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USBefuddled: Untangling the Rat’s Nest of USB-C Standards and Cables

215 points by miles 5y ago

throwaway81523 5y ago
Useful article. I wish I could remember what the U in USB stood for. Maybe I don't want to know.
- you-liquidated 5y ago
  According to HN it stands for Unusable.
- charcircuit 5y ago
  USB stands for Universal Serial Bus. The U stands for Universal.
  - notreallyserio 5y ago
    As in there's a universe of standards for USB-C!
  - AnonHP 5y ago
    In case it wasn’t clear, the GP’s comment was sarcasm, considering the messy combinations that make it sound anything except universal.
  - Eelongate 5y ago
    I could have sworn they changed it to 'Uncertain Serial Bus'
tzs 5y ago
My understanding is that when you connect two devices together, they negotiate power (and data rate?), so the device supplying power won't supply a voltage that is too high for the consuming device and the consuming device won't try to draw too much current from the supplying device. Question: does the cable also tell the devices what it is capable of, so that if the devices are capable of 20 V and 5 A but the cable can only handle 5 V and 3 A that is all that the devices will actually do? Or will the devices happily go ahead and do 20 V and 5 A and set your cable on fire?
- AnotherGoodName 5y ago
  The big issue is thunderbolt. Sometimes you'll have to explain to people that the external display can only be connected by this USB port using this cable and not that USB port using that cable. "But they look exactly the same". Yes they do :(
  - api 5y ago
    Isn’t that the fault of thunderbolt for overloading the same connector for a different protocol?
    - kevin_thibedeau 5y ago
      USB3 does the same with alt mode supporting DisplayPort.
    - throw0101a 5y ago
      And yet USB does 'too little' overloading of the USB-C port: > Full-featured USB-C cables that implement USB 3.1 Gen 2 can handle up to 10 Gbit/s data rate at full duplex. They are marked with a SuperSpeed+ (SuperSpeed 10 Gbit/s) logo. There are also cables which can carry only USB 2.0 with up to 480 Mbit/s data rate. There are USB-IF certification programs available for USB-C products and end users are recommended to use USB-IF certified cables.[12] * https://en.wikipedia.org/wiki/USB-C#Cables https://en.wikipedia.org/wiki/USB-C#Cables Power delivery has a minimum of 60W (3A@20V) with support up to 100W (5A@20V), with a recent addition of 240W (5A@48V): * https://en.wikipedia.org/wiki/USB_hardware#USB_power_delivery https://en.wikipedia.org/wiki/USB_hardware#USB_power_deliver... And "USB-C" is not a monolithic entity, given there have been several revisions now (1.1, 1.2, 1.3, 1.4, 2.0, and 2.1 in May 2021).
- brundolf 5y ago
  There was a minor scandal a couple years ago where Nintendo's Switch console didn't implement the standard properly, and as a result some third-party docks were sending too much voltage and frying people's consoles
chx 5y ago
Some of this wrong, some of this is way too wordy. > USB-C cables that support Power Delivery 2.0 and 3.0 can carry a minimum of 7.5 watts (1.5 amps at 5 volts) or 15W (3A at 5V), depending on the device, cable, and purpose. Nope, all USB C cables are 60W minimum. The connector might support less, but the cables do support 60W minimum. > USB-C Charge Cable—designed in the early days of USB-C Nope, nothing wrong with a USB C cable which doesn't have the high speed lanes connected. That's a perfectly specification conformant cable. High speed lanes is the phrase I miss from this too long article. Here's a much shorter explanation of it all. A USB C cable always have separate wires for 1) power , either 60W or 100W capable. The latter needs an eMarker IC in the connector 2) a separate pair for 0.48Mbit/s speed USB data (aka USB 2.0) 3) it can have and most do have four high speed lanes (each lane is formed from two wires as differential pairs). These lanes can carry various data , by default it will use two lanes to carry USB data -- at at least 5gbps, if the cable is short enough then 10gbps. (While 20gbps mode over four lanes is defined so few hosts support this we don't need to care.) There are alternative modes besides USB, namely DisplayPort and Thunderbolt. In DisplayPort alternate mode it can use 2 or 4 lanes for DisplayPort. If two then the other two can be used for USB data as above. DisplayPort has its own versions: DisplayPort 1.2 can deliver 8.64 Gbit/s video data over two lanes, while 1.3/1.4 can carry 12.96 Gbit/s and for both double that over four lanes. (DisplayPort 1.4 introduces compression as well which needs to be supported by the monitor and it's very rare to do so.) This is aggregate video bandwidth for PCs: they can drive multiple monitors using a DisplayPort technology called MST. For Mac, you need Thunderbolt. Thunderbolt. Unlike the previous ones where the cable is functioning the same as a pre-USB C cable and a simple (basically, passive converter) can dole out USB and DisplayPort data this one is a complex bus and both ends needs to have a Thunderbolt controller. The Thunderbolt 3 bus can carry PCI Express and DisplayPort data (USB is provided by the controller presenting a hot plug root hub, due to hot plug nature there's a bevy of problems), the Thunderbolt 4 bus can carry PCI Express and DisplayPort and USB data. (Footnote: Thunderbolt 4 is the same as USB 4 with some optional features made mandatory. It is somewhat unlikely we will see non-TB4 USB 4 controllers so this is mostly just pedantry -- you can treat USB 4 and TB4 as being the same.) The bus bandwidth in one direction depending on cable length can be 20gbps or 40gbps. When allocating this bandwidth, DisplayPort has priority. How much DisplayPort is on the bus in total is a bit confusing due to some history: laptops with one Thunderbolt port most often will only put one DisplayPort 1.2 connection on the bus. Laptops with two ports always have full Thunderbolt and will put two DisplayPort connection on the bus (very rarely, single port laptops will do this too, mostly early workstations). This confusion goes away in Thunderbolt 4, that's always full. But the bus is never faster than 40gbps so even if it is fed by two DP 1.3/1.4 connections, it still can't deliver more than 40gbps data where two independent DisplayPort cables would be able to deliver slightly more than 50gpbs. Finally, power. If only 5V is required, resistors are used to signal how much power is requested. For 9/15/20V power is negotiated: the devices figure out which one is source and which one is sink, once that's done, the source will communicate how much power it is able to provide. At most 3A can be used normally, at 20V provided the right cable is present, 5A is also a possibility. There is a separate wire for this communication. Using the same communication process, the data roles are decided: one of them will be upstream (think host) one of them will be downstream (think peripheral). There's a sensible default where the upstream data role takes on the source power role but this can be changed using this negotiation. Footnote: these were fixed power. Today some devices support the PPS (Programmable Power Supplies) feature which allows the sink to rapidly change the wattage as needed. This also requires eMarker cables. And yes, cables are a mess. https://people.kernel.org/bleung/how-many-kinds-of-usb-c-to-usb-c-cables-are-there https://people.kernel.org/bleung/how-many-kinds-of-usb-c-to-...
xaduha 5y ago
In practice it has never been smoother for me. If I come across a crappy cable that isn't up to snuff I can easily get rid of it, I already have more than I need. It's not like previously when you had to keep some rare cables in case you needed them once in a blue moon.
- ewoodrich 5y ago
  Agreed. Being able to drive two 4K monitors, charge my laptop, and attach a USB hub via one USB-C connector is well worth the tradeoff of occasional incompatibility with cheap cables.
  - lambdaba 5y ago
    In an initial flurry of enthusiasm I bought a bunch of high-quality cables and I'm very glad I did. I can keep duplicate cables around in certain pockets etc. and I know I can always connect stuff. I had always used default supplier cables and these fancy ones feel much better in daily usage.
  - frosted-flakes 5y ago
