4 ms·
USB Cheat Sheet (2022)
- brcmthrowaway 5mo agoWhere does TB5 come into all of this?
- Neywiny 5mo agoI don't see why it would. Thunderbolt is not a USB standard
- Kirby64 5mo agoThunderbolt 5 and USB4v2 are the same thing now. They both support 80gbps and pcie pass through.
- aleph_minus_one 5mo ago> Thunderbolt 5 and USB4v2 are the same thing now. They both support 80gbps and pcie pass through. Not completely true: Thunderbolt 5 demands some capabilities that are optional for USB4v2.
- Kirby64 5mo agoFrom a protocol/bandwidth level, it’s essentially the same though. Thunderbolt 5 has some more guarantees for power and display, but the data rate of the two is the same.
- stevex 5mo agoDoesn't it run over a USB-C shaped wire? If you're trying to understand things that plug into USB-shaped ports it seems at least worth mentioning.
- DiabloD3 5mo agoTo be fair: You should refer to these as Type-C cables, as they carry things that are not USB protocol. The sole exception should be made for "charge only" cables, which can, and should, be referred to as "wired for USB 2.0". These cables "shouldn't" exist, but I also don't want to buy a $30 cable just to charge my phone.
- aleph_minus_one 5mo ago> Thunderbolt is not a USB standard Concerning Thunderbolt 3: USB4 is based on the Thunderbolt 3 protocol [1]. Concerning Thunderbolt 4: "In July 2020 Intel announced Thunderbolt 4 as an implementation of USB4 40 Gbit/s with additional requirements, such as mandatory backward compatibility to Thunderbolt 3 and requirement for smaller notebooks to support being charged over Thunderbolt 4 ports.[14] Publications such as AnandTech described Thunderbolt 4 as "superset of TB3 and USB4" and "able to accept TB4, TB3, USB4, and USB 3/2/1 connections"." [2] Concerning Thunderbolt 5: Intel considers Thunderbolt 5 as an implementation of USB4 Version 2.0. [3] [1] https://en.wikipedia.org/w/index.php?title=USB4&oldid=1347428772 https://en.wikipedia.org/w/index.php?title=USB4&oldid=134742... [2] https://en.wikipedia.org/w/index.php?title=USB4&oldid=1347428772#USB4_Version_1.0 https://en.wikipedia.org/w/index.php?title=USB4&oldid=134742... [3] https://en.wikipedia.org/w/index.php?title=USB4&oldid=1347428772#USB4_Version_2.0 https://en.wikipedia.org/w/index.php?title=USB4&oldid=134742...
- stackghost 5mo agoThunderbolt 5 is basically just PCI Express, power delivery, and DisplayPort over the same cable, which for reasons passing understanding is terminated with a USB-C connector. I think most of those cables will also support USB the protocol.
- syhol 5mo ago- Thunderbolt 3 is a superset of USB 3.1 - USB4 is built on Thunderbolt 3's protocol, implementing a subset of its mandatory features - Thunderbolt 4 is a strict profile of USB4 (all optional features made mandatory) - USB4 v2 introduced 80 Gbps signaling - Thunderbolt 5 is a strict profile of USB4 v2 (again, optional features made mandatory)
- 15155 5mo agoGood sheet. Worth adding: - Female vs male crossover naming and pinouts for Type-C connectors - Actual voltage, modulation and signaling schemes (USB4v2 uses PAM3 11b/7t encoding) - PD generations and profiles
- mschuster91 5mo ago... and the bunch of proprietary voltage schemes like Quickcharge.
- retired 5mo agoThanks to the EU those are now forbidden, all phones and laptops should be compatible with USB-PD. Update: USB-PD is a requirement, but manufacturers are allowed to have their own proprietary charging solution.
- Neywiny 5mo agoI actually like the 3.2 naming. Gen is speed, "by" is width. It puts it very roughly on par with PCIe's naming which nobody complains about. I just don't like that USB 3, USB 3.1, and USB 3.2 are the same things. And that sales people don't seem to understand that saying a chip supports 3.1 or 3.2 tells me it's anywhere from 5-20gbps which isn't ideal.
