Talk:USB/Archive 8

This is an archive of past discussions about USB. Do not edit the contents of this page. If you wish to start a new discussion or revive an old one, please do so on the current talk page.

Archive 5

Archive 6

Archive 7

Archive 8

Archive 9

Split history and USB3 sections

Agree - I agree that the article is too long and I think those two sections would work nicely in their own articles with a link back to small paragraphs here. § Music Sorter § (talk) 23:13, 23 June 2011 (UTC)

Done. Chris Cunningham (user:thumperward) - talk 08:12, 24 June 2011 (UTC)

Mice vs mouses

The mouse (computing) article covers this naming convention question with sources. You will find a number of sources saying it can be either mice or mouses and the official online Oxford Dictionary (2011) source states the term mice is more common. Since the mouse article uses mice throughout the article and this article was written originally with mice (from what I can tell), I propose that this article which links to that article use the same convention. I am reverting the change to keep the original until we come to a consensus. § Music Sorter § (talk) 05:21, 7 July 2011 (UTC)

Quite. "Mouses" is sheer pedantry, and I've never heard it in the wild. Chris Cunningham (user:thumperward) - talk 08:14, 7 July 2011 (UTC)

"Mice". Never ever heard or read "Mouses" which just sounds horrible. --Zac67 (talk) 16:27, 7 July 2011 (UTC)

There's no such thing as a consensus on grammar. It's "Mice". "Mouses" is only used when people are trying to be cute. Padillah (talk) 17:41, 7 July 2011 (UTC)

I've eliminated the controversy in the lead section by replacing "mice" with the general term "pointing devices", with a wikilink to [[Mouse (computing)]]. "Pointing devices" includes terms like mouse, trackball, touchpad, digitizing tablet, joystick, etc. — Quicksilver^{T @} 16:24, 13 July 2011 (UTC)

Lead too short?

Smackbot tagged the article with {{Lead too short}} on 1 July 2011. The lead could use some work to improve the article summary in the first sentence or two, removing some of the convoluted syntax and making it more accessible to a tyro, but I see nothing wrong with the length of the lead. Accordingly, I've removed the tag. — Quicksilver^{T @} 16:05, 13 July 2011 (UTC)

Smackbot merely dated the tag: I added it, as even after rewriting the old lede to better act as a summary it's still far, far too short for as well-developed an article as this. It does not make the most cursory effort to explain the technical details of the standard and brushes on its history and use in only the lightest manner. Please read WP:LEDE, which explains exactly what we expect of a good article introduction; for an article this size it should be three or four good paragraphs long and should make an adequate attempt to summarise all of the key points expressed in the article. If I don't find time to do this myself in the near future I'll be re-tagging it. Chris Cunningham (user:thumperward) - talk 13:46, 14 July 2011 (UTC)

Redirect request

Can an authorized user make a redirect from USB plugs to USB#Physical_appearance please?
~ender 2011-08-10 20:38:MST

Done Chris Cunningham (user:thumperward) - talk 13:38, 12 October 2011 (UTC)

System Design Section

This section is too theoretical with no examples provided for each new term introduced. The vast majority of people use USB devices, so giving examples of what each term means seems only natural. To not give examples only serves to keep the general public away from reading this section. — Preceding unsigned comment added by 69.113.81.244 (talk) 01:06, 18 September 2011 (UTC)

USB.org links

Seanmcd27 (talk · contribs) added the following comment to the references section while fixing some dead references. It doesn't belong in the article body so I've moved it here.

note that because of the naming convention used by the usb consortium website, every time they update a document it breaks the links on this page. if you go to [1] you can find the documents referenced on this page even if the more specific links are broken

Chris Cunningham (user:thumperward) - talk 23:03, 15 October 2011 (UTC)

Controversy

Some people say the logo which is similar to a pitchfork was created to offend Christians --88.111.125.135 (talk) 21:20, 11 December 2011 (UTC)

Who are those people?.Jasper Deng (talk) 21:27, 11 December 2011 (UTC)