    It's awesome being able to plop down on the couch and plug my laptop into a Nintendo Switch charger, that I also use to chargey phone. Charging a laptop before USB-C was an ordeal because I only had one specialised charger with a proprietary plug. Now I have half a dozen spread around the house and car.
    - deleted 5y ago
      [deleted]
    - simon1573 5y ago
      Between the proprietary plugs and USB-C, we had the dark ages of micro-USB which somehow always came loose after a few weeks of use
    - Yizahi 5y ago
      Funny that you mention Nintendo Switch, because Nintendo made a non-standard implementation of usb-c there and connecting console to the standard compliant cable and charger can brick or fry the console. Perfect example of USB-Confusion :)
SavantIdiot 5y ago
This is an incredibly thorough analysis of all the different kinds of things that can appear on the end of the USB-C. However, I think it puts blame on the hardware spec, when in reality the drivers are at fault. It is up to the driver to sort out the mess of options and provide feedback, however, engineers are not known for UX. All of the tools are there for querying caps, but this information simply doesn't propagate upstream to the GUI, so the user is left scratching their heads when they don't get bandwidth or connectivity. Recently I have started seeing devices alert me when they are plugged into a sub-optimal hub (e.g., Salae's USB-3 logic analyzer), but I think it will take some time for the driver/application space to catch up.
- thrashh 5y ago
  I blame the spec because if people commonly use what you designed the wrong way, you did not design it correctly.
  - SavantIdiot 5y ago
    That statement seems to lack consistency. You blame the spec, and then blame the designer. Which is it? EDIT: I worked t intel, the specification is written by the architects and the implementation is created by the designers. Two distinct groups of people.
    - eyelidlessness 5y ago
      I took it to mean the spec’s design.
    - james-skemp 5y ago
      By designers I believe they mean the authors of the spec. So unclear spec = implementations aren't as consistent as the authors of the spec were hoping for.
      - megous 5y ago
        What's unclear about what spec in particular? I've read PD, Type-C, BC1.2 specs and those are rather thorough and well cross-referenced.
spicybright 5y ago
TL;DR: Have manufacturers print the max data speed + wattage on cables.
- sokoloff 5y ago
  The following week: sellers on AliExpress are printing the max data speed + wattage on cables. (Not the max that this cable supports, necessarily, but the max they researched to exist.)
  - Shish2k 5y ago
    You’re very optimistic to think that they’d allow reality to limit them :) The first time I was buying 18650 batteries I naievely went for the largest advertised capacity, and got some whose claims broke the laws of physics… (And of course, in reality, the capacity didn’t even meet my minimum requirements)
spicybright 5y ago
I want a device where you plug both ends of a USB C cable in, and it reads out max data throughput + how much power it can push.
- kuon 5y ago
  Lab grade devices (like products from totalphase) that can do that properly are usually very expensive (like $20k). But there are some cheap boards around that might work (no guarantee): https://www.tindie.com/products/BitTradeOne/usb-cable-checker-2-assembled/ https://www.tindie.com/products/BitTradeOne/usb-cable-checke...
  - Hackbraten 5y ago
    Thanks for the link! I wish they shipped to Europe though.
Spunkie 5y ago
This seems like the place to ask, what is up with USBC displayport alt mode during boot/bios? Like I'm traveling with a usbc only monitor connected to a 6800xt and everything has been working fine with it until yesterday. I updated manjaro packages and the kernel to 5.15, and somehow that resulted in the monitor not working during boot anymore. Which I just don't understand the logistics of AT ALL. How does the host OS relate to video out during boot? The video out also didn't work once booted into linux but I was able to resolve this by replugging the monitor a couple of times after each restart. Ultimately reverting back to the 5.14 kernel fixed it in Linux but didn't fix it during boot. So now I just have to enter my LUKS pass blindly and hope for the best or that I never need to adjust my bios settings ever again. And on a slightly related side tangent how do people who switch to a bluetooth mouse/keyboard adjust their boot/bios? They just don't?
- robbedpeter 5y ago
  You have to rustle up a wired keyboard, at least. Fortunately, most hotels and motels will have them handy in their computer rooms, and almost any business will have a keyboard for you to try borrowing. I've been carrying my full sized wired keyboard along with my laptop since I had a laptop keyboard fail a few devices ago. I'd rather have a portable pc and monitor in a clunky case, the form factor of a laptop has always seemed the wrong solution for the problem being solved. Multiple pieces isn't a big deal.
- NavinF 5y ago
  > how do people who switch to a bluetooth mouse/keyboard adjust their boot/bios? Most wireless mouse/keyboard use the same USB HID drivers as the wired equivalents. So they work just fine in the BIOS/EFI. At least that’s been the case for every device I’ve used; I’m sure there are exceptions. That aside, fuck Bluetooth keyboards/mice. Even if you don’t play games, Bluetooth latency is very noticeable. I much prefer logitech lightspeed mice.
  - johnwalkr 5y ago
    Wireless keyboards that come with a USB adapter will work, but ones that connect to the computer’s Bluetooth usually do not.
AceJohnny2 5y ago
I wish there was a consumer-accessible tool that I could plug a USB-C cable in and it could tell me its capabilities. (I remember in the not-so-early days when Benson Leung, a Google Chromebook engineer, would on his own time buy and test cables on amazon and rate them. Some were actually dangerous and could fry your equipment!) Is it a "charge-only" cable that can only do USB2 speeds? How much power can it transport (if there's no id chip in the cable, perhaps this can be deduced by measuring the voltage droop when requesting various power modes over USB-PD)? Can it carry DisplayPort-over-Alternate Mode? -over-Thunderbolt? etc. Last I checked, 6 months ago, it seemed there was only lab-scale equipment that could do this.
- AceJohnny2 5y ago
  Tangentially, I've had great mileage out of the Satechi USB-C power-meter [1], which has demonstrated how cheap Amazon usb-c cables really don't carry as much power as Apple's expensive ones [1] Out of stock, but I'm sure there are others on the market: https://www.amazon.com/Satechi-USB-C-Power-Tester-Multimeter/dp/B01MT8MC3N https://www.amazon.com/Satechi-USB-C-Power-Tester-Multimeter...
  - johnwalkr 5y ago
    I was going to recommend this too! It feels high quality and has a nice, bright display as well.
  - ThatPlayer 5y ago
    Similarly I like my Witrn Qway U2 which does power meter but also gives you the ability to check which fast charge protocols are supported, and for USB-PD and QC3.0, the supported voltages and watts. You can even trigger them manually though I've broken some devices with this before.
- sephamorr 5y ago
  I dealt with USB-C hell when I was setting up my new office. BYO (choose your own) laptops meant that the USB-C ports on each employee's laptop had different capabilities (alt mode for DP 2-lanes? 4-lanes? HDMI? etc...) and the same for monitors and docks. I got about half way through designing this device (PCBs went out, firmware never written), intending it mostly for identifying sources and sinks before I had largely solved the office's problems and my needs faded. If there's collective interest, I could get back at it to finish the job.
nimish 5y ago
Fun fact: the USB4 20Gbps mode is not the same as the USB 3.2 Gen 2x2 20Gbps mode! That means there are 3 different 20Gbps cables if you include TB3.
- glennfle 5y ago
  I included only a partial list, as I feared if I listed all possible configurations, including wattage limits, it might be 60 items long!
watersb 5y ago
