymore to the local uh circle k or dime store whatever um no it's not 100 million miles maybe it's one mile somebody's off by six orders of magnitude so i would suspect that the it was more of a systemic problem than one engineer or group of engineers making the mistake. So, you know, that's why you have different evolving standards. And that standards are good. Some people consider them, you know, they try to get around them because they're too many. But when you're dealing with that kind of money and safety especially, there's not enough checking you can do because you could be killing somebody if you're not careful. So going back to the Galileo probe and this sort of you have to design with high consideration because the chance of failure is very expensive.

What kind of design considerations did you have to consider? Well, I'll tell you a story about that. I was working on the, it was called the memory control system, the d-spin section of the Galileo probe. I don't know, you guys sound like you're probably pretty savvy on space, but every satellite, the Voyager and everything else had a spin and a d-spin section for stability. So the part I worked on was called the d-spin. And so it's not the real sexy part, the actual instrumentation, but it was an attitude control system to keep the probe from being like a gyroscope and spinning through space. And the individual I was working with, it was quite interesting.

At those days, you could smoke in the laboratory. And when I first met this guy, he's standing over this chassis with a cigarette in his mouth and ashes pouring into a wire-wrapped fixture. It was a prototype. It wasn't something that was going out. But when I saw that, I was in horror and learned that what he did when the people came around in the lab to check things, he would take the cigarette ashes and put them in a drawer, you know, out of sight. So, I'm sorry, I kind of took your question around with that.

But you learn things like that. Of course, I never smoked, but I would never, you know, I had to make a decision right there and then. Do I go to the manager and say, you know, this person was doing that? I could have ruined the guy's career. I probably should have said something, and that's something I regret in my career for not doing. But those are not things you want to do when you're building spacecraft, for sure. But there's other things you do learn about that that will apply to your career later on. The part that he was working on, I'm not even sure they used it in Galileo. I ended up working on another part of Galileo. I can't even remember what it was used for. It's been so long, I'm starting to lose it.

But things like the Galileo, one of the big controversies it had is the plutonium. It had to have a plutonium generator on it. And there was a big legal court case where people that were concerned about plutonium coming back into the atmosphere of Earth, rightly so, didn't believe, you know, the statistics weren't such that you could not worry about an accident like that happening. And that's why it's important to have balances and checks, because it's true. Somebody could make a mistake, and you could have a very dangerous radioactive element that could kill a lot of people coming back into the atmosphere. But fortunately, you know, what they decided to do is use Earth's gravity and other planets to swing it around. They still did launch it, but I think it was a smaller reactor, if I remember. But that was something,

that's a critical thing that can affect, you know affect people's lives, even though you're sending it to another planet. So it's important. And I forgot your question. I kind of went off on a tangent. I apologize. No, no. I mean, we've all seen the rockets blow up throughout all of our space history. Challenger.

Yeah. And so, of course, it would be a consideration if something has plutonium in it. But my question was, what kind of design considerations do you have working in unprotected space? Or that was going to be my question. Oh, yeah. Well, definitely radiation. In the semiconductor industry, we used to joke around alpha particles. And I think in this embedded conference, I forgot the guy's name that was doing the talk, but he was talking about parts of memory,

you know, having to reboot. And one of the big things you have to worry about in memories is alpha particles, which are, I believe they're helium ions, if I remember my physics enough. That will go in and disturb a cell real easily. So you can disturb memory if you don't protect it. And even though you're testing on Earth, that's a terrible way to start a sentence. But when you're testing memory circuits on Earth, you still have to consider that because even though it's a remote probability that you're going to have a disturbance in testing, if you do have failures, it's something you have to consider because we still have radiation entering the atmosphere. Although, thank God it's not damaging enough to affect us every day. But when you send something like that into space, how do you protect it? How much shielding do you put? Can you put, well, let me just digress again back a little bit, because this will explain it. I worked on the Centaur rocket at General Dynamics,

and I learned an important lesson when one of the technicians was taking me through their factory. I went out to reach to touch the shell of one of the Centaur second stage rockets they were building, and he grabbed me and pulled me back really quick. And I said, why did you do that? And he said, well, think about what you're about to do. He said, the shell on that rocket is thinner than a dime. You could puncture that rocket. So I could have been responsible for losing $100 million for the company because I was stupid.