- mistyvales 5mo agoPCI-E has had the same standard since its inception: 1.0, 2.0, 3.0, etc. USB has changed multiple times and has remained confusing for the vast majority of people. What was 3.0 is now not 3.0. Even 3.1 has changed. There is no reason to use this naming convention they currently have but for some reason they stick with it..
- Neywiny 5mo agoPossibly they stick with it because it's usable (ish) and it was driving everyone up the wall when they'd change it?
- kimixa 5mo agoPCIe also had things like "1.1", "2.1" and "3.1" - that fixed issues and added functionality - but there wasn't the same crossover between "feature sets and spec revisions" and "speeds" we see in USB today.
- mistyvales 5mo agoManufacturers of mainstream consumer motherboards never used 1.1, 2.1, etc. for PCI-E though. What is 4.0 on the spec sheet will be 4.0 to the buyer. My old 2016 motherboard has a slew of 3.0 labelled USB ports that are now not 3.0, hence the conundrum. It just doesn't make sense why they changed established naming conventions. Is this something that causes me sleepless nights? Not in the least. But it's still an annoyance for consumers and even advanced users as detailed in that latest Geerling video et al.
- DHowett 5mo agoExcellent article. If I could offer one correction, it would be that SBU (as specified by the USB 3.0 Promoter Group[1]) means "Sideband Use" rather than "Secondary Bus". On some devices, it is used to carry UART; on others, audio. [1]: https://www.usb.org/sites/default/files/USB%20Type-C%20Spec%20R2.0%20-%20August%202019.pdf https://www.usb.org/sites/default/files/USB%20Type-C%20Spec%... (pdf)
- altairprime 5mo agoTheir email address is under the Contact link in the header :)
- fabiensanglard 5mo agoThank you for taking the time to report the issue. It has now been addressed.
- DHowett 5mo agoOh wow, thank you!
- maxloh 5mo agoI once heard that the USB naming is misleading by design so that vendors could still sell older generations accessories they had in stock. The USB-IF just rebrands the old ones to make them sound current. Imagine the following naming: USB 3.0 / USB 3.1 Gen 1 / USB 3.2 Gen 1 -> USB 3 5Gbps USB 3.1 / USB 3.1 Gen 2 / USB 3.2 Gen 2 -> USB 3 10Gbps USB 3.2 Gen 2x2 -> USB 3 20Gbps Isn't that much clearer? I think USB 4 is finally going to the right direction.
- kubik369 5mo agoI think this practice is rather blatantly what you say. The same thing with HDMI forum folding HDMI 2.0 into HDMI 2.1. They made the new 2.1 features optional, therefore manufacturers were able to call their 2.0 devices 2.1 without actually supporting the 2.1 features. AMD has been recently doing similar things, releasing “new” generation of mobile processors where half of them are just rebrands of the older generation.
- xzjis 5mo agoOr it could be: 5 Gbps --> USB 3 10 Gbps --> USB 3.1 20 Gbps --> USB 3.2 Higher number = better
- sgjohnson 5mo ago> I think USB 4 is finally going to the right direction. USB 4 is actually going into an even worse direction. USB 4 = Thunderbolt 4, except everything is optional. e.g. USB 4 might not even support DP Alt mode. Thunderbolt 4 always will.
- brigade 5mo agoEven backwards compatibility is optional in USB4. There are USB4 devices (SSDs at least) that will not function when connected to USB 3 ports.
- privacyking 5mo agoThat’s not backwards compatibility
- naveed125 5mo agonice work, thanks
- 1a527dd5 5mo agoTangent: Author has this fabulous post I'd highly recommend: https://fabiensanglard.net/mjolnir/index.html https://fabiensanglard.net/mjolnir/index.html I read it once years ago and I come back to it every now and then wishing my current PC (10+ years and going) would gently die so I could finally build something small and tiny.
- fabiensanglard 5mo agoYou know, accidents happen. If you were to trip over the carpet and that venerable PC falls in the dumpster.
- vasvir 5mo agoThis sounds kinda premeditated though...
- thenthenthen 5mo agoMaybe walk back and forth a bit dragging your feet on said carpet and open your pc for ‘maintenance’ and accidentally fry some critical component?
