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"I Have A Graaand Plan!" -- The 'Universal Formula' for a basic cyberdeck, Part 1 -- Parts, Variations, and Substitutes

A project log for A Cyberdeck for the Masses

Most people should be able to build and personalize this 'deck to their liking.

StarhawkStarhawk 01/23/2022 at 10:150 Comments

Sorry for the wait. One of the many phrases my grandmother had -- between her, my grandfather, and my mother, I've got a phrase for dang near everything! -- was...

"Life is what happens when you're making other plans..."

No kidding. Put differently, life's little unexpected quirks and all can be SUCH a pain in the tail. Ugh.

So. The magic formula for a simple cyberdeck.

Stick PC, like an Intel Compute Stick, or a clone or "compatible". USB 3.0 external SSD. *Powered* USB 3.0 four-port hub. eDP laptop LCD panel. Universal HDMI-to-eDP converter PCB. USB keyboard and mouse of some kind. Power supply that runs everything.

Linux Mint is your OS. You don't need to be smart to use Linux. If you had to be smart to use Linux I'd never get past the boot screen. I'm not out-and-out proof that there's a village somewhere that's short one idiot, but I'm about the modern equivalent of the caveman that hits himself with his own club because he wants to know what will happen if he does. (Spoiler, Og have bad time of it, when Og hit own head with club...) If you can use Windows XP, Windows Vista, Windows 7 at an "I know how to turn it on and get to Google" level, you will *probably* be OK in Linux with a little help once you install it. There will be a section on that!

That's really all you need, at least as far as computery stuff is concerned. I usually add a USB WiFi card because the built-in WiFi on those Compute Sticks and their clones/knockoffs ("compatibles") is universally horrendous at best. For some strange reason, sound of all things is usually a bit of a bear to work out as well, it's one of the few things that doesn't "just work".

Of course you also need decor and structure -- make it your own! There are just too many creative variations here to even begin to suggest anything, with one sole caveat that I will bring up. It is VERY common to rummage about in the attic, find some vintage relic computer, and upon applying power, discover it's dead -- and then just shrug, gut it, and put something far more modern inside.

FOR THE LOVE OF ALL THAT IS GOOD AND PLEASANT IN THE WORLD, DON'T FREAKING DO THAT!

(Please read this, but if it genuinely can't possibly apply to you ever no matter what, or you're just beyond any redemption and hope in that department -- there's a [RAMBLE OVER] label at the end of this, just scroll to that... but if I hear that you've destroyed innocent vintage computers by willingly not reading this, I will find you and I will follow you for a week with an out-of-tune thrift shop accordion in the least musical way possible.)

Instead, Google the make and model of the computer and see if you can find an enthusiasts' community around the machine. If it was a machine of any notoriety or popularity -- even if its notoriety came from poor sales and everyone kind of hating on it (like the TI-99/4A, which famously convinced Texas Instruments not to be in the computer market! -- chances are that a community of people who like the thing for its quirks has grown up around it anyways. Even if you don't want to repair it, you can almost certainly find someone to sell it to, and others who will tell you how to safely sell it and safely ship it.

A particular special note. Commodore computers, especially Commodore 64s, are NOTORIOUS for their original power bricks going sour over the years and doing awful things to the machines when you plug them in again after a few decades. They are among the easiest computers to repair afterwards, because the community around them has a fanaticism that borders on that of a religious cult (LOL) and there's just so much *of* it. I can recommend personally the Lemon64 Forums, but if you have a little electronics knowledge (all you need, really, is a soldering iron and a multimeter) and some time to kill, Adrian Black's YouTube channel, "Adrian's Digital Basement" has several so-called 'repair-a-thon' videos, and they're quite educational. Each one he fixes multiple dead vintage systems of a single kind, each with different problems. Both Mr Black and the Lemon64 folks are AWESOME.

For what it's worth, a common and easy way to tell if chips are bad, in ANY system, new or old, is to apply power and feel the tops of the chips with your fingers. It's easier to do this on older computers, the chips back then pulled way more power.

[RAMBLE OVER]

What eBay and Amazon call "MiniPCs" -- usually smaller than an Intel NUC or clone, these are more like a Roku 2XS with actual computing power inside -- or, if you can manage, a particularly low-end laptop. Anything other than a low-end, compact laptop, unfortunately, is going to have a mainboard much too large to be usable, unless you're building an absolute monster big enough to have a shoulder strap on it. I've got a Dell 11 3000-Series laptop that is giving me some issues, I'm going to try and rework it into a monster 'deck for the example build, as a bit of a flex because I can lol.

Windows-based tablets are going to be a bit hit-or-miss, a lot of them have very weird screens where you really can't use anything else, and many lack a secondary display output, which means that reuse here is nearly impossible unless you do some pretty clever stuff. IMO: don't bother.

Internal drives on "USB IDE SATA" cables are... okay... but those only really are USB2 devices, the newer ones that are SATA-to-USB3 are better for this. However, both are really only meant to be used for testing, any claims of long-term reliability by the seller or anyone in marketing, *especially* anyone without demonstrable firsthand experience, should be considered suspect at best. Also, platter drives (mechanical *hard drives* -- not SSDs, those are solid state, hence the term SSD, "soild state drives"!) are fine. Yes, they're ungodly slow next to an SSD, but they're also deplorably cheap, and most of the time you're going to be working with processors far too anemic for the difference to matter.

