Monday, December 20, 2021

USBefuddled

Glenn Fleishman:

USB-C was supposed to be the last cable you would ever need. It hasn’t worked out that way.

[…]

The problem is that USB-C has become a connector for distinctly different purposes and glancing at a port or cable rarely tells you enough to know what will happen when you plug in the cable. The USB-C connector is supported (but not required) by USB 3.1 and 3.2 and required by USB 4 (and Thunderbolt 3 and 4), even though until version 4 of each specification, they were distinct standards that intertwined.

Plugging in a USB-C cable can raise all sorts of questions. Will you get the maximum speed between two devices? Will you get the wattage you need to power a computer or recharge a USB battery? Will nothing happen at all, with no clue as to why? There’s often no way to know, even if the cable’s long-ago-discarded packaging actually contained all those answers, because you have to know about the ports on both ends, too.

[…]

How could the USB-IF improve on this, particularly in cooperation with Intel’s Thunderbolt group? The labeling I mocked at the outset is actually the right direction.

Previously:

Update (2022-04-19): Glenn Fleishman:

Trying to understand the modern flavors of Thunderbolt and USB? Want to know which cable to use and why you’re getting slow performance instead of gigabits per second? My new video explains it all.

lso check out my book, Take Control of Untangling Connections, a how-to and reference guide for sorting out the right ports, peripherals, cables, and standards across all mobile, laptop, and desktop hardware.

11 Comments RSS · Twitter

I keep reading about how this is such a headache, yet I've never had a problem with USBC.

The convenience of being able to use any charger outweighs the non issue of this rumor.

Kevin Schumacher

I’m not quite sure what you’re calling a rumor. The actual specifications? The lack of clear labeling on a lot of packaging, cables, and ports? The reuse of the same name and connector for umpteen different capabilities?

Just because you’ve supposedly never had an issue doesn’t mean there isn’t an actual problem here.

And that convenience will vanish the day this bites you, too, which it inevitably will.

There clearly is a problem here, but it's also obvious that this problem only applies to a small minority of users. Most people use USB to charge a phone, or to connect something like an SD card reader to their computer. Maybe they'll have an external screen with a USB connector, or something like that. They're not going to have any issues, they don't care about "maximum speeds", and they're probably not even going to notice if their phone charges a bit slower.

This is a real problem. The USB logo program is a complete clusterfuck. But at the same time, most people are never going to notice.

For me, and plenty of people I know, Apples proprietary connectors have caused plenty of problems, whilst I have never encountered anyone who has suffered from one of theses fabled USB-C complications.

Is the wattage even down to the cable? I know I've charged my MBP with a wide variety of bricks and cables, and it's always worked. Yes, sometimes the weak sauce brick won't charge particularly fast, but I've had the same issue when charging my iPad. It's not a USB-C issue.

Again, if you put all the issues I've had with USBC one one side, and then all the issues I've had with Apples various proprietary ... actually all the issues I've had with ANY USB standard on one side and all the issues caused by Apples connectors (mostly running around asking people if they happen to have that special connector I need for this specific "i" product) then the Apple side absolutely crushes it.

> whilst I have never encountered anyone who has suffered from one of theses fabled USB-C complications.

*Waves* Hello, right here! I don't know if a comment thread over the internet counts as an encounter, but here I am.

I have an unlabeled USB-C cable sitting on my desk right now. I don't know if it's any of the earlier three versions of USB 3.2, be it 5 mbps or 10 mbps. Or if it's Thunderbolt 3. I think I can rule out USB 3.2 Gen 2x2 because it's probably too old for that, but I'm not sure. Also, I'm not sure if it's USB 2! Because some USB-C charging cables, including all of Apple's charging cables, are actually just USB 2 cables.

However, if I use it to connect any of my USB devices to my computer, it appears to work. But I can't easily tell if I'm getting the full bandwidth and charging capabilities of the device that I've connected using it! There's no easy way to find out, other than doing extensive and laborious testing by comparing it with a cable whose specs are known. I've yet to do that though because I have better things to do with my time! So I generally just don't use this cable if I can avoid it. Either way, it's a waste of resources. I should just be able to know what I can do with this cable by looking at it, full stop.

I can at least say that plugging in a few (though not all) of my Thunderbolt 3 devices does *not* work with this cable, so I think I can rule it out being a Thunderbolt 3 cable.