- moffkalast 5mo agoAh that's where your wrong, see it's called Mjolnir. Only the worthy can move it. It's totally not because its density is probably close to lead given the concentration of parts in such a tiny space, with some rubber feat that thing ain't going nowhere.
- 1a527dd5 5mo agoHa! No chance, my case comes in at a beefy 18kg (purchased circa 2008). Some of the components are slowly starting to give up the ghost. My GPU purchased in 2011-03 died a few weeks ago. So it's happening, unfortunately I'm not paying for new RAM. So I'm planning a new rig around my existing CMK64GX4M4A2400C14 sticks.
- retired 5mo agoThe simplicity of Thunderbolt. Versions 1 and 2 used mini DisplayPort, 3 and upwards USB-C. Version 1 was 10Gbps, 2 was 20Gbps, 3 was 40Gbps, 4 was 40Gbps, 5 is 80 or 120Gbps with boosting. A Thunderbolt 5 cable will always support 80Gbps, DisplayPort 2.1, PCIe, USB4 and power of up to 240 watt.
- conception 5mo agoThis article is why I replaced all the usb dock cables in the office to make sure the usb cable connected to the laptops was transferring enough power so the laptop wouldn't silently lower its frequency for the lower power draw. 10-30% speed bump just because.
- drob518 5mo agoI’ve been a tech guy for 45 years and I still can’t figure out USB and Thunderbolt and what goes with what and how fast it’s supposed to run.
- 15155 5mo agoIf you buy Thunderbolt 5 cables: every USB standard is compatible and then some.
- ProllyInfamous 5mo agoIt wasn't until last year that I finally purchased my first USB-C device/cables – and after years of solid DisplayPort and Thunderbolt2 connections I absolutely hate USB-C (it's too delicate, physically). Not until 2023 did I even have a computer newer than 2012, so I missed almost all of USB3's hayday — including nomenclature disputes — but the speeds sure are an improvement!
- adrian_b 5mo agoWhile USB Type C can be broken much more easily by brute force and it is more prone to accidental disconnects than Type A, the Type C connectors are guaranteed to survive much more cycles of plugging/unplugging than Type A connectors. Type A connectors are typically guaranteed only for around 1000 cycles, with some better connectors rated up to 1500 cycles and some worse connectors rated only for a few hundred cycles. If you have a device with a Type A connector that you plug and unplug at least once per day, there is a non-negligible risk that the connector will become defective before other components of the device. On the other hand Type C connectors are guaranteed for at least ten thousand mating cycles, with the best guaranteed for at least twenty thousand cycles, so you should not be able to wear them out through normal usage. It is true however that you must handle Type C connectors much more delicately than Type A, otherwise you can break them before they are worn out by mating cycles. During the last few years, high-endurance Type A connectors have also appeared, which can survive a limit between 5 thousand and 20 thousand mating cycles, matching Type C connectors, but most equipment with Type A connectors does not use such more expensive connectors.
- pxeboot 5mo agoI still don't understand why MacBooks support USB4/Thunderbolt 4/5, but NOT USB 3.2 Gen 2x2. So you can get 20-40Gb/s speeds with more expensive external disks, but only 10Gb/s with the cheaper, more commonly available ones that advertise 20Gb/s.
- altairprime 5mo agoI believe it’s that MacBooks support Thunderbolt primarily and USB only where absolutely necessary beyond what’s coded into one of the TB specs; and I assume TB doesn’t define 3.2x2x2 as part of any TB spec <=5?
- aleksi1578 5mo ago[flagged]
- fl4regun 5mo agoYou need to relax buddy, it's just a post on a web forum, why are you so angry?
- _-_-__-_-_- 5mo agoDon't call him buddy, guy.
- phatskat 5mo agoDon’t call him guy, pal.
- userbinator 5mo agoIMHO USB 3.0 was the last sanely-named version. Then again, if you're familiar with Ethernet, the proliferation of variants isn't unexpected.
- offbyone42 5mo agoI just wish product listings were clear and actually followed the specs.
