Earth Notes: On Being a Hardware Developer (2021)

Updated 2024-05-01 10:30 GMT.
By Damon Hart-Davis.
What does it mean to be a hardware developer? #podcast #hardware
743s "20210730 GTKN hardware designer" (captions) Uploaded . Downloads:



Hi, I'm Damon Hart-Davis and welcome to Earth Notes podcast on all things eco and green and efficient at home.

Codebar asked me to talk for a few minutes on what it's like to be a hardware developer for their "Get to know a ..." series, how I got here, the skills needed, etc. Codebar says: We want to expose our community to the huge variety of roles possible that involve coding, not just Web Developer or Software Engineer.


  • For these purposes I regard hardware as 'electronics', and maybe anything else required to interact with the physical world.
  • I'm not officially an engineer. I work with colleagues who have engineering degrees and they know things that I would really like to!
  • My skills are largely self-taught, though I do have artificial intelligence and computing degrees.
  • I got started on (very simple) hardware first as a kid, but I do a lot of software too. Often the two are intimately connected. Many hardware devs will spend much less time on software, and there's whole areas that I barely even touch such as analogue.

Here is the main body of my talk...

1988 Scamp video frame capture from Wogan BBC



How did I get into it? This is the kind of checking the privilege at the door. I'm white and middle class and so on.


I have all sorts of advantages there, but I didn't only think about electronics when I was thinking of going to university or something.


My dad got me hooked with some really quite simple bulbs and battery circuits, bizarre,


where I worked out if you open the switch the light went off except in one case it went dim and I still never worked out what that was about.


But then later there were some of these 101 electronics kits with a little cardboard,


a big sheet of cardboard with spring clips and individual components.


That really got me hooked on electronics, building my own circuits and soldering them up with a soldering iron.


Also etching my own PCBs but never tell my mum about the hole I scorched in my brand new carpet with the etching chemicals.


How she doesn't know? I didn't know. I don't know. Anyway.


And then late 70s, so I'm an old geezer as you'll see from my beard in a minute when I have video,


got to play with computers and the advantage of those is every time you wanted to make a change you didn't have to order new components by mail order and wait a couple of weeks and spend your pocket money.


So I kind of got deflected a little bit into software, but really I've always been interested in everything.


Yes, I do write my own Web pages too, but all the way down to making electronics that interacts with computing gear in most cases,


not always, but mostly that interacts with computer gear.


So being a hardware developer, I would say if you purely do electronics, you're probably called a hardware engineer.


I like to do stuff which is right at the boundary where I'm designing the circuits and squeezing every possible ounce of value out of them with some code as well.


So right. Can everyone see my second slide here?


OK, so this is just some pretty pictures. So the little robot on the left my job before uni, we were working with the two biggest toy manufacturers in the world who may still be the two biggest toy manufacturers,


Tomy of Japan and Milton Bradley in the US.


So we built this little robot, this autonomous robot, which is scoot around and interact with you and you could you could stroke it and you could talk to it and it would flush its eyes at you,


and stuff. And if you go and search in YouTube for Wogan Scamp, I think you'll bring up the little video with this in Wogan.


It's another relic of the 80s. But I've done all sorts of things.


So the current stuff I'm working on, I'll show you later on my videos.


The thing with the five on it is a smart radiator valve that I've designed, which saves up to 30 percent of your heating energy use and doesn't require you to program it or anything.


It's not fancy. It doesn't have an app. And below it, below that one, the thing with the strip board on and the coloured wires is an early prototype for it that was hand soldered.


And then just off to the right is a schematic diagram of a thing I still use, but in a slightly different way.


I power my Web servers and stuff. I used to run an Internet service provider, an early one in the UK, and I had racks and racks of machines.


And then when I had my second child, I had to give up my office and all those computers.


And so I've started running all my servers off grid and this little circuit when I then had a laptop that was doing the work of all my servers to switch it between mains power and off grid power.


So quite a few different things.


So, yeah, I was slightly distracted for a bit. Scamp there was before and during uni. So that's all the way back in the 80s.


That used the same chip as the Spectrum 48K and so if any one of you remember that as it's a Z80/Z80A.


Done. I've shown you the the radiator valve, which has been all this century as it were.


But I got distracted in between, even though I never stopped tinkering. So what did I get distracted with?


Well, AI and computing degrees. So I actually have no formal electronics training at all.


And came along. I were discussing earlier is important to know that you don't have to spend thousands of money and years and years of time on fancy degrees or courses to get the skills.


I don't have any formal electronics at all. No one has ever argued with any of my electronics designs.


So, you know, there is lots of material online and and you can do stuff yourself if you've got a soldering iron or a breadboard or whatever.


So what else did I do skills in? I found the skills you learn when you're doing low level electronics like this that talks to computing.


Really helpful in all sorts of other areas that I worked in. So I helped design a battleship.


It's still the type 23 forget that there's still a few of them around, which it was I looking after identification friend or foe created one of the UK's first Internet service providers and its first Europe's first virtual credit card.


And I worked in finance for a couple of clients, amongst others who you might remember, call Lehman Brothers and Royal Bank of Scotland.


So, you know, just slight destruction in the in the middle.


So what does a hardware developer or hardware engineer role have?


Well, you could just design the electronics and and there are certainly people who do that.


One of the wonderful experience I had doing that scamp robot in the 80s was working with Tomi and they had magnificent electronics engineering department.


I mean, it was great. So I would sketch up a design.


I remember doing a hand clap detector, which did you doing that as a little bit of discrete electronics with some op amps and stuff.


Don't worry if none of this means anything to you.


Faxed the diagram, the circuit diagram over to them in Japan.


Someone must have picked it up straight away.


And basically, sort of 24 or 40 hours later, by FedEx came back a finished circuit board with a working circuit with corrections.