The key word to search for is "trident". If you Google "trident USB Christians", there are an abundant of articles that can serve as possible sources. The trident is seen as a symbol of Satan, and USB's use of an image of a trident has some Christians to refer to USB devices as "satanic devices," or "the devil's technology." If you look in the Trident in popular culture article, you'll find a mention of the USB symbol looking like a trident. As a result, Evangelical Christians in Brazil, for example, have banned the use of USB after claiming the technology is the mark of Satan-worshippers. If Wikipedia allows discussions of "fan death" among the Koreans, I think the trident link is well sourced and should be covered, if anything, as a pop culture subject. Groink (talk) 22:46, 11 December 2011 (UTC)

There's nothing to suggest that it was created with the purpose of that.Jasper Deng (talk) 22:57, 11 December 2011 (UTC)

No no, no one saying that the USB trident was used "for" the purpose of symbolizing Satan, although the original editor mentioned as such. Think of the issue when Procter & Gamble used a moon like symbol for its corporate logo, and people believed that the company were Satan worshipers. This is well covered in the Wikipedia article, under the "Logo controversy" section. Many articles here in Wikipedia cover these kinds of issues regarding logos; Google "site:en.wiki.x.io satan logo" Groink (talk) 23:07, 11 December 2011 (UTC)

The original story came from a Brazilian newspaper equivalent of the Onion, translated to English, reprinted, and then taken out of context and ran as truth. It doesn't matter how many RS re-ran, quoted, paraphrased the story when the source was satire. SchmuckyTheCat (talk)

This should NEVER be taken seriously, otherwise it turns into this mess: Moon landing conspiracy theories. If you create a section in the article, put it at the bottom and call it Humor or something not serious sounding, because it sure the heck isn't a real controversy. • Sbmeirow • Talk • 23:56, 11 December 2011 (UTC)

We're not going to add a new section for something so trivial. If this were a genuinely notable event (which it isn't, as detailed by SchmuckyTheCat above) then it would belong in the still-to-be-written section on the standard's impact. However, as it isn't, it doesn't. Chris Cunningham (user:thumperward) (talk) 10:59, 12 December 2011 (UTC)

Requested move 2012

The following discussion is an archived discussion of a requested move. Please do not modify it. Subsequent comments should be made in a new section on the talk page. No further edits should be made to this section.

The result of the move request was: page moved. Vegaswikian (talk) 03:52, 21 January 2012 (UTC)

USB → Universal Serial Bus – The reasons for this request are based on the dispute over the legitimacy of the move last June and the discussion. I deliberately didn't want to propose this over Christmas when people are less likely to be paying attention and while this is far from my preferred approach (I would rather the original decision was overturned) it does seem the best way of getting a shoddy decision reversed based on the advice given at dispute resolution.

There are four primary reasons for proposing this move:

There was no consensus for the previous move.
The determination of consensus was based on a selective application of policy and no opportunity was given to dispute that.
WP:TITLEFORMAT is clear that there is a presumption against initialisms in article titles.
The threshold for over-riding that presumption where the subject is "almost exclusively" known by its initialism and an expanded form is less familiar that the abbreviated form. That does not apply here.

I'm aware people may be getting tired of this by now, but it was a outrageous decision then and it still is now. Hopefully we can draw a line under this with a fresh discussion. Crispmuncher (talk) 04:08, 14 January 2012 (UTC).