- dang 5mo agoRelated. Others? USB Cheat Sheet - https://news.ycombinator.com/item?id=31271038 https://news.ycombinator.com/item?id=31271038 - May 2022 (168 comments)
- floxy 5mo agoI don't know what short-distance data communications will be like in 2050, but we know it will be called USB.
- jasongill 5mo agoUSB-G 4.6 SuperSpeed Plus, but the cables will still just be used for charging your random electronics and won't even work for that half the time.
- SlightlyLeftPad 5mo ago…because Staples has replaced Amazon and Temu, which both went bankrupt in 2042, and all usb-c cables are made in Papua New Guinea with only 1/4 of the pins connected to wires. Some things never change.
- dotancohen 5mo agoI know not with what technology 2030 will use, but 2040 will use USB sticks and stones.
- wat10000 5mo agoWell, obviously. What do you think the U stands for? When we make contact with aliens, we’ll find them using it too.
- layer8 5mo agoI wouldn’t be too surprised if they rebrand to AI Bus.
- mrandish 5mo agoWait, really? Where can I invest?
- AdamH12113 5mo agoThis is generally good but it’s missing low speed (1.5 megabits/second), which is also under USB 1.1.
- mahirsaid 5mo agoGreat way of identifying the difference in types of USB
- Traubenfuchs 5mo agoWhy do we constantly change this? What technological advance was not available x years ago to dream up usb 4? We already know we will use the bandwith, why not dream up what will be the usb 8 spec in 20 years now and have everything working without change for 20 years?
- SyncOnGreen 5mo ago> SBU1 and SBU2 are secondary bus wires, for the DisplayPort AUX channel and hot plug detection (HPD). Correction - HPD signal is translated into vendor message and carried over CC lines - same ones that are used for PD and AltMode negotiation. In DP-Alt mode SBU1/2 basically becomes AUX+/-.
- esskay 5mo agoI'd love for someone who's part of the USB-IF to try and explain what the heck they were thinking with their naming conventions. They're indefensibly awful in every way.
- gblargg 5mo agoThe wires count is suspect. USB 1.0-2.0 only use two wires for data (the other two are ground and power). USB 3.0 uses 4 for data (plus extra shield, 2 for USB 2.0 and 2 for power). I don't know well enough the others.
- Liftyee 5mo agoThe wires count seems to be the number of conductors in the cable (i.e. the number of wires you'll find if you cut a cable in half, including ground and power). It's true that the actual data is sent over a lower number of diffpairs. I suspect the shield is not included in the number of wires, since all USB cables have a shield (not sure if usb 3.0 has an extra return ground wire for high speed).
- crote 5mo agoIt still would't be right. Full-featured USB-C has 8x superspeed (tx1p, tx1n, rx1p, rx1n, tx2p, tx2n, rx2p, rx2n), 2x high-speed (dp, dn), 2x power (vbus, gnd), 2x SBU, 1x CC. That's 15 wires.
- adrian_b 5mo agoA full-featured USB-C connector has 24 pins, as shown in a diagram in the parent article. The "12-wire" count of the parent article refers only to the main wires, i.e. the 4 USB 2.0 wires + 4 differential pairs for USB 3 or 4. Similarly, the "8-wire" count for Type A connectors refers only to the main wires, i.e. 4 USB 2.0 wires + 2 differential pairs for USB 3.
- crote 5mo agoYes, but not all of those 24 pins are used, and some of them are duplicated. I also don't think you can make this "main wire" distinction: you shouldn't be counting the power wires if you only care about USB data in the Type A case, and you should arguably be counting the CC wire in the Type C case if you want to go for "strictly necessary to function", or the SBU wires if you want to go for "carries data at nontrivial speeds".
- bombcar 5mo agoUSB 3.11 for Workgroups.
- nawi 5mo agothis is great, does usb cable has some limitation? can i take any length? i saw you measure 4m any advices longer cable?
- einpoklum 5mo agoI'm also wondering what the cable length figures in the cheat mean exactly.
- analog31 5mo agoI've tried longer cables on the slower USB's. My experience is that it can be touch and go depending on the peripheral. As I understand it, cable length is limited by the round-trip time between the host and the peripheral. Where I've had good and bad "luck" with USB cabling is video cameras, which require a fairly high bandwidth data stream.