Just yesterday, I was telling myself I had been a fool to spend more money on yet more cable-ware, when I am surrounded by cables I don't need. But now I feel a lot better, thanks. Charging cables are set up in a couple of places in the house, aren't used for data. My dealer for charging cables is Rolling Square. They are nicely built and have complicated adapters on the ends that can handle all the USB-PD stuff, up to 100 Watts: https://rollingsquare.com https://rollingsquare.com Data-wise, they are just like Apple's charging cables: USB 2, 480 Mbit. For data, I go with OWC Thunderbolt 4 cables. My two-meter cable should arrive tomorrow. https://eshop.macsales.com/shop/owc-thunderbolt-4-cables https://eshop.macsales.com/shop/owc-thunderbolt-4-cables I feel like there should be a 12-Step program for this.
- kkjjkgjjgg 5y ago
  I guess the issue is that one type of cable is more expensive than the other? Otherwise I would prefer to have cables that can simply do everything.
  - watersb 5y ago
    Yes, the TB4 cables are more expensive than the ones intended for just charging. And the charging cables are designed to provide power to a range of USB devices, most of which were designed before USB-C Power Delivery was a thing. The charging cables have adapters on each end that can do USB-C Power Delivery, micro-USB with (I believe) "fast" charging per the Qualcomm or Samsung specs, or Apple Lightning. But yes, they don't have the re-timers necessary for 40 Gbit data. The Thunderbolt 4 cables cost about $50 right now (2 meters), about twice the price as the universal charging cables. All of these cables have E-Marker controllers at each end to negotiate all of these modes. I was able to find the data sheet for a common charger controller, made by Cirrus Semiconductor. It's a little ARM Cortex M0 computer. https://youtu.be/Sj62tJmONVA https://youtu.be/Sj62tJmONVA So a wired local area network of computers talk amongst themselves to figure out how to push energy and data around. Rolling Square was pricing their stuff at deep discount for Black Friday, a good value. Kickstarter products, they've been around for at least five years but might be clearing inventory before the new year. OWC, I think I was buying SCSI terminators from them back when the rubble of the Berlin Wall was still on the ground... One last thing FWIW -- For my travel bag, Rolling Square has a super short version that can fit in your pocket. One of those, a Thunderbolt cable, and a quality USB-PD charger can handle just about any situation. Crazy times.
parksy 5y ago
A small anecdote (side note- I seem to be turning into the old guy yells at cloud meme), though I'm a tech guy at heart it had been many years since I'd needed to know anything about USB's tech capabilities. Just over 15 years ago I was bit-banging over USB with an AVR device to retrofit some legacy DB-25 hardware / software into Windows / USB. So I figured I learned enough about USB to last a lifetime. Boy oh boy. Since then though I got lazy, fell behind in my knowledge, and was comfortable just being able to plug stuff in to charge / transfer data / whatever. It seemed like a solved problem so I went about my work without considering the ins and outs of a simple cable. I mean, it's just USB right? Different connectors, some carry more current, faster speeds over time etc, what more to know? Then mainly during early Covid when I was often switching between working from home vs in offices, I got sick of how many cables I needed to plug and unplug each morning and when I got home. I was inspired to solve this problem after one office I worked at had a USB-C dock that magically supported 2 displays, ethernet, etc. So I thought brilliant! I'd get one of those... Only they don't seem to exist / be in stock anywhere anymore, at least not without a long shipping delay from overseas. So after talking with a sales assistant at the local office supplies warehouse I grabbed something similar (and expensive for what essentially amounts to a fancy USB hub) off the shelf that had video support, and was saddened when it didn't work. That's when I read the instructions that were packaged with the device and apparently it only supported the USB-C with the little lightning bolt icon. Cue hours of reading and research to get up to speed on what all the different little icons I'd never noticed in the injection-moulded plastic meant. Okay my bad, I should have spent more time keeping up with technology and less time watching netflix. At least the dock worked for everything else, it wasn't ideal but I could deal with just 2 cables to swap out. But why then did the dock at the office work? I grabbed the model number and did some more research and lo and behold it has a built-in graphics adapter. So rather than outputting frames from my still quite capable GTX1070, some cruddy generic display chip was doing all the work through USB and some proprietary display drivers. I tried a couple of games as a benchmark and yep, FPS was woeful. That wouldn't do for my home office at all, so I nixed any hope of getting true video out via USB-C from this device. All told it was probably less than a day of actual time spent, and a hundred dollars so no big deal for me. But this experience led me to seriously consider that if someone like me with a strong interest and experience in tech gets sent for a spin by something that should be simple and "universal", I don't really understand how the average consumer is supposed to navigate it all. Sure, it's simple once you know, but it is niche knowledge, most people want to learn things about people, their jobs, stuff directly relevant to them and not memorize a grid of cable standards. So I'd wager most people don't read too deeply into it and either a cable/device "works" or is "broken / shit." Thinking of all the time wasted and frustration people must have swapping devices and cables, the sense that finding a magical combo that works creates a cargo-cult type mindset around brands and devices, as if it's all witchcraft voodoo. I wonder how many perfectly good cables and devices get returned or trashed each day because people think they're "broken." Anyway old guy has finished yelling at cloud for the day.
mattlondon 5y ago
The other annoying thing is that even if you get the right charger and right cables, you might only get power delivery for certain devices. E.g. a charger + cable combo that works fine with phones and Chromebooks, but plugin a Dell laptop and nothing happens. Same with older Mac chargers - they'd not do anything when I plug my phone in even if they charged laptops ok (or at least this was the case a few years back)
ashtonkem 5y ago
Maybe I’m lucky, but I have only ever had 1 problem with USB C, and it was a really minor case[0]. I just keep getting anker cables when I need them, and it always works. I keep reading about these spec issues, but I haven’t had any issues myself (aside from the one I listed). 0 - My double wide qi charger has a USB C socket, but came with a USB A brick and an A to C cable. That works fine, but when I plug it into my kitchen receptacle with built in USB C, it doesn’t work. I ended up moving that to another room for unrelated reasons, so not a big deal either way.
DeathArrow 5y ago
The article is excessively mentioning Apple. Apple is not the only computer maker, nor does it sell the most computers.
- kergonath 5y ago
  From TFA: > Thoughtful, detailed coverage of everything Apple for 31 years and the TidBITS Content Network for Apple professionals If you don’t want to read about Apple, you probably should find other websites.
DeathArrow 5y ago
Maybe USB-C cable and connectors could use two color codes. One for power delivery, one for data rate.
Causality1 5y ago
USB Type-C, almost universally called USB-C for short Where and by whom? In my experience it's always called "type c" for short, dropping the "USB" instead of the "type".
- smilespray 5y ago
  I've never heard it called "type c", only "usb c".
  - cesarb 5y ago
    I have; it's the name of the Linux subsystem for it (for instance /sys/class/typec has information on the device's USB-C ports).
- _ofdw 5y ago
  >Where and by whom? Well, literally every single person I've spoken to about it calls it either "thunderbolt" or "USB-C", or else they're boomers and call it "the round one". Not a single person I've encountered in real life calls it "type c".
deleted 5y ago
[deleted]
kuon 5y ago
I have a few devices that use type-A to type-A cables. Anybody has any idea why manufacturer does this? One example: http://www.magewell.com/products/usb-capture-hdmi-gen-2 http://www.magewell.com/products/usb-capture-hdmi-gen-2