Support. Have a look at USB (disambiguation), there are several important competitors for the acronym. Of course web-based searches will currently favour the computer term, but Universal Serial Bus is recognizable to readers, unambiguous, and consistent with usage in reliable English-language sources (WP:AT of course) while the acronym is arguably ambiguous. Play safe and make the undisambiguated name USB the DAB. Andrewa (talk) 05:01, 14 January 2012 (UTC)
Oppose. Very few non-technical people know what the full term means, or even that the "bus" in question is a Bus (computing), not a Bus (that universally follows a series of stops ;-). Everybody knows that "USB" is something the mouse or the harddrive needs to work with his computer. The other USBs are, without exception, abbreviations only encountered in very specialised situations. Even if I heard about e.g. a "USB report" in an academic situation, I would expect a report about USB, not a report written by Stony Brook or the Universidad Simón Bolívar. --Stephan Schulz (talk) 12:35, 14 January 2012 (UTC)
- Comment: That has not been my experience, or I suppose it depends what you mean by non-technical people... very few Australians, and almost none below the age of thirty, are uncomfortable programming and using a GPS or downloading pictures from a mobile phone. In that sense even those who describe themselves as non-technical are actually far more technically competent than the majority of Australians were in my youth. The phrase universal serial bus flows off the tongue without any thought that it might a sort of motor omnibus, any more than the phrase Her Majesty the Queen leads them to wonder whether the current monarch is best described as Majestic. The case might be stronger in the case of LED; I doubt even technical people would object to using the term for a three-lead device were one to come into common use, it would no longer be any sort of diode but would IMO still be called a LED for clarity. And yet we still use Light-emitting diode rather than LED as the article title. Andrewa (talk) 16:33, 14 January 2012 (UTC)
Weak support because of WP:TITLEFORMAT. USB should still redirect. SchmuckyTheCat (talk)

Weak support per SchmuckyTheCat, including redirect. This initialism thing easily gets out of control with vested interests jockeying for perceived status in obscurity. This case is close, IMO, because this meaning seems used much more often than the dozen others, but better to err on the side of clarity and description rather than jargon and insider knowledge. ENeville (talk) 21:03, 14 January 2012 (UTC)
Support per WP:TITLEFORMAT, with USB as prime redirect. The rest routing to USB (disambiguation). -- SchreyP ^(messages) 21:10, 14 January 2012 (UTC)
Strong oppose. There seems to be a concession here that this is the primary topic for USB, so I won't argue for that. But given that it's the primary topic, why not use the more recognizable form? WP:COMMONNAME seems clear on this point. Powers ^T 03:01, 16 January 2012 (UTC)

The provision of WP:TITLEFORMAT relating to initialisms takes precedence since it is much more specific than the more general guidance at WP:COMMONNAME. In any case I have not accepted USB is the more common name in reliable sources: its simply that at dispute resolution both sides accepted we don't need to show the full form is more common. Crispmuncher (talk) 15:27, 16 January 2012 (UTC).

TITLEFORMAT only specifies a presumption in favor of the expanded title; in the case of a widely known acronym such as this one, one which is regularly used without expansion in reliable sources, the presumption is no longer necessary and gets in the way of serving our readers. Powers ^T 19:32, 16 January 2012 (UTC)

Widespread use is not the threshold for countermanding that presumption: almost exclusive use is. That is difficult to demonstrate as evidenced by previous discussions of the issue. Crispmuncher (talk) 20:14, 16 January 2012 (UTC).

If it's that difficult to demonstrate, then the threshold is too high. Powers ^T 21:21, 16 January 2012 (UTC)

Weak oppose - at first I wanted to support, but I changed my mind after reading WP:ACRONYMTITLE: almost exclusively known by its acronym or is widely known and used in that form (e.g. NASA and radar). and also: In many cases, no decision is necessary because a given acronym has several expansions, none of which is the most prominent. [...] the acronym should be a disambiguation page. Han-Kwang (t) 17:23, 16 January 2012 (UTC)
Oppose per WP:ACRONYMTITLE. — MrDolomite • Talk 23:12, 16 January 2012 (UTC)
Weak support We should avoid acronyms in titles if the subject of the article has a widely known expanded form. It is indeed widely known to computer enthusiasts that USB stands for "Universal Serial Bus". A strong counter-argument would be that the less digitally literate have only encountered this name in compound terms, primarily the now ubiquitous "USB stick". Having a redirect from USB to Universal Serial Bus, instead of to a disambiguation page, would remedy any associated problems with this, however. —Ruud 20:22, 17 January 2012 (UTC)
Support. Frankly I don't see how anyone can "oppose per WP:TITLEFORMAT" or equivalent, at least without a lot of elaboration. Those policy statements are clear that there is a presumption AGAINST acronyms. The exception clearly has a very high threshold by design and I don't see this meeting that. Even Powers above doesn't claim this, criticizing the policy rather than its application. The title is very much part of the article too and I feel that "Universal Serial Bus" better communicates what the article is about than yet another TLA. Quantumsilverfish (talk) 03:59, 18 January 2012 (UTC)
- Please don't put words in my mouth. I support TITLEFORMAT's advice in general; I just think it's being applied too strictly here. As Han-Kwang said, ACRONYMTITLE allows initialisms if the subject "is widely known and used in that form". That's clearly the case here, and if WP:TITLEFORMAT doesn't include that same language, it should. Powers ^T 14:35, 19 January 2012 (UTC)
  - Sorry, that was not my intention, but the threshold is intentionally set high in policy. It is not a question of interpretation and application. Quantumsilverfish (talk) 15:01, 20 January 2012 (UTC).
Comment. Interestingly, a few months ago at Wikipedia talk:Article titles#Weakening the wording of WP:ACRONYMTITLE there was almost universal agreement that USB was clearly allowed under ACRONYMTITLE because it is so common. Jenks24 (talk) 06:34, 19 January 2012 (UTC)

