Get Over Your Fears

Some projects are just too complex, that’s for sure. But I’d be willing to bet that some things you think are too difficult actually aren’t, and it may be that all you need to get over your personal hurdle is a good demonstration. Here come three cases in point.

I was looking at the new Raspberry Pi Compute Module last weekend. They have a whole bunch of high-speed traces: things like Gigabit Ethernet, HDMI, and those crazy-fast SDI serial camera interfaces. I have no experience in high-speed design and layout at all, and frankly it gives me the willies. But the Raspberries also shipped me an IO demo board, and concomitant KiCAD design files, with the review board. Looking at it, they were just wires — maybe pairwise length-matched and impedance controlled — but also just wires. Opening up the KiCAD board file and clicking on the traces just like I do with my own designs, I’m a lot less scared. That was a revelation for me.

In a great writeup of his experience building ten different Linux single-board-computers from scratch, Jay Carlson had a similar effect on me. I would never have considered breaking out the hotplate for some CPU-and-DRAM action, and I’ve never had to lay out a PCB with a high density BGA chip before either. I’m not quite into Dunning-Kruger territory yet; I still have a healthy respect for the layout intricacies in fanning out a tight BGA CPU into a DRAM. But Jay’s frank assessments of what is easy and what is hard make it all seem within the realm of the doable.

As Mike and I were talking on the podcast about Jay’s work, Mike came clean about his fear of BGAs. I’ve done enough reflow-plate soldering, with parts that have a lead pitch that’s a factor of two finer than the 0.8 mm pitch BGAs in question, so it doesn’t seem implausible to me. And I’m 100% sure Mike could pull it off too, but he is in need of a BGA guru. Any good hobbyist videos out there?

Being a nerdy type, I’m much more focused on the knowledge and the inspiration, but maybe the courage is equally important — at least I think I undervalue it. I don’t need to lay out HDMI lines, or build a from-scratch Linux box, but I am no longer afraid that I couldn’t, and that’s because I’ve seen detailed examples of fellow hackers who’ve done the same. I might not get it right on the first shot, but I’m not afraid to try, and I wouldn’t have said the same before looking over other folks’ shoulders. Forza e corragio!

23 thoughts on “Get Over Your Fears

  1. Shameless plug here: I’m just now finishing a project (freely available) that allows the end user of a RasPi project to easily configure the system.

    If you have a product that includes a Raspberry Pi, you can use this software and include a pushbutton on the device for configuration.

    When pressed, the system will stop it’s application and put up an access point with the same name as the system name. When the user connects to the AP they’re presented with a configuration panel that lets them enter the wifi and password to use, and a handful of other configuration options. Disconnect and the system goes back to running your application.

    The project is currently working, should be complete in less than a week. (I only need to slog through some HTML to get things to look nice.) Also, it’s well laid out and labelled so it should be easy to modify for your individual needs.

    So if you have a *product* that includes a raspberry pi and needs the end-user to select the wifi or choose other config options, this should be a drop-in solution for you.

    Check my .io page for the “AppDaemon” project. It’s already up on github, but under construction for the next couple of days.

  2. Exactly, don’t let fear keep you from jumping into a project. What’s the worst that can happen, it doesn’t work when you power it on? You can learn from that, too.

    Unless it’s high voltage, caustic chemicals, or radiation. Then a healthy dose of fear is a good thing. :P

    1. When fear does strike, it is not so much fear of physical harm, but fear of investing days (weeks …) of work and then having a dud. Been there and done that. Yes it can be a learning experience and a stepping stone. Sometimes you can sense that the risk is high and you aren’t sure if you want to go down that road again.

      1. I think with our modern endeavours we’ve all forgotten a bit the purpose of fear… Fear is not there to tell you to not do something; it is there to remind you to be careful/cautious as you move forward!

    1. For me at least time and money play a part.
      But the fear or put in reverse the achiveablity of a project is what gets a project selected. Don’t want to waste my money and time on a project I can’t hope to finish (which is of course often the fear talking as any project can be finished eventually, it just might cost more time and money every time you make the miss-step or have to rethink). I would think we all do that avoidance of a project we think is too challenging for us – at least right now and take on something else instead.

