A hard-fought lesson about USB cables

That Hurts my bran.

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My engineer brain cringes at the wiring job on that USB to USB adapter that the poor author had to make to solve his camera problem. The USB data pair, like any balanced differential signal pair, likes to be twisted for reduced noise pickup. I suppose it will work as it’s only an inch of wires.

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Working for a manufacturer that makes products with both USB A and USB B cable connections, different purposes for each, I have been learning the hardway about the differences in the cables. I agree that having a charging only cable can be advantageous at times. However not having the cables labeled as all pins wired/some pins wired is a difficult issue.

It reminds me of the old days when Category 5 cable at 10Mb/s would only use two pairs of wire so to save costs manufacturers would sell a four conductor cable. It worked great for low speed connections at 10BaseT but not so well at 100BaseT. The important thing is the labeling.

There was of course the issue of the poor design choice on the camera itself but that is a different topic.

If a product comes with a USB charger, why would the company spend more money on a cable the product doesnt need?

And how large is the data only usb cable market? Sure, some people want them, but I would guess the general consumer barely knows this is even a problem.

Well, ideally, the data pins aren’t optional. They are used to negotiate how much power the device needs and how much the outlet can supply. But lots of times things will charge/be charged without them.

I like to do this as well. Im surprised the more consumer minded product lines dont incorporate this small but welcome feature. When the patent for Apple’s over engineered, reversible usb hit the news, I just laughed.

As for a touch solution… my favorite cable Is like this one. My hands know what to do every time.

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Which is great for unique battery situations or universal chargers, but for most manufacturers it is just extra cost. Not only are they saving on copper, but they are likely also skipping the tech in both the device and the charger. Again, I have a really difficult time believing data only cables are designed for consumer demand, and not for cost.

Protip: that’s not “upside down” any more - it’s the standard for Android phones now… I’m not sure why but my guess is that inadvertent cord-yanks have less potential to damage the port. I have that HTC One M7 (not in sexy black, though) and every android phone I’ve seen since then (early 2013) has had the port that way.

Also, wouldn’t it be trivial for the manufacturer to add a bluetooth 4 chip to that and stream the video wirelessly? I, personally, am an old-school curmudgeon that likes cables because you can’t beat copper but when you’re making something that is designed to work with various phones you are bound to come up against this issue eventually.

PS: I want one of these http://www.amazon.com/PowerUp-Smartphone-Controlled-Paper-Airplane/dp/B00N8GWZ4M/ref=pd_sim_hi_3?ie=UTF8&refRID=14ERXFDZYPDTZKB4SP8Q

Yeah, it work hardens and then cracks.

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If you own the thing you’re charging from it’s fine but if you’re plugging into a mystery USB port on a mystery machine, non-data cables are a pretty good idea. I agree that few people realise this, though.

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Please don’t cringe, just please teach us. Now I know and I doubt I would have if you didn’t mention it. I will go and learn about twisting these data pairs if it ever comes up in a project. Unknown unknown replaced with a known unknown.

I jealously hoard Blackberry chargers, as they seem to work better than any of the others.

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In general, any differential signal pair (something+/something-) strongly benefits from twisting the wire pair, or, if on a circuitboard, at least having them laid closely parallel.

How much can you stray away from this rule will depend on the specific signal, the drivers, the line properties…; any deviation (and even none at all) will distort the signal somewhat. If the distortion goes above what the receiver can handle (see eye diagram), you have to go back and change some variables. It’s better to hold to the best practices even when not strictly needed as this gives you a further margin where you can abuse the system if needed.

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I hoard all chargers. People throw them out just because a chewed cable or upgraded phone, and they are still a perfectly good PSU module when extracted from the box. One of them runs on an experimental power plant (now temporarily (hopefully) decommissioned) and feeds a RS485-Ethernet converter hacked into the grid tie inverter box.

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Just noting a typo - UBS instead of USB.

It would be nice if wehatever replaces USB is built to a single standard uniform specification. Or at least if there are variations in what it does there aren’t many and they are clearly marked.

I lost my ps3 controller mini-usb cable and now have to unplug an external hard drive if I want to charge it up because it’s literally the only mini USB cable I have that will also charge it, all the others seems to be charge only or something and just don’t work with it. I thought it had broken originally.

And that’s why so many of my toys have the mini one replaced with the micro one. (You cannot do it directly, the micro is shorter than the mini; otherwise they are pin-compatible. Solder the casing to the board, then use thin copper strands to connect the pads with the pins.)

The one nice thing about USB being a ubiquitous lowest-common-denominator standard is that, while that spawns a zillion painfully half-assed implementations(like the entire mess that is USB OTG), it also puts some pressure on designers of USB silicon to keep in mind that expensive customer whining will be minimized if their products can cope with severely deficient cabling, shoddy peripheral design, and other real-world factors.

It can’t be relied on(as with most things USB) but it is quite common to see USB devices working away merrily, without the slightest apparent concern, on cables that are over-length, improperly shielded, damaged, untwisted, and sometimes several of these at once. Not good practice; but the world is held together by lousy hacks and duct tape more often than not.

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Not an issue for the iPhone since the lightning connector is reversible.

It’s also too bad they didn’t opt to add a second USB/lightning connector on the reverse side. That would have solved the issue for Android phones, plus allowed for plugged-in use of the device.

That said – I have one of these for my iPhone, and I dearly wish I could get a cable for it. It’s way more awkward to use than I anticipated.

1, it’s in an awkward location to hold the camera and use the app to view it.

2, having even a short cable would make it a heck of a lot more flexible.

It would be handy for things like checking under a sink or inside a wall, which currently require either using the video mode, recording, blindly flailing the phone around, then watching the video (or contorting into positions better suited to someone for whom yoga is actually an enjoyable activity); or my most recent task, seeing if the cat we’ve been saddled with for 2 months is hiding under the bed or in the closet to ensure I don’t lock it in the room and return to find evidence of its displeasure on top of the bed again. (Regular camera doesn’t work without moving some under-bed storage units, thermal camera pretty much sees right through them).

Maybe there is some kind of lightning extension cable that would work, but I haven’t found one so far.

edit: After posting this, I thought… “Well, I haven’t looked lately…” and opened up Google. And then Amazon. Several options. Sadly, nothing cheap, but it’s probably worth that $20-30 to me since I could use it to extend my charging cable when I need to, too.

Fake Science has a great Lifehack for dealing with cables:

To make this post useful, here are some folks who are sussing out the lightning connector:
Reverse Engineering Apple’s Lightning Connector | Hackaday

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