It is not a given where consensus is there, certainly not overwhelmingly so: it starts out strongly for USB but swings back towards the end. In any case I will point out it is not a balanced discussion: I chose not to take part, nor did any other opposers of the disputed move. In my case the whole discussion left a very bad taste in the mouth: after being accused of forum shopping simply for filing a case at DR after months of being ignored that very editor opens up a new front days later. It's worth also noting the case at DR[2] since even neutral commentators raised concerns as to the legitimacy of the previous move. That becomes especially significant in case of a "no consensus" outcome. Crispmuncher (talk) 01:52, 20 January 2012 (UTC).

The above discussion is preserved as an archive of a requested move. Please do not modify it. Subsequent comments should be made in a new section on this talk page. No further edits should be made to this section.

4-pin Mini B USB connector?

Is there any information in the article about a 4-pin mini B connector, as opposed to the 5-pin version? Apologies if I've missed it - Or maybe it's not a USB standard, it's just some people have bought a Mini-B cable that doesn't fit, ie - You need to know the pin number also. Thanks 88.104.143.197 (talk) 19:24, 24 January 2012 (UTC)

Host interface receptacles diagrams wrong

the plug and socket images are the same for most of them, they need to be changed so the pin numbering is reversed on the plug, and so the image is of a plug connector not a socket.--82.4.97.209 (talk) 12:23, 2 April 2012 (UTC)

Actually, it seems now to be just the Type A and Type B receptacles that erroneously show diagrams of connectors. In addition to flipping the pin numbers, they should also be modified to correctly show solid areas and open areas as the reverse of what they would be for their corresponding connectors. Quick check did not show such diagrams currently in Commons.Areinarz (talk) 00:45, 4 December 2012 (UTC)

400px-Usb_connectors.JPG / "a non-USB proprietary plug"

The caption on 400px-Usb_connectors.JPG seems incorrect or minimally ambiguous as it relates to the wording "a non-USB proprietary plug" "Types of USB connectors left to right (ruler in centimeters): Micro-B plug, a non-USB proprietary plug, Mini-B plug (5-pin), Standard-A receptacle, Standard-A plug, Standard-B plug"

I propose: "a proprietary plug" instead of "a non-USB proprietary plug". For most people "proprietary" denotes a lack of interoperability. So non and "proprietary" together sounds like it is universal. Is that the case with this plug? Semantics could be argued, regardless it is confusing.

--170.252.248.203 (talk) 19:53, 5 April 2012 (UTC)

Supported - 'non-USB' is misleading as it's obviously using USB (or isn't it?) but in a non-standard, non-canonical form factor. Zac67 (talk) 16:51, 6 April 2012 (UTC)

High Power from Apple Computers

According to http://support.apple.com/kb/HT4049, newer Apple computers have USB ports that can supply 12V at 1100mA. I don't have any information on how a device can request this power; it would be great if someone who knows how to do this would put it in this article. SomeDwayne (talk) 15:47, 9 April 2012 (UTC)

I can only see mention of 5V at 1100mA. --Petteri Aimonen (talk) 19:54, 16 April 2012 (UTC)