- mkotowski 5y ago
  In my opinion it is probably something used as a cost-saving trick. Maybe some connectors/sockets/boards just happened to be cheaper that way at the moment. If the manufacturer do not care about being standard-compliant, you get something like that in the process. I mainly (only?) see such things in a more or less cheaply made “no-name” chinese-imported electronics.
  - kuon 5y ago
    Yeah, that is one explanation. But the magewell products are expensive and there have good linux support (only reason why I picked them), which is usually not found in cheap chinese products (even if I know magewell is chinese). I thought a bit more about it, and it seems they have have carefully selected an A type connector, in the documentation, they state we should not use an other cable. Maybe they have some electronic in their cable and used the A-A trick to prevent users from using another cable. I could take the cable to the electronic lab to have it tested, but sadly I don't have spare lying around and the devices are all in use.
- megous 5y ago
  Looking at the height of the chasis, fitting the B connector there might have been harder, and they likely didn't want to have a fixed cable.
thrower123 5y ago
I've still never owned a USB-C device. There is an enormous world of devices still shipping with micro-USB ports.
dig1 5y ago
I think USB-C solved some problems (no need to keep numerous different cables) but created another one - everything is now USB-C, and you can easily fry your things. My case: I lost the charger for T480 and purchased another one, not original from Lenovo, but something cheaper. I thought: the same specs, why should I pay 2-3x more. After two charges and a third attempted one, white smoke and smell of burned component. Motherboard replacement cost me almost 10x more of that original Lenovo charger. After this, I don't touch third-party USB-C cables unless they charge something I don't care about.
- vladvasiliu 5y ago
  But then again, you can now buy one (or more) "expensive" brand-name USB-C cables that will pretty much work with everything. The expensive Lenovo charger and cable will probably not fry the cheap junk you may have lying around. And it's still a win, you don't have to carry / find that one particular cable.
- tuatoru 5y ago
  This is a lovely illustration of the problems with USB-C. Anyone who thinks USB-C is better than the earlier variants has Stockholm Syndrome.
- NikolaNovak 5y ago
  Why is that a "usb c problem" as opposed to "cheap 3rd party charger problem"? I buy a lot of 3rd party chargers myself, but frying electronics with a bad cheap charger has existed long before usb c. (my personal life now with usb c is better... I buy a couple of quality chargers and cables and I'm good for everything. My Lenovo adapter can charge my phone in a pinch that's amazing! :)
  - exikyut 5y ago
    Because of the purported interoperability explicitly implied by the U in USB, and what people have come to expect that stands for, AND the fact that the specs spell out charging protocols, voltage restrictions/limiting, etc, backwards and upside down. It's a bit like a sort of "good" inverse of DRM: that specific charger's failure doesn't fall into a grey area, it squarely calls it out as bad, because "you get a certification" is gated on a manufacturer's word that they've implemented the spec, and correctly. (DRM, by comparison, implements a "thou shall not pass" that is sufficiently complex that passage incontrovertibly equates to breakage. Here, the "thou shall pass" is tied to some complexity that the manufacturer clearly promised they implemented, but didn't.) I expect the GP could reasonably report where they got the charger to the USB-IF, and theoretically cause the manufacturer in question to receive a bit of heat for what occurred. Practically speaking the state of things suggests that the USB-IF is probably dealing with enough of a firehose of such reports it probably takes sufficiently long for action to be taken that manufacturers practically get away with this sort of thing :'( Obviously if the charger was purchased from somewhere like Amazon it'd probably never get taken down without reasonable expense (purchasing additional units to prove danger) and media fanfare. Hahah.
hedora 5y ago
I wish we could just standardize on (say) 12 volts, with some barrel connector size that is currently unused. All cables that have the barrel must carry at least 250W. Current negotiation works like this: All power supplies must tolerate over current by optionally voltage drooping to 5V for 100ms, then (mandatory) tripping a breaker if overcurrent persists. Devices can binary search on the current draw, or not (so long as they actually trip the breaker and don’t just cycle on and off at 10hz). Plus on inside minus on outside for barrel connector. Done. Forever. The complete spec could fit on a page.
- detaro 5y ago
  so all cables and connectors rated for a bit over 20amps (i.e. more than your usual domestic socket, for reference what cable sizes that is), DC, with disconnection under load? That is highly impractical.
ksec 5y ago
>USB 4 basically implements Thunderbolt 3 inside the USB spec, making it a requirement for all USB 4 controllers That is not true. The support of Thunderbolt 3 is optional under USB4 spec. Along with a few other nitpick that is not entirely accurate. But it gets the point across And its time to tell the unpopular story again. ( Because USB-C Supporters hate it ) Trying to help a lawyer out and trying to explain why the $5.00 USB-C cable he'd bought from Amazon wasn't delivering 4K video to his expensive monitor AND powering his laptop too. Me: OK: so its a USB-C cable, but its not a high data rate USB-C cable. Him: But, its a USB-C Cable. Me: but, no, not all USB-C cables are high speed cables. And some of them can't do high speed and power delivery Him: but... its a USB-C cable: it plugs into the port. Me: Um... just because it plugs in, doesn't mean its going to work. You can have USB-C cables that are actually slower than the old USB ports. Him: but.... shouldn't it just work? And so on. For... 15? more minutes? maybe 30? I finally got him to buy a "proper" belkin USB-C cable . This basically sums up everything that is wrong with Tech thinking vs User Thinking.
- ziml77 5y ago
  I don't see that as a problem that can be solved. It's not like it's a new issue. The most direct equivalent is Ethernet cables. If you don't have the right category of cable for the speed and distance you're running, it's likely not going to work. Or it will work, but it will be slow due to packets constantly being retransmitted. Power cabling has a similar and more dangerous issue. Don't buy a cord with the correct wire gauge for your load and the length of the cord? That's a fire hazard.
- glennfle 5y ago
  Author of the article here—please do tell me more about the Thunderbolt 3 and USB 4 relationship. I used “basically” to hand wave over some of the detail, but would love to know how to dig down on this further. (And I welcome nit picks. Seriously! We just did a couple tweaks. Some folks who buy HDDs said they see 3.0 Micro-B all the time, and that is absolutely true, so we modified a sentence about that.) I'm leaning a bit on three things: • The USB-IF says that USB 4 is based on Thunderbolt 3 and incorporates Thunderbolt 3. If it's optional, they buried it in the spec? Would love to know where if you do so I can make that clearer. (See https://www.usb.org/usb4 https://www.usb.org/usb4 for instance.) • Apple’s USB 4/Thunderbolt 4 controller ostensibly incorporates all previous standards with backwards compatibility, so the question will likely arise in a specific case: a Thunderbolt 3 device with a Thunderbolt 3 controller attached to a USB 4 controller that isn’t a Thunderbolt 4 controller. In that case, the host computer’s USB 4 controller would have to negotiate down to 10 Gbps and USB 3.1 Gen 2? (???) • In practice, I wonder which controller modules major brands besides Apple will adopt: it seems most likely they would want USB4/TB4 not USB 4-only? Per the above about the lawyer, too, the USB-C Charging Cable Apple offers (no video, 480 Mbps USB 2.0 data, and up to 100W power) is absolutely the most maddening cable on the market.