But fortunately, I had somebody that knew better than I was. I was the younger, and he was the older. And he taught me an important lesson that day until I remember to this day. Well, today, when you're building a spacecraft that goes to another planet, memory certainly is important. The processor, how do you protect the electronics? How do you balance the weight to value? Redundancy will do one thing, but space is a pretty unforgiving environment. So I'm not an expert in that aspect of it, but I do think about stuff like that even on Earth.

I know I've put a few random bugs down to alpha particles. Who hasn't? Well, I guess I, no, mine were more gamma. No, I'm kidding. If I could, I better stop there. I get myself into trouble. You've gotten to touch some interesting silicon. You mentioned TI's 74HC series. You mentioned to me National Semiconductor's 4-bit microcontroller and an 8051. Which of those was your favorite? You know, I'm thinking it was a match between the 4-bit and the 8051. They have different aspects.

They both used what's called a PLA, programmable logic array, which is not an FPGA. It was the precursor. So they were hard-coded logic. And I learned how to make state machines and stuff like that in a 4-bit. I also learned the process. I learned how a machine like that works. But the 8051 was the same thing, but it was a little bit more important and used in a lot of different situations. So they're very same.

Yeah. used in a lot of different situations. So they're very same. We're probably typing on one, the 8048 and some of these keyboards, but which is a derivative. But I mean, they both have that similar, they're both Von Neumann machines. The arms that we're working on are totally different. And by the way, my boss, when I was working for at Signetics, first introduced me to the concept of reduced instruction set. And I thought it was really cool. The guy, David Patterson and Hennessy, who were the, pretty much, they're not the founders. I think it came before them, but they were the ones that drove it. We have a lot to be thankful for what they did, you know, for the industry, the embedded.

Because of risk or? Because of, well, because of what it did, low power that, I mean, the microcontrollers we have today, if we had 8051s today, we, I mean, we do in various forms, but it's so much more powerful in speed and power. At the conference, do you remember Miro Samek? Oh, yeah. We've had him on the show before. Have you ever delved into his technology at all? Do you understand what he does? The UML state machine focus? Well, it's more important. It's state machines.

But what he does with state machines, I don't think a lot of people do appreciate, but I don't think people realize how powerful it is. Miro is a genius. I can't discuss why I know what I do, but I've worked with some of his stuff and I've seen some of the things you can do. And I'm thinking in terms of low power, you know, systems, silicon labs, for example, will advertise microcontrollers that'll stay powered up for 10 years. I think with Miro's technology, they could extend it a lot further. And so I'm a big fan of his, if you can't tell. The guy is, when I saw his website and the state machines, I fell in love with the technology. I haven't written anything myself, at least not on my own time. So yeah, I have to say,

I'm speaking out of the side of my mouth, but I do know that his stuff is very powerful, and I would encourage anybody that is doing low power to look at it, because you learn quite a bit from it. But anyway, there I go off on a tangent again. That's why we're here. It's all tangents all the time. It is. No hypotenuses at all. the best analogies I've ever heard. Things like, paint it white, shine it bright, hope to hell it works right. Now, that's when you're getting tired of being at a company because you see things done wrong incorrectly a lot of times. Another one of his was, ignorance should be painful. And that's a truism. It should be. It should be a lot more painful than it is.

Yeah. You learn a lot, you know, a lot of, like I say, war stories. But I think when you look back, summarize my career, I guess. I've had a great career. I've had more opportunity in my life. Sometimes I worked in a national lab as part of my, my career and I really enjoyed that, but I felt that I've worked at more in the jobs that I have than most of the people that I was surrounded because a lot of people will go to a company and they'll

be with them forever. And that used to be the paradigm in the forties and fifties. And it's still good. You want to be loyal to any company working're working for because they're paying you. They don't have a requirement. Well, you have to be paid for what you do, but they don't owe you anything. Today, though, they can lay you off in a day or a week, and so you have to be cognizant of, are you a value to a company? Are you

producing what you say you are? Are you giving the stockholders what they need? But as a consequence of that, I always learn, don't be afraid to move on to new stuff. It's never the end of the world. Keep striving for that next career is kind of the way I look at it. Do you think that that has changed some? When I started at HP 25 years ago or more, it was supposed to be a company you retired at. And this was HP before it was Compaq, before it split with Agilent, when HP had a DNA lab and when HP labs was doing amazing, weird things. And they sent me to conferences. My manager always had things that I was supposed to be learning.