Y-cable not mandatory

I have usually had no problems with those slightly higher-power USB devices when used with a straight cable (instead of the Y-cable that ships with them). I'm talking about 2.5" HDDs and slim-type optical drives. Is it that the USB controller does not actually care and the power is just delivered directly from the 5V rail? So maybe the Power section should also mention that in practice many times those devices work without having to pull power from 2 ports? 84.248.91.142 (talk) 15:56, 29 April 2012 (UTC)

Loading a 2.0 USB port with >500 mA violates the standard. It may or may not work and some (esp. notebook) ports may even get destroyed, so advising to neglect the standard is bad advice. Y-cables are non-standard as well and may or may not work and/or destroy a port. I agree that in 99.9% of all cases this doesn't matter but have also seen notebooks go up in smoke. IMHO it's a bad idea supplying >50 mA or 100 mA to a port that hasn't properly arbitrated for more to begin with. OTOH a maximum of 2.5 W was very weak from the start - 1394 allows up to 45 W. Zac67 (talk) 19:49, 29 April 2012 (UTC)

Actually if any damge results that is itself a violation of the standard - the lines (both data and power) must be short-circuit proof and must re-enable once the condition is removed (I admit I can't recall immediately whether a device reset is permitted, but e.g. a push-to-reset circuit breaker isn't). The spec permits up to 100mA without any negotiation at all - this isn't sloppy but essential even for "full" USB devices as opposed to power thieves: many devices require start-up time before they can declare themselves and begin the enumeration process. As for the excess current, most motherboards ultimately limit current through use of a polyfuse. Whether that is one fuse per port, or one per number of ports varies depending both on the manufacturer and the model. A 1A fuse common to a pair of ports is quite common. Crispmuncher (talk) 21:15, 29 April 2012 (UTC).

WP is not in the advice business, nor here to promulgate any offical viewpoint. We are here to describe and dispense relevant details. The USB power situation is complicated, and needs to be worded with care. (Many external hubs are power-challenged. Even when sold with power supplies, they are often under-powered.) -96.233.20.116 (talk) 21:23, 1 June 2012 (UTC)

USB/AV out

There is devices (digital cameras, phones) which has USB to audio/video output. The USB to AV output cable has RCA connector on other side. This is very interesting and not obvious usage of USB. I think USB/AV out should be explained in this article (at least it should be mentioned). — Preceding unsigned comment added by 46.118.216.195 (talk) 19:00, 10 May 2012 (UTC)

USB On-The-Go Connectors, correct?

In this article under the heading: USB On-The-Go Connectors "A USB On-The-Go device is required to have one, and only one USB connector: a Mini-AB or Micro-AB receptacle" ... Propose this is better as per the USB To Go article to have: "The original USB On-The-Go standard introduced a plug receptacle called mini-AB which was replaced by the micro-AB in later revisions (Revision 1.4 onwards)."

Wikiacc101px9 (talk) 11:34, 9 July 2012 (UTC)

Sounds reasonable. --Frederico1234 (talk) 11:53, 30 July 2012 (UTC)

Plus symbol on USB logos

I came here looking for the meaning of the plus symbol on the USB logo on many USB ports, surprisingly it is not mentioned.

I propose to change the logo to something like http://galaxy4.net/misc/USB_Icon_with_plus.svg and make the description read "The basic USB trident logo, showing optional plus symbol representing USB 2.0 support [#]' citing reference "USB 2.0 Icon Design Guideline" at http://www.usb.org/developers/docs. — Preceding unsigned comment added by Annihilannic (talk • contribs) 11:30, 30 July 2012 (UTC)

Actually now I'm leaning more towards an image with the 3 logo variants (including the SS "superspeed" version for USB 3.0) one above the other. --Annihilannic (talk) 03:10, 11 August 2012 (UTC)

simultaneous charge and sync

>To support simultaneous charge and sync, even if the communication port doesn't support charging a demanding device, so called accessory charging adapters are introduced, where a charging port and a communication port can be combined into a single port.

Could this be explained in more details?