215 points by miles 5y ago

throwaway81523 5y ago

Useful article. I wish I could remember what the U in USB stood for. Maybe I don't want to know.

you-liquidated 5y ago
According to HN it stands for Unusable.
charcircuit 5y ago
USB stands for Universal Serial Bus. The U stands for Universal.
- notreallyserio 5y ago
  As in there's a universe of standards for USB-C!
- AnonHP 5y ago
  In case it wasn’t clear, the GP’s comment was sarcasm, considering the messy combinations that make it sound anything except universal.
- Eelongate 5y ago
  I could have sworn they changed it to 'Uncertain Serial Bus'

tzs 5y ago

My understanding is that when you connect two devices together, they negotiate power (and data rate?), so the device supplying power won't supply a voltage that is too high for the consuming device and the consuming device won't try to draw too much current from the supplying device. Question: does the cable also tell the devices what it is capable of, so that if the devices are capable of 20 V and 5 A but the cable can only handle 5 V and 3 A that is all that the devices will actually do? Or will the devices happily go ahead and do 20 V and 5 A and set your cable on fire?

AnotherGoodName 5y ago
The big issue is thunderbolt. Sometimes you'll have to explain to people that the external display can only be connected by this USB port using this cable and not that USB port using that cable. "But they look exactly the same". Yes they do :(
- api 5y ago
  Isn’t that the fault of thunderbolt for overloading the same connector for a different protocol?
  - kevin_thibedeau 5y ago
    USB3 does the same with alt mode supporting DisplayPort.
  - throw0101a 5y ago
    And yet USB does 'too little' overloading of the USB-C port: > Full-featured USB-C cables that implement USB 3.1 Gen 2 can handle up to 10 Gbit/s data rate at full duplex. They are marked with a SuperSpeed+ (SuperSpeed 10 Gbit/s) logo. There are also cables which can carry only USB 2.0 with up to 480 Mbit/s data rate. There are USB-IF certification programs available for USB-C products and end users are recommended to use USB-IF certified cables.[12] * https://en.wikipedia.org/wiki/USB-C#Cables https://en.wikipedia.org/wiki/USB-C#Cables Power delivery has a minimum of 60W (3A@20V) with support up to 100W (5A@20V), with a recent addition of 240W (5A@48V): * https://en.wikipedia.org/wiki/USB_hardware#USB_power_delivery https://en.wikipedia.org/wiki/USB_hardware#USB_power_deliver... And "USB-C" is not a monolithic entity, given there have been several revisions now (1.1, 1.2, 1.3, 1.4, 2.0, and 2.1 in May 2021).
brundolf 5y ago
There was a minor scandal a couple years ago where Nintendo's Switch console didn't implement the standard properly, and as a result some third-party docks were sending too much voltage and frying people's consoles

chx 5y ago

Some of this wrong, some of this is way too wordy. > USB-C cables that support Power Delivery 2.0 and 3.0 can carry a minimum of 7.5 watts (1.5 amps at 5 volts) or 15W (3A at 5V), depending on the device, cable, and purpose. Nope, all USB C cables are 60W minimum. The connector might support less, but the cables do support 60W minimum. > USB-C Charge Cable—designed in the early days of USB-C Nope, nothing wrong with a USB C cable which doesn't have the high speed lanes connected. That's a perfectly specification conformant cable. High speed lanes is the phrase I miss from this too long article. Here's a much shorter explanation of it all. A USB C cable always have separate wires for 1) power , either 60W or 100W capable. The latter needs an eMarker IC in the connector 2) a separate pair for 0.48Mbit/s speed USB data (aka USB 2.0) 3) it can have and most do have four high speed lanes (each lane is formed from two wires as differential pairs). These lanes can carry various data , by default it will use two lanes to carry USB data -- at at least 5gbps, if the cable is short enough then 10gbps. (While 20gbps mode over four lanes is defined so few hosts support this we don't need to care.) There are alternative modes besides USB, namely DisplayPort and Thunderbolt. In DisplayPort alternate mode it can use 2 or 4 lanes for DisplayPort. If two then the other two can be used for USB data as above. DisplayPort has its own versions: DisplayPort 1.2 can deliver 8.64 Gbit/s video data over two lanes, while 1.3/1.4 can carry 12.96 Gbit/s and for both double that over four lanes. (DisplayPort 1.4 introduces compression as well which needs to be supported by the monitor and it's very rare to do so.) This is aggregate video bandwidth for PCs: they can drive multiple monitors using a DisplayPort technology called MST. For Mac, you need Thunderbolt. Thunderbolt. Unlike the previous ones where the cable is functioning the same as a pre-USB C cable and a simple (basically, passive converter) can dole out USB and DisplayPort data this one is a complex bus and both ends needs to have a Thunderbolt controller. The Thunderbolt 3 bus can carry PCI Express and DisplayPort data (USB is provided by the controller presenting a hot plug root hub, due to hot plug nature there's a bevy of problems), the Thunderbolt 4 bus can carry PCI Express and DisplayPort and USB data. (Footnote: Thunderbolt 4 is the same as USB 4 with some optional features made mandatory. It is somewhat unlikely we will see non-TB4 USB 4 controllers so this is mostly just pedantry -- you can treat USB 4 and TB4 as being the same.) The bus bandwidth in one direction depending on cable length can be 20gbps or 40gbps. When allocating this bandwidth, DisplayPort has priority. How much DisplayPort is on the bus in total is a bit confusing due to some history: laptops with one Thunderbolt port most often will only put one DisplayPort 1.2 connection on the bus. Laptops with two ports always have full Thunderbolt and will put two DisplayPort connection on the bus (very rarely, single port laptops will do this too, mostly early workstations). This confusion goes away in Thunderbolt 4, that's always full. But the bus is never faster than 40gbps so even if it is fed by two DP 1.3/1.4 connections, it still can't deliver more than 40gbps data where two independent DisplayPort cables would be able to deliver slightly more than 50gpbs. Finally, power. If only 5V is required, resistors are used to signal how much power is requested. For 9/15/20V power is negotiated: the devices figure out which one is source and which one is sink, once that's done, the source will communicate how much power it is able to provide. At most 3A can be used normally, at 20V provided the right cable is present, 5A is also a possibility. There is a separate wire for this communication. Using the same communication process, the data roles are decided: one of them will be upstream (think host) one of them will be downstream (think peripheral). There's a sensible default where the upstream data role takes on the source power role but this can be changed using this negotiation. Footnote: these were fixed power. Today some devices support the PPS (Programmable Power Supplies) feature which allows the sink to rapidly change the wattage as needed. This also requires eMarker cables. And yes, cables are a mess. https://people.kernel.org/bleung/how-many-kinds-of-usb-c-to-usb-c-cables-are-there https://people.kernel.org/bleung/how-many-kinds-of-usb-c-to-...

xaduha 5y ago

In practice it has never been smoother for me. If I come across a crappy cable that isn't up to snuff I can easily get rid of it, I already have more than I need. It's not like previously when you had to keep some rare cables in case you needed them once in a blue moon.