I mean, amazing right now these days you can achieve the same thing without having the biggest company of its type in the world via all sorts of other routes.


But, you know, you can do discrete electronics, but generally it's also writing code to talk to it in C or C plus plus.


And these days, if you're lucky, it'll be something like Rust, but it might also be assembler market.


Java might be all sorts of things.


And it is useful to code all the way up to an application or HTML or CSS or JavaScript,


because sometimes you need to make sure the interaction with a human being is right,


even if you're not the best Web designer or whatever on the planet.


Being able to get something rough and ready working is handy.


These skills all the way up the pile are really handy.


So all of these skills, in fact, no one's ever formally taught me HTML either.


But if you go and look at any of my Web sites, you'll see I've written hundreds and hundreds,


thousands, depending on how you counted millions of pages full of HTML as well.


So none of my formal skills are the ones that I've paid to learn at university.


And, you know, there is so much stuff online as long as you can be disciplined and learn stuff and the working on your own without supervision is another useful skill these days,


given we're doing more working from home.


You can be up there with anyone else.


Just a little word on schematics.


I don't know how well this one comes across on your screen, but don't try and read too much of the detail.


If you're doing electronics, so if you're writing code, you will have screens full of lines of text, possibly coloured these days,


so you can see what each bit of your text does.


If you're doing electronics, you end up drawing diagrams like this usually sketched out on pieces of paper badly and then eventually turned into diagrams on screen.


Now, I'll show you later when I come off this slide pack.


I'll show you what that corresponds to.


But basically, this is a simpler prototype of the radiator valve.


So the big blob in the middle is the microcontroller, which has the program inside it and very clever bit of electronics.


Then all the little boxes around it are peripherals.


How I turn on the light on the top of the device or how I sense light levels in the room or how I am measuring temperature or the top right hand corner is a radio, for example.


So I can send and receive radio.


So you will get to write, you will get to do schematics.


Again, the stuff to create this diagram was, again, all free.


This, I can't remember what package we used.


This was Eagle, which probably isn't free now, but there are plenty of alternatives.


So I'm a cheapskate.


I pay almost nothing for my tools and I'm using them all legitimately.


So some good and bad points about being a hardware developer.


The first thing is, I think everyone will tell you, and I think it's been true for goodness, all the time I've been working 30 years or so, that an equivalently skilled hardware person may get paid less than the equivalent of their software buddy.


True and not true, maybe, but just watch out for that.


You can be, there is an inclination to underpay people who do electronics because everyone thinks that software people are the rock stars.


But bullet point number one here is, hey, it's all very well stirring up another Facebook or whatever.


But ultimately, it's the hardware people who make it interact with the real world, make your smartphone smart, that can turn lights on and off, open doors, turn on,


radiator valves, open water and let them through dams and stuff.


So just remember that if you do hardware, you're the people who really interact with that real world and everything else is just a passing fad, right?


And I find the bridge between software and hardware really fascinating, squeezing out every last drop of value from the hardware.


Hardware is hard. Manufacturing is slow and expensive.


For example, if I want to do another manufacturing run of my radiator valves right now, I'd have to stump up a minimum of probably £100,000.


Whereas you can knock out another software release without any minimum cost.


There's more on my "Earth Notes" Web site at Earth.Org.UK.

Show Notes

While the talk was being done live from my holiday B&B over Zoom, I locally recorded with my Zoom H1n too, which you hear above.

Maybe I do have a formal electronics qualification: an OA level (half-way between O-level and A-level at the time).

How I got Started

OpenTRV prototype 20130220 V0p09 PICAXE 18M2 microcontroller DS18B20 temperature sensor DS1306 RTC RFM22B radio LDR USB powered on stripboard front closeup 11 DHD OpenTRV TRV1 containing REV7 20190421 7 DHD OpenTRV REV10 data relay with SIM900 GSM shield 20190421 8 DHD

My dad got me started maybe age 5 or 6, I'm not sure, showing me how to build circuits with batteries and bulbs and switches.

I graduated via 100-in-1 electronics kits with spring clips, to drawing up my own circuits and buying the components from the likes of Watford Eletronics and Maplin by mail order, and soldering them up on strip-board.

But dreams are big, pocket money small, and my soldering slow. So when a school and home computer became available in the late '70s, I was deflected to the dark side (software), though still pretty low level, often with machine code mixed in, sometimes laboriously typed up on a real manual typewriter, with hand corrections in pen or pencil!

Before going to university I got a job with a start-up called Personal Robots, and amongst other things we developed from scratch a toy robot along with the world's biggest toy companies in the US and Japan. An Arduino Uno has similar computing power but much more memory than that design of mine then, and the tools were cranky enough that I ended sending an angry telex (heard of them?) to a certain Bill Gates! The toolset was C (still fairly new) and assemblers running from floppies on a BBC Micro Z80 second processor, taking longer than all lunchtime to build. Code than had to be programmed on to a UV-erased EPROM chip and put into a socket on the robot's board. We could pass run-time messages between the robot and a desktop PC or two via a very simple network over serial cables running at somewhere round 1kByte per second. That part felt in may ways the same as current 'IoT', but everything was far more expensive and drew maybe 100x the power of today's equivalent!

Have a look at this video clip of our robot "Scamp" appearing on the BBC's prime-time talk show in 1988, Wogan.

The Web as we know it now was not even a twinkle in anyone's eye then. So everything I started with is at the bottom of a typical stack today!

After university I did a bunch of now-unfashionable work, such as part of the design of a UK warship (the Type 23 frigate), IT support for oil exploration (for BP), creating one of the first UK Internet Service Providers (ExNet), and investment banking including a certain Lehman Brothers... There have been a couple more start-ups of my own in there too.

~2726 words.