Also, if your system-of-choice has eMMC storage, YOU ABSOLUTELY NEED AN SSD OR MECHANICAL HARD DRIVE. Because of the way eMMC is designed and built, it is not a reliable storage solution in a long-term sense. The simple explanation is, it's a single chip with memory and a controller inside of it, like an SSD but on a single chip. However, that memory has a limited number of accesses -- reads and writes -- before it goes bad, and the memory in eMMC in particular is quite limited in that way. The point, after all, is to lower costs, so they use the cheapest stuff they can get without it almost instantly failing, so the number of reads and writes it gets is a lot lower. Most operating systems (Windows included) just don't care, and the algorithms for reading and writing that make this stuff last at least a little longer ("wear-leveling algorithms") are likewise cheap -- resulting in a very limited lifetime for these things.

Further, they are 1000% irreparable. When a platter drive dies, usually it's a bearing failure, you get that clicking sound. You actually can, under certain circumstances, take that drive apart in a laboratory clean room and move the stack of platters over to a second, essentially identical drive. The challenges there are in finding as close to an exact replacement, working drive to swap the platters into, and finding someone with the lab grade clean room who's willing to let you borrow it. An SSD? You can replace burnt controllers, and if all else fails you can pull the chips off and read them out in a $50 eBay chip programmer.

But you can't do that with eMMC, it's literally one single chip. If it dies, it's dead, there's nothing to do here, go home. I hope you have good backups. If you don't, you're screwed!

...so don't use it. Use another drive, and boot from that. Pretend the eMMC doesn't even exist, or at most, use it for your Linux bootloader (usually GRUB2). This is fine. Just don't *then* use a USB thumb stick, they're meant for storing files casually -- photos, documents, that sort of thing. An operating system needs to access its drive at a rate that will burn a USB flash drive (thumb drive, etc -- there are many alternative names) out in a matter of *days* of casual use. It will be a rapid and extremely painful death.

As for USB hubs -- obviously, USB2.0 is absolutely serviceable, just slower. In fact, it's usually only a minimal performance difference, if that, running the OS on a USB2.0 hard drive or SSD instead of a USB3.0 drive. You *absolutely* need it to be powered, though -- the USB ports on a MiniPC or a Compute Stick (or clone or knockoff) are sort of adequate, in terms of the power they can provide, for a USB wireless mouse and keyboard combo receiver and maaaybe a USB stick (you rarely get more than two or three ports on these things), but something like an external hard drive that's mechanical and uses one of those USB Y-cables for power and data (where there's a separate, extra connector for additional power) is going to choke that out and bring down the entire USB subsystem on that device. For sure, four devices plugged into a hub will do it easily.

You of course can use larger USB2.0 or USB3.0 hubs -- 7-port ones are sort of common, but far more expensive than 4-port models -- and there are (extremely shoddy, but effective) ways of converting a bus-powered hub with no external power option to accept external power. You really can't have too many USB ports, in my experience, so whatever you can get, get. That said, be aware that most cheap eBay-sourced and Amazon-sourced USB hubs from no-name sellers either internationally or that import such things domestically (which is nearly always a ripoff) use USB hub chipsets that don't work properly on anything but Windows -- on systems like this, your eg $20 10-port USB2.0 hub will only run at USB1.1 speeds. Sadly, this is because the USB chipset manufacturers haven't created decent drivers; the solution is to avoid their products. For what it's worth, I've had strangely good results from IOGear brand devices.

A brief note on keyboards and mice. Obviously, use what works for you, but just be aware that some of those options might be harder to make work than others. For instance, nearly any USB Apple keyboard will work properly with Linux (and the keys will even act as their Windows equivalents, in the locations you'd expect them to be!) but very old Apple keyboards using ADB will require a special converter -- while you can make this, easily, for a $5 or so Arduino clone and a bit of time with programming, my experience with the Arduino editor tells me that this is not as easily done as one might otherwise expect. The editor tends to get hung up in some particularly shortsighted ways, and its error reporting is... lacking, at best, in terms of friendliness to newcomers and non-programmers. Even more oddball keyboards will require something like QMK custom keyboard firmware, which is apt to be a nightmare to the unprepared and the inexperienced.

Regarding displays. There are a LOT of possibilities here! You *can*, in fact, use desktop monitors and retrofit them, but you need at least a little bit of electronics knowledge to do this easily -- basically, you remove the original power supply, replace it with your own, and since nearly all modern monitors use a backlight inverter built into that power supply, you'll need a universal inverter off eBay to replace it.