ewoodrich 5y ago
Agreed. Being able to drive two 4K monitors, charge my laptop, and attach a USB hub via one USB-C connector is well worth the tradeoff of occasional incompatibility with cheap cables.
- lambdaba 5y ago
  In an initial flurry of enthusiasm I bought a bunch of high-quality cables and I'm very glad I did. I can keep duplicate cables around in certain pockets etc. and I know I can always connect stuff. I had always used default supplier cables and these fancy ones feel much better in daily usage.
- frosted-flakes 5y ago
  It's awesome being able to plop down on the couch and plug my laptop into a Nintendo Switch charger, that I also use to chargey phone. Charging a laptop before USB-C was an ordeal because I only had one specialised charger with a proprietary plug. Now I have half a dozen spread around the house and car.
  - deleted 5y ago
    [deleted]
  - simon1573 5y ago
    Between the proprietary plugs and USB-C, we had the dark ages of micro-USB which somehow always came loose after a few weeks of use
  - Yizahi 5y ago
    Funny that you mention Nintendo Switch, because Nintendo made a non-standard implementation of usb-c there and connecting console to the standard compliant cable and charger can brick or fry the console. Perfect example of USB-Confusion :)

SavantIdiot 5y ago

This is an incredibly thorough analysis of all the different kinds of things that can appear on the end of the USB-C. However, I think it puts blame on the hardware spec, when in reality the drivers are at fault. It is up to the driver to sort out the mess of options and provide feedback, however, engineers are not known for UX. All of the tools are there for querying caps, but this information simply doesn't propagate upstream to the GUI, so the user is left scratching their heads when they don't get bandwidth or connectivity. Recently I have started seeing devices alert me when they are plugged into a sub-optimal hub (e.g., Salae's USB-3 logic analyzer), but I think it will take some time for the driver/application space to catch up.

thrashh 5y ago
I blame the spec because if people commonly use what you designed the wrong way, you did not design it correctly.
- SavantIdiot 5y ago
  That statement seems to lack consistency. You blame the spec, and then blame the designer. Which is it? EDIT: I worked t intel, the specification is written by the architects and the implementation is created by the designers. Two distinct groups of people.
  - eyelidlessness 5y ago
    I took it to mean the spec’s design.
  - james-skemp 5y ago
    By designers I believe they mean the authors of the spec. So unclear spec = implementations aren't as consistent as the authors of the spec were hoping for.
    - megous 5y ago
      What's unclear about what spec in particular? I've read PD, Type-C, BC1.2 specs and those are rather thorough and well cross-referenced.

spicybright 5y ago

TL;DR: Have manufacturers print the max data speed + wattage on cables.

sokoloff 5y ago
The following week: sellers on AliExpress are printing the max data speed + wattage on cables. (Not the max that this cable supports, necessarily, but the max they researched to exist.)
- Shish2k 5y ago
  You’re very optimistic to think that they’d allow reality to limit them :) The first time I was buying 18650 batteries I naievely went for the largest advertised capacity, and got some whose claims broke the laws of physics… (And of course, in reality, the capacity didn’t even meet my minimum requirements)

spicybright 5y ago

I want a device where you plug both ends of a USB C cable in, and it reads out max data throughput + how much power it can push.

kuon 5y ago
Lab grade devices (like products from totalphase) that can do that properly are usually very expensive (like $20k). But there are some cheap boards around that might work (no guarantee): https://www.tindie.com/products/BitTradeOne/usb-cable-checker-2-assembled/ https://www.tindie.com/products/BitTradeOne/usb-cable-checke...
- Hackbraten 5y ago
  Thanks for the link! I wish they shipped to Europe though.

Spunkie 5y ago

This seems like the place to ask, what is up with USBC displayport alt mode during boot/bios? Like I'm traveling with a usbc only monitor connected to a 6800xt and everything has been working fine with it until yesterday. I updated manjaro packages and the kernel to 5.15, and somehow that resulted in the monitor not working during boot anymore. Which I just don't understand the logistics of AT ALL. How does the host OS relate to video out during boot? The video out also didn't work once booted into linux but I was able to resolve this by replugging the monitor a couple of times after each restart. Ultimately reverting back to the 5.14 kernel fixed it in Linux but didn't fix it during boot. So now I just have to enter my LUKS pass blindly and hope for the best or that I never need to adjust my bios settings ever again. And on a slightly related side tangent how do people who switch to a bluetooth mouse/keyboard adjust their boot/bios? They just don't?

robbedpeter 5y ago
You have to rustle up a wired keyboard, at least. Fortunately, most hotels and motels will have them handy in their computer rooms, and almost any business will have a keyboard for you to try borrowing. I've been carrying my full sized wired keyboard along with my laptop since I had a laptop keyboard fail a few devices ago. I'd rather have a portable pc and monitor in a clunky case, the form factor of a laptop has always seemed the wrong solution for the problem being solved. Multiple pieces isn't a big deal.
NavinF 5y ago
> how do people who switch to a bluetooth mouse/keyboard adjust their boot/bios? Most wireless mouse/keyboard use the same USB HID drivers as the wired equivalents. So they work just fine in the BIOS/EFI. At least that’s been the case for every device I’ve used; I’m sure there are exceptions. That aside, fuck Bluetooth keyboards/mice. Even if you don’t play games, Bluetooth latency is very noticeable. I much prefer logitech lightspeed mice.
- johnwalkr 5y ago
  Wireless keyboards that come with a USB adapter will work, but ones that connect to the computer’s Bluetooth usually do not.

AceJohnny2 5y ago

I wish there was a consumer-accessible tool that I could plug a USB-C cable in and it could tell me its capabilities. (I remember in the not-so-early days when Benson Leung, a Google Chromebook engineer, would on his own time buy and test cables on amazon and rate them. Some were actually dangerous and could fry your equipment!) Is it a "charge-only" cable that can only do USB2 speeds? How much power can it transport (if there's no id chip in the cable, perhaps this can be deduced by measuring the voltage droop when requesting various power modes over USB-PD)? Can it carry DisplayPort-over-Alternate Mode? -over-Thunderbolt? etc. Last I checked, 6 months ago, it seemed there was only lab-scale equipment that could do this.

AceJohnny2 5y ago
Tangentially, I've had great mileage out of the Satechi USB-C power-meter [1], which has demonstrated how cheap Amazon usb-c cables really don't carry as much power as Apple's expensive ones [1] Out of stock, but I'm sure there are others on the market: https://www.amazon.com/Satechi-USB-C-Power-Tester-Multimeter/dp/B01MT8MC3N https://www.amazon.com/Satechi-USB-C-Power-Tester-Multimeter...
- johnwalkr 5y ago
  I was going to recommend this too! It feels high quality and has a nice, bright display as well.
- ThatPlayer 5y ago
  Similarly I like my Witrn Qway U2 which does power meter but also gives you the ability to check which fast charge protocols are supported, and for USB-PD and QC3.0, the supported voltages and watts. You can even trigger them manually though I've broken some devices with this before.
sephamorr 5y ago
I dealt with USB-C hell when I was setting up my new office. BYO (choose your own) laptops meant that the USB-C ports on each employee's laptop had different capabilities (alt mode for DP 2-lanes? 4-lanes? HDMI? etc...) and the same for monitors and docks. I got about half way through designing this device (PCBs went out, firmware never written), intending it mostly for identifying sources and sinks before I had largely solved the office's problems and my needs faded. If there's collective interest, I could get back at it to finish the job.

nimish 5y ago

Fun fact: the USB4 20Gbps mode is not the same as the USB 3.2 Gen 2x2 20Gbps mode! That means there are 3 different 20Gbps cables if you include TB3.