  3. I think it is an astute observation that dealing with fear is a significant issue. Being able to deal with that is a bit part of what makes a hacker a hacker. Keep pushing the limits further out, that is the thing.

    Also time is a finite resource (and energy). Nobody has the time and energy to tackle every thing that is interesting, so choices need to be made and things need to be prioritized. I never plan to lay out an ARM board that could run linux. I can buy those — but that is my choice of where I want to direct my resources. There is nothing wrong with those who decide to do such a thing. One of these days though, I do plan to learn enough KiCAD to lay out some simple boards.

  4. Luis Rossman on YT. I just about fell off my chair (along with a few less-mentionable things) when, at the beginning of a rant video about how Apple puts 5400RPM platter drives in their then-current preconfigured iMacs (this was a year or so ago… FTR, for those who have fallen to the Dark Side, and actually *want* something from That Fruit Company, I had a Toshiba Satellite in my first year of college, 2004-2005 or so, that had a 5400RPM drive and a Willamette P4. It was *awful*…) he just casually hand-soldered a 12pin BGA with a lake of flux and a rather coarsely-tipped solder station.

    I didn’t know that was even possible.

    1. Inexperienced solderers always think fine pitch parts require a fine iron tip, which makes intuitive sense but it utterly wrong.

      Soldering is always more about understanding and manipulating the physical properties of solder than it is about precision. A fine tip can’t put enough heat into most joints which just sets you up for failure, but having enough heat and enough flux and the right amount of solder and even if you’ve got a soldering iron the size of the moon a good joint is almost inevitable. Surface tension does 99% of the work.

      1. Exactly – the smaller tips are superb in some situations, but that is about access or heating only the target part on dense boards. It also requires an iron with real umph and reaction times so it can overcome the lack of thermal mass at the tip.

  5. The trick to laying out any high speed lines:
    Read the datasheet and follow the recommended trace size, spacing, length, pair length matching, and termination.

    This will get you in the ball park.
    Then let the PCB manufacturer which traces need to be impedance matched (also document in the fab drawing).

    They will guide you through any tweaks you might need to trace size/pair distance to meet their process requirements.

    But in my experience, the datasheet recommend parameters are typically good enough, that the PCB manufacturer can hit the impedance tolerance by controlling the trace plating process.

    One of my buddies over at Motorola (formerly National Semiconductor), once told me:
    “Application engineers are the only REAL engineers, everyone else just follows the datasheet.” ;)

  6. This article is huge for me. I’ve been following a long time and as a straight software guy a lot of this website goes over my head. I really appreciate the fact that you’ve put this out in the open because it encourages someone like me to bite off my first project.

    1. Do it man! I am a software guy. At least I think I am, or I was one once.

      Hard to hurt yourself with a breadboard and 5 volt supplies! You may blow up some parts now and then, but I am surprised how rare that has been for me. Get power and ground right and you can thrash around after that!

      It can be a lot of fun — or else I would simply do something else.

    2. I was once in a similar position, but I’m not really a software guy either. I’m a do whatever I want and learn along the way guy. Hardware is what actually got me into software. I’m still not super at either, but I’ve made lots of projects that turned out well enough for my needs. Of course I’ve had some projects that I later realized would go nowhere until I learned a lot more about what I was trying to do, but if you just put it on a back burner and try it again later, you’ll be surprised by how much you pick up from unrelated projects along the way.

      I recommend finding something you are really motivated to do, and do it as well as you can. Starting simple isn’t something to be embarrassed about. The number of people who never even feel the desire to try is what is truly sad. Where you are and where others are is unimportant. It’s all about where you’re going.

  7. The “Dunning-Kruger territory” was well recognized and analyzed by my gunny back in the 70s. To wit

    “Too stupid to know that they are stupid”

    And his corollary: “Too many stupid people, not enough napalm”

    Per GnySgt Scott, MCAS El Toro, ca 1978

  8. I must not fear.
    Fear is the mind-killer.
    Fear is the little-death that brings total obliteration.
    I will face my fear.
    I will permit it to pass over me and through me.
    And when it has gone past I will turn the inner eye to see its path.
    Where the fear has gone there will be nothing.
    Only I will remain.

    ― Frank Herbert, Dune

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