Laptop LCDs are the obvious choice, they're easy to get, they're cheap, and they are easy to interface with eg HDMI and other common display protocols. Most laptop displays nowadays use a protocol called "eDP" to connect to the laptop internals -- this is "embedded DisplayPort". If you're handy with electronics at at least a moderate level, it's actually not that hard to make a simple converter to standard DisplayPort (see https://flogbook.wordpress.com/2018/09/30/passive-displayport-to-edp-adapter/ for instructions.) *However*, be aware that DisplayPort connectors use a 20pin connector with 0.5mm pin pitch, and they're surface-mount. This makes things... hard... simply as far as soldering the connector goes. Cut cables are not really a solution here, as the design of the connector makes it nearly impossible to get a multimeter probe in there to work out which wire goes where -- and if you've ever done that sort of work before, you know just how widely wire colors can vary from standard... where there even is one.

Older displays, and some cheaper new ones (such as the one in the Dell Inspiron 11 3137 I have for the example build later in this series) use the older LVDS protocol, which is not nearly as universal -- although far more so than most folks think. A friend of mine on here, Arsenijs, has an EXCELLENT guide to dealing with this -- https://hackaday.io/project/179868-all-about-laptop-display-reuse -- but the specific layout may be a bit confusing if you don't know the lingo. Simply put, you probably want these specific entries, in this specific order --

[WIP] MT6820-B board information
How to find info on your LCD panel?
Common LVDS laptop panel pinouts
LVDS cables for controllers
Rewiring a MT6820 cable

eDP panels and their controllers, however, are pretty much just plug in the cable at both ends and go. All you need is a 12vDC power supply of at least two amps' rated current capability, and you're good to go. No futzing with cables and controllers or ordering a PCB with bespoke programming and cabling from overseas... what a mess!

However, sometimes alternative displays are kind of interesting, and sometimes not all that much of a bother. If you're doing a build that's heavily rooted in the 1980s, look at old portable TVs, especially the black-and-white ones with a CRT picture tube. These rarely need that much power -- usually about 12v 1a or so, sometimes a bit more or less (generally no more than 1.5a, however) -- and although they are relatively heavy and bulky in comparison to a sleek, slim modern LCD, they add a considerable level of period authenticity to a vintage-style system if you're going for that. Best to avoid the color ones, though -- early color CRT televisions, particularly the portable ones, had truly awful resolutions, and are far, far too blurry to use. A simple pair of converters is all that's really needed to make that work with HDMI -- most of those televisions have composite video input on a side jack. It's really not that bad!

Use an HDMI-to-VGA converter, one with a MicroUSB power connector, and then a VGA-to-Composite scan converter (these are usually listed on eBay as "VGA to RCA switch box converter adapter" devices) and you'll drive that old TV just fine. Total cost should be somewhere around $25. There *are* HDMI-to-Composite converters on there (avoid the ones that are very obviously cables with no electronics in them at all, those rely on being able to do weird obscure things and it's just not going to happen) -- I can say for sure that the "Mini" converters do NOT work, but I cannot speak to newer devices such as the ones listed as eg "1080p HDMI-compatible to AV convert cable male to 3RCA composite female adapter" etc, as I've not used them yet.

You can also use this trick to make eg some portable DVD player aux/add-on screens or "automotive backup camera" screens and DSLR monitor screens and such work as well -- but those get expensive fast. There are also prebuilt displays on Amazon for about $100 but be aware that what you're getting is a phenomenally nice housing and a surplus laptop LCD paired with an eBay-grade standard display kit that's worth maybe $25. You're certainly not getting $100 worth... if you're lucky it's about half that. I have one -- the display panel is essentially worthless and the build quality inside is truly shameful, but the housing proper is fairly thick powdercoat steel that is sturdy enough to probably be capable of stopping particularly low-caliber small-arms fire.

There are some *really* interesting displays out there, if that's your thing, that you can use if you're into that and you're fairly advanced with such things -- I've got an old Compaq Portable III that's genuinely beyond rescue, for example, but I'm going to rebuild it with a similar plasma display screen and more modern guts at some point -- but that gets into highly technical stuff and sourcing strange components from foreign countries, and it does so both remarkably easy and remarkably fast, so that's beyond the scope here.

Power supplies, by the way, need not be a thing to sweat over. I've used everything from generic eBay laptop bricks stripped of their housing and zip-tied together (literally!) to oddball such bricks -- the LaCie "Bigger Disk" brick is a favorite, it's dual voltage at 12vDC 3a and 5vDC 4.2a max output, but it uses a very strange four-pin Kycon connector for power -- those are sometimes *ahem* a bit 'fun' to get ahold of. Bottom line, if it works for your needs, however janky it may seem to others -- use it! "If it's stupid, but it works, it's really not stupid" is an axiom to remember here.

A word about batteries. By and large this is not a thing to tangle with if it's your first rgoododeo -- but if you've some experience and you're comfortable enough with your handiwork that you're willing to risk a light-metals fire in public spaces for doing it wrong -- go for it! Just be aware of what can go wrong, and how easily -- and how to deal with it. You need a Type "K" fire extinguisher ("Purple K" is the common brand) -- lithium batteries have magic flames inside them that make them work, and a standard ABC extinguisher just won't do for the kind of fiery temper those things have. Type K extinguishers are absolutely necessary -- that's what they're designed for, after all.

So, there's your ingredients and some (rather extensive!) notes on easy variations and substitutions and easy pitfalls. The next project log will give you a fairly basic idea on how to hook it all together.

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