glennfle 5y ago
I included only a partial list, as I feared if I listed all possible configurations, including wattage limits, it might be 60 items long!

watersb 5y ago

Just yesterday, I was telling myself I had been a fool to spend more money on yet more cable-ware, when I am surrounded by cables I don't need. But now I feel a lot better, thanks. Charging cables are set up in a couple of places in the house, aren't used for data. My dealer for charging cables is Rolling Square. They are nicely built and have complicated adapters on the ends that can handle all the USB-PD stuff, up to 100 Watts: https://rollingsquare.com https://rollingsquare.com Data-wise, they are just like Apple's charging cables: USB 2, 480 Mbit. For data, I go with OWC Thunderbolt 4 cables. My two-meter cable should arrive tomorrow. https://eshop.macsales.com/shop/owc-thunderbolt-4-cables https://eshop.macsales.com/shop/owc-thunderbolt-4-cables I feel like there should be a 12-Step program for this.

kkjjkgjjgg 5y ago
I guess the issue is that one type of cable is more expensive than the other? Otherwise I would prefer to have cables that can simply do everything.
- watersb 5y ago
  Yes, the TB4 cables are more expensive than the ones intended for just charging. And the charging cables are designed to provide power to a range of USB devices, most of which were designed before USB-C Power Delivery was a thing. The charging cables have adapters on each end that can do USB-C Power Delivery, micro-USB with (I believe) "fast" charging per the Qualcomm or Samsung specs, or Apple Lightning. But yes, they don't have the re-timers necessary for 40 Gbit data. The Thunderbolt 4 cables cost about $50 right now (2 meters), about twice the price as the universal charging cables. All of these cables have E-Marker controllers at each end to negotiate all of these modes. I was able to find the data sheet for a common charger controller, made by Cirrus Semiconductor. It's a little ARM Cortex M0 computer. https://youtu.be/Sj62tJmONVA https://youtu.be/Sj62tJmONVA So a wired local area network of computers talk amongst themselves to figure out how to push energy and data around. Rolling Square was pricing their stuff at deep discount for Black Friday, a good value. Kickstarter products, they've been around for at least five years but might be clearing inventory before the new year. OWC, I think I was buying SCSI terminators from them back when the rubble of the Berlin Wall was still on the ground... One last thing FWIW -- For my travel bag, Rolling Square has a super short version that can fit in your pocket. One of those, a Thunderbolt cable, and a quality USB-PD charger can handle just about any situation. Crazy times.

parksy 5y ago

A small anecdote (side note- I seem to be turning into the old guy yells at cloud meme), though I'm a tech guy at heart it had been many years since I'd needed to know anything about USB's tech capabilities. Just over 15 years ago I was bit-banging over USB with an AVR device to retrofit some legacy DB-25 hardware / software into Windows / USB. So I figured I learned enough about USB to last a lifetime. Boy oh boy. Since then though I got lazy, fell behind in my knowledge, and was comfortable just being able to plug stuff in to charge / transfer data / whatever. It seemed like a solved problem so I went about my work without considering the ins and outs of a simple cable. I mean, it's just USB right? Different connectors, some carry more current, faster speeds over time etc, what more to know? Then mainly during early Covid when I was often switching between working from home vs in offices, I got sick of how many cables I needed to plug and unplug each morning and when I got home. I was inspired to solve this problem after one office I worked at had a USB-C dock that magically supported 2 displays, ethernet, etc. So I thought brilliant! I'd get one of those... Only they don't seem to exist / be in stock anywhere anymore, at least not without a long shipping delay from overseas. So after talking with a sales assistant at the local office supplies warehouse I grabbed something similar (and expensive for what essentially amounts to a fancy USB hub) off the shelf that had video support, and was saddened when it didn't work. That's when I read the instructions that were packaged with the device and apparently it only supported the USB-C with the little lightning bolt icon. Cue hours of reading and research to get up to speed on what all the different little icons I'd never noticed in the injection-moulded plastic meant. Okay my bad, I should have spent more time keeping up with technology and less time watching netflix. At least the dock worked for everything else, it wasn't ideal but I could deal with just 2 cables to swap out. But why then did the dock at the office work? I grabbed the model number and did some more research and lo and behold it has a built-in graphics adapter. So rather than outputting frames from my still quite capable GTX1070, some cruddy generic display chip was doing all the work through USB and some proprietary display drivers. I tried a couple of games as a benchmark and yep, FPS was woeful. That wouldn't do for my home office at all, so I nixed any hope of getting true video out via USB-C from this device. All told it was probably less than a day of actual time spent, and a hundred dollars so no big deal for me. But this experience led me to seriously consider that if someone like me with a strong interest and experience in tech gets sent for a spin by something that should be simple and "universal", I don't really understand how the average consumer is supposed to navigate it all. Sure, it's simple once you know, but it is niche knowledge, most people want to learn things about people, their jobs, stuff directly relevant to them and not memorize a grid of cable standards. So I'd wager most people don't read too deeply into it and either a cable/device "works" or is "broken / shit." Thinking of all the time wasted and frustration people must have swapping devices and cables, the sense that finding a magical combo that works creates a cargo-cult type mindset around brands and devices, as if it's all witchcraft voodoo. I wonder how many perfectly good cables and devices get returned or trashed each day because people think they're "broken." Anyway old guy has finished yelling at cloud for the day.

mattlondon 5y ago

The other annoying thing is that even if you get the right charger and right cables, you might only get power delivery for certain devices. E.g. a charger + cable combo that works fine with phones and Chromebooks, but plugin a Dell laptop and nothing happens. Same with older Mac chargers - they'd not do anything when I plug my phone in even if they charged laptops ok (or at least this was the case a few years back)

ashtonkem 5y ago

Maybe I’m lucky, but I have only ever had 1 problem with USB C, and it was a really minor case[0]. I just keep getting anker cables when I need them, and it always works. I keep reading about these spec issues, but I haven’t had any issues myself (aside from the one I listed). 0 - My double wide qi charger has a USB C socket, but came with a USB A brick and an A to C cable. That works fine, but when I plug it into my kitchen receptacle with built in USB C, it doesn’t work. I ended up moving that to another room for unrelated reasons, so not a big deal either way.

DeathArrow 5y ago

The article is excessively mentioning Apple. Apple is not the only computer maker, nor does it sell the most computers.

kergonath 5y ago
From TFA: > Thoughtful, detailed coverage of everything Apple for 31 years and the TidBITS Content Network for Apple professionals If you don’t want to read about Apple, you probably should find other websites.

DeathArrow 5y ago

Maybe USB-C cable and connectors could use two color codes. One for power delivery, one for data rate.