And I talked to general managers occasionally, you know, it was an exciting thing. But now, it doesn't seem like people get as many opportunities at companies anymore. It can be because you don't create those opportunities. And I'm not saying in your case, but sometimes the people that make the difference between those that move on and make a huge difference are people that don't say, well, I'm just going to do this. And, you know, I hate this adage, but the old battery stamp, you know, somebody working in a factory for their entire life. You have to be always thinking about the next possibility. HP, I mean, it started in the garage, for goodness sakes. And look at where it got. They actually had a huge disk drive design. I worked with them,

and I got to see that part of it. But HP grew beyond. I have to say they grew beyond too big. They had a policy of when they got to 2, 2000 employees at one campus, they split the campus even in the same town or city. And the problem was, I think, in fighting and politics at the end between the stockholders and Dave Hewlett and Packard. I think, you know, I don't know what part Kali Fiora had in it. I certainly wouldn't judge it because I you know, I don't know what part Califiora had in it. I certainly wouldn't judge it because I, you know, that was more political than anything. But there were some nasty things going on. And I think infighting in the company had a lot to do with it. HP was a great, great company. Their calculators, their printers. I worked on numerous HP

computers early on. And I was really heartbroken that they went the way they did and became Compaq because Compaq doesn't exist. HP still survives, but they're making printers, and I forget what else they're doing now. Computers. Do they still make computers? Yeah, they still make desktops. Yeah, but you don't hear about that. You hear about Dells and Apple now, so I don't hear about that. You hear about Dells and Apple now. So, I don't know.

I mean, most of the companies I work for, Cignetics doesn't exist. Phillips doesn't exist, at least not in semiconductors. It's now called NXP. What was the first one? TI exists, but TI is, I think TI is surviving. Thank God. They're a great company. But National Semiconductor, they don't exist anymore. They're analog devices.

Is that right? I forget who acquired them. I think it was analog devices. No, TI did. I know. It's so confusing sometimes. And then you look at these data sheets, and they say, well, I mean, they still say Atmel for all of the Atmel parts. And I'm just like, I wish it was Atmel and not Microchip.

I've always been a fan of Atmel. ARM is by far, in my opinion, is the bigger of the two between MIPS. Certainly not. ARM is definitely winning. Well, it used to be every router had MIPS in it, and here comes ARM. We've done a lot of MIPS at Cisco. I studied ARM so much, I made a mind map out of them all the way from the beginning. I have this mind map of the history of ARM, and it's amazing.

I did this with atomic physics, by the way, of all the history of all, and it's amazing. You know, I did this with atomic physics, by the way, of all the history of all the scientists and stuff. A mind map will really help you. It's a really good way to figure it, sort things out. But I still thought the DSPIC was cool. It was pretty much like the analog devices 2100 family, I thought. So anyway. Is that the Shark family?

They did the Shark, but it wasn't that. The 21,000, I believe, was the Shark. The 2100, the 2101, 2105, I think. I started playing with those for a while. But those were the architecture that was all pretty much... By the way, Intel, I think, pretty much did the first DSP. I don't think a lot of people know about, I forgot what it was called, the 2700. I sent an email internally to Intel to ask, the guy that designed it was still there, and I sent him an email asking him about it. I was hoping to strike up a conversation, but he wasn't too friendly. That was sad, because there's a lot of good history in it, why they did what they did. Okay, so before we go, you've mentioned

conferences, and I know that the recent Embedded Online Conference, you must have paid for yourself, but you've mentioned other ones. Do you usually pay out of your own pocket or do your company send you? A combination of books and conferences are the same. A lot of times your boss will not pay for something and I just say, you know what, I'm going to pay for it out of my pocket. I've been fortunate like being able to go to the MSDN conferences and the companies have paid for it. But there's a lot of other conferences, online, offline videos and DVDs. If I need something, I'll pay for it. I'll find a way. It's too important to learn something.

So, you know, you shouldn't let your boss tell you what you can and can't know. Dave, do you have any thoughts you'd like to leave us with? Be nice to people. You know, that's true. Treat people the way you want to be treated and they'll respond kindly.

Our guest has been Dave Kummer, recently retired, but still learning. Thanks, Dave. You bet. Great talking to you. Thank you to Christopher for producing and co-hosting. Thank you to our Patreon listener Slack group

for questions, all of which I didn't accredit properly. So thank you. Sorry. And thank you for listening. You can always contact us at show at Embedded FM or at the contact link on Embedded FM. And now a quote to leave you with from Norman Rockwell of all people. The secret to so many artists living so long is that every painting is a new adventure. So you see, they're always looking ahead to something new and exciting. The secret is not to look back.