But with USB 4 and Thunderbolt 4 now out, that means that before long every USB-C cable I own is going to be one of SEVEN (!!!) possible cables:

USB 2

USB 3.2 Gen 1x1 (aka USB 3.1 Gen 1, aka USB 3... as though these ever changing damnable names aren't confusing enough already)

USB 3.2 Gen 1x2

USB 3.2 Gen 2x1 (aka USB 3.1 Gen 2)

USB 3.2 Gen 2x2

USB 4

Thunderbolt 3

Thunderbolt 4

Now granted, USB 4 and Thunderbolt 3 *may* use the same cable, or at the very least be equivalent so that either one fully works with the other. But I'm not 100% sure, and I haven't found a clear answer anywhere because I don't think anyone actually knows at this point.

This is a god damned horrible mess. I'm a lifelong programmer and very technically minded, and I can't bloody well figure this out or how to deal with it. That means that non technical folk have little to no chance. Imagine what'll happen when someone plugs in a USB 4 drive with their Apple USB-C charging cable and wonders why it takes so long to copy a few movies or make a backup. The box for the drive said it was super fast! And the cable fits, which means it should work... right?

Let's hope that the organizations in charge of USB and Thunderbolt decides that, in order to be fully compliant and certified, all cables *and* sockets must be clearly and unambiguously labeled for their capabilities. This already happens often, but not even close to consistently. Granted that won't help everyone because lots of people ignore those little icons and just focus on whether the cable fits in the plug, but at least it would help me and people like me, and it'd be a start!

Correction: with USB 4 and Thunderbolt 4 out, every USB C cable is one of at least TEN!!! cables:

USB 2

USB 3.2 Gen 1x1 (aka USB 3.1 Gen 1, aka USB 3)

USB 3.2 Gen 1x2

USB 3.2 Gen 2x1 (aka USB 3.1 Gen 2)

USB 3.2 Gen 2x2

USB 4

Thunderbolt 3 passive

Thunderbolt 3 active

Thunderbolt 4 passive

Thunderbolt 4 active

I had nearly forgotten about there being active vs. passive cables. Apparently with Thunderbolt 4 it's not as big of a deal any longer, and most of the time a passive Thunderbolt 4 cable will work, but there are still active Thunderbolt 4 cables as well. And I'm not sure if USB 4 has the same issue, but if it does, increase that number to eleven possible cables.

And given that we're up to at least ten now, that probably means I'm still missing some. Some of these cables are very expensive too, with Thunderbolt 4 cables costing at or around 60 USD per cable, I can't just go and replace every USB-C cable I own with a Thunderbolt 4 cable and call it a day.

USB-C is also a mess for charging, since voltages can be different. My ThinkPad uses USB-C to charge, and I thought that meant I could use a MacBook charger in a pinch, but no such luck.

@remmah that's strange. Over the last five years I've been charging two phones, one switch, two different MBPs, and one sweet of headphones with at least seven different power bricks and six different cables.

Never had an issue.

When I forgot the iPad charger on a holiday however...

@bri

Thank you for sharing. "But I can't easily tell if I'm getting the full bandwidth and charging capabilities of the device that I've connected using it! There's no easy way to find out, other than doing extensive and laborious testing" this sounds like it's a bit of a no issue compared to "this cable supply doesn't fit" which is what Apple are happily subjecting their customers to.

My point is that USBC with all its "only detectable by laborious testing" flaws, is superior to a bunch of proprietary and incompatible cables.

But at least now I've met somebody who has differed from the madness that USBC had unleashed on us

> it's a bit of a no issue compared to "this cable supply doesn't fit" which is what Apple are happily subjecting their customers to.

I'm not necessarily arguing against USB-C either. Having a plug that works universally is a great idea, and I've suffered plenty over the last two decades from Apple's various proprietary plugs.

It's just that we're still far away from that dream of universality, and right now we're in a situation where things are deceptive: the cable fits the plug, but oftentimes it just doesn't work. And it's because we rushed headlong into this "one connector to rule them all" idea without working out the details and issues. Hopefully in the not too distant future the situation will improve.

If only we had some sort of system for marking things with letters and numbers that can mean something at a glance but can be looked up to find the exact specification...

USB might have to go the route of electrical wire (like THHN, TWHN) where power/data/capacity has to be abbreviated and printed on the cable.

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