Causality1 5y ago

USB Type-C, almost universally called USB-C for short Where and by whom? In my experience it's always called "type c" for short, dropping the "USB" instead of the "type".

smilespray 5y ago
I've never heard it called "type c", only "usb c".
- cesarb 5y ago
  I have; it's the name of the Linux subsystem for it (for instance /sys/class/typec has information on the device's USB-C ports).
_ofdw 5y ago
>Where and by whom? Well, literally every single person I've spoken to about it calls it either "thunderbolt" or "USB-C", or else they're boomers and call it "the round one". Not a single person I've encountered in real life calls it "type c".

deleted 5y ago

[deleted]

kuon 5y ago

I have a few devices that use type-A to type-A cables. Anybody has any idea why manufacturer does this? One example: http://www.magewell.com/products/usb-capture-hdmi-gen-2 http://www.magewell.com/products/usb-capture-hdmi-gen-2

mkotowski 5y ago
In my opinion it is probably something used as a cost-saving trick. Maybe some connectors/sockets/boards just happened to be cheaper that way at the moment. If the manufacturer do not care about being standard-compliant, you get something like that in the process. I mainly (only?) see such things in a more or less cheaply made “no-name” chinese-imported electronics.
- kuon 5y ago
  Yeah, that is one explanation. But the magewell products are expensive and there have good linux support (only reason why I picked them), which is usually not found in cheap chinese products (even if I know magewell is chinese). I thought a bit more about it, and it seems they have have carefully selected an A type connector, in the documentation, they state we should not use an other cable. Maybe they have some electronic in their cable and used the A-A trick to prevent users from using another cable. I could take the cable to the electronic lab to have it tested, but sadly I don't have spare lying around and the devices are all in use.
megous 5y ago
Looking at the height of the chasis, fitting the B connector there might have been harder, and they likely didn't want to have a fixed cable.

thrower123 5y ago

I've still never owned a USB-C device. There is an enormous world of devices still shipping with micro-USB ports.

dig1 5y ago

I think USB-C solved some problems (no need to keep numerous different cables) but created another one - everything is now USB-C, and you can easily fry your things. My case: I lost the charger for T480 and purchased another one, not original from Lenovo, but something cheaper. I thought: the same specs, why should I pay 2-3x more. After two charges and a third attempted one, white smoke and smell of burned component. Motherboard replacement cost me almost 10x more of that original Lenovo charger. After this, I don't touch third-party USB-C cables unless they charge something I don't care about.

vladvasiliu 5y ago
But then again, you can now buy one (or more) "expensive" brand-name USB-C cables that will pretty much work with everything. The expensive Lenovo charger and cable will probably not fry the cheap junk you may have lying around. And it's still a win, you don't have to carry / find that one particular cable.
tuatoru 5y ago
This is a lovely illustration of the problems with USB-C. Anyone who thinks USB-C is better than the earlier variants has Stockholm Syndrome.
NikolaNovak 5y ago
Why is that a "usb c problem" as opposed to "cheap 3rd party charger problem"? I buy a lot of 3rd party chargers myself, but frying electronics with a bad cheap charger has existed long before usb c. (my personal life now with usb c is better... I buy a couple of quality chargers and cables and I'm good for everything. My Lenovo adapter can charge my phone in a pinch that's amazing! :)
- exikyut 5y ago
  Because of the purported interoperability explicitly implied by the U in USB, and what people have come to expect that stands for, AND the fact that the specs spell out charging protocols, voltage restrictions/limiting, etc, backwards and upside down. It's a bit like a sort of "good" inverse of DRM: that specific charger's failure doesn't fall into a grey area, it squarely calls it out as bad, because "you get a certification" is gated on a manufacturer's word that they've implemented the spec, and correctly. (DRM, by comparison, implements a "thou shall not pass" that is sufficiently complex that passage incontrovertibly equates to breakage. Here, the "thou shall pass" is tied to some complexity that the manufacturer clearly promised they implemented, but didn't.) I expect the GP could reasonably report where they got the charger to the USB-IF, and theoretically cause the manufacturer in question to receive a bit of heat for what occurred. Practically speaking the state of things suggests that the USB-IF is probably dealing with enough of a firehose of such reports it probably takes sufficiently long for action to be taken that manufacturers practically get away with this sort of thing :'( Obviously if the charger was purchased from somewhere like Amazon it'd probably never get taken down without reasonable expense (purchasing additional units to prove danger) and media fanfare. Hahah.

hedora 5y ago

I wish we could just standardize on (say) 12 volts, with some barrel connector size that is currently unused. All cables that have the barrel must carry at least 250W. Current negotiation works like this: All power supplies must tolerate over current by optionally voltage drooping to 5V for 100ms, then (mandatory) tripping a breaker if overcurrent persists. Devices can binary search on the current draw, or not (so long as they actually trip the breaker and don’t just cycle on and off at 10hz). Plus on inside minus on outside for barrel connector. Done. Forever. The complete spec could fit on a page.

detaro 5y ago
so all cables and connectors rated for a bit over 20amps (i.e. more than your usual domestic socket, for reference what cable sizes that is), DC, with disconnection under load? That is highly impractical.

ksec 5y ago

>USB 4 basically implements Thunderbolt 3 inside the USB spec, making it a requirement for all USB 4 controllers That is not true. The support of Thunderbolt 3 is optional under USB4 spec. Along with a few other nitpick that is not entirely accurate. But it gets the point across And its time to tell the unpopular story again. ( Because USB-C Supporters hate it ) Trying to help a lawyer out and trying to explain why the $5.00 USB-C cable he'd bought from Amazon wasn't delivering 4K video to his expensive monitor AND powering his laptop too. Me: OK: so its a USB-C cable, but its not a high data rate USB-C cable. Him: But, its a USB-C Cable. Me: but, no, not all USB-C cables are high speed cables. And some of them can't do high speed and power delivery Him: but... its a USB-C cable: it plugs into the port. Me: Um... just because it plugs in, doesn't mean its going to work. You can have USB-C cables that are actually slower than the old USB ports. Him: but.... shouldn't it just work? And so on. For... 15? more minutes? maybe 30? I finally got him to buy a "proper" belkin USB-C cable . This basically sums up everything that is wrong with Tech thinking vs User Thinking.

ziml77 5y ago
I don't see that as a problem that can be solved. It's not like it's a new issue. The most direct equivalent is Ethernet cables. If you don't have the right category of cable for the speed and distance you're running, it's likely not going to work. Or it will work, but it will be slow due to packets constantly being retransmitted. Power cabling has a similar and more dangerous issue. Don't buy a cord with the correct wire gauge for your load and the length of the cord? That's a fire hazard.
glennfle 5y ago
Author of the article here—please do tell me more about the Thunderbolt 3 and USB 4 relationship. I used “basically” to hand wave over some of the detail, but would love to know how to dig down on this further. (And I welcome nit picks. Seriously! We just did a couple tweaks. Some folks who buy HDDs said they see 3.0 Micro-B all the time, and that is absolutely true, so we modified a sentence about that.) I'm leaning a bit on three things: • The USB-IF says that USB 4 is based on Thunderbolt 3 and incorporates Thunderbolt 3. If it's optional, they buried it in the spec? Would love to know where if you do so I can make that clearer. (See https://www.usb.org/usb4 https://www.usb.org/usb4 for instance.) • Apple’s USB 4/Thunderbolt 4 controller ostensibly incorporates all previous standards with backwards compatibility, so the question will likely arise in a specific case: a Thunderbolt 3 device with a Thunderbolt 3 controller attached to a USB 4 controller that isn’t a Thunderbolt 4 controller. In that case, the host computer’s USB 4 controller would have to negotiate down to 10 Gbps and USB 3.1 Gen 2? (???) • In practice, I wonder which controller modules major brands besides Apple will adopt: it seems most likely they would want USB4/TB4 not USB 4-only? Per the above about the lawyer, too, the USB-C Charging Cable Apple offers (no video, 480 Mbps USB 2.0 data, and up to 100W power) is absolutely the most maddening cable on the market.