85.115.110.103 (talk) 13:56, 16 September 2012 (UTC)

A/B Power

Section "Usability and "upside down" connectors" The standard connectors were deliberately intended to enforce the directed topology of a USB network: type A connectors on host devices that supply power and type B connectors on target devices that receive power

Section "USB standard connectors" "A Type B plug delivers power in addition to carrying data"

Something is wrong here. — Preceding unsigned comment added by Mtpaley (talk • contribs) 21:04, 25 September 2012 (UTC)

Perhaps the author means that the Type B plug delivers power (from the A end of the cable) to the Type B receptacle. Although, come to think of it, the first sentence above would probably be more correct if it said: ... Type A receptacles on host devices that supply power and Type B receptacles on target devices that receive power. Areinarz (talk) 00:53, 4 December 2012 (UTC)

Conflicting Data

"USB 2.0: Released in April 2000. Added higher maximum signaling rate of 480 Mbit/s (effective throughput up to 35 MB/s)"

"USB 3.0 was released in November 2008. The standard specifies a maximum transmission speed of up to 5 Gbit/s (625 MB/s), which is more than 10 times as fast as USB 2.0 (480 Mbit/s, or 60 MB/s)"

so which is it, 35 MB/s or 60 MB/s? Freegen (talk) 05:20, 20 October 2012 (UTC)

480 MBit/s divided by 8 gives 60 MByte/s. pcuser42 (talk) 06:39, 20 October 2012 (UTC)

Effective throughput is always smaller than the maximum transmission speed, because of protocol overhead. Later in the same paragraph there is info on the effective throughput of USB 3.0 (estimated at 400 MB/s). --Petteri Aimonen (talk) 09:33, 20 October 2012 (UTC)

Nokia picture?

Why is that Nokia Pop-port picture where it is?

There's nothing in that area about Nokia. Later, the article mentions Nokia; does it need to be moved there?

Fustigate314159 (talk) 17:29, 1 November 2012 (UTC)

Request for approval to translate this article to Ukrainian Wikipedia

Hi, Thanks to all the editors of this page. for their hard work and time spent. I have read the Help pages but I found very little about translation of Wikipedia articles between different language versions, other than citing the original article at the heading. I 'd like to ask the editors how they would feel about me translating their article to the Ukrainian version of Wikipedia? My Other Head (talk) 11:17, 15 November 2012 (UTC)

A mess

Quite frankly this article to me feels like a complete mess! Please don't take this as an insult to the authors because it's not. This article has loads of great information for a very important topic. THat being said I think it suffers heavily from a lack of design. All of this information causes it to feel very overwhelming and disorganized in the way it is presented. For example, I think its a great idea to have the versions of USB at the beginning of this article where they are located. People will often come to this article trying to find the difference between the USB2.0 and USB3.0, having this at the beginning is perfect. The problem is the USB2.0 section looks like it threw up on itself. There is NO NEED to have that list at this place in the article. Are many of them important? Yes. Do they need to be there? Definitely not. They would likely be better addressed at other points in the article or not at all.

Additionally, the history is good but I feel that the history section might be better organized allowing it to serve as both a history AND a quick reference at the same time. By splitting the USB2.0 paragraph and putting it in the following USB2.0 section and same with the USB 3.0 paragraph. I propose that each of the version subsections contain the following: Short history blurb(likely address why the version was created), number of pins, Dataspeeds (low and high), power capabilities, does it have additional charge capabilities (and if so whats the usual max power capability). This would let people know the most relevant information in a quick nutshell. Then as the article goes on you can get into the nitty gritty like signaling protocols, plug variants, etc.

Just my thoughts.

PedroDaGr8 (talk) 06:21, 20 December 2012 (UTC)

I agree wholeheartedly! The problem with many techie articles like this one is that most contributors are techies themselves. And I've learned from years of software and hardware development experience that techies write terrible documentation. It basically takes someone with virtually no knowledge of the subject to really clean things up here. What you and I would consider useless, techies consider vitally important to record complete detailed descriptions of every little thing to do with USB.

With that said, what needs to be done to this article is to restructure the sections so that at least the first page of the article displays what most people will want to read, and the second half being all the technical detailed stuff. Many people visit this article not for the gory details about USB, but rather the basics about connectors, cross-compatibility, and operating system support. Studies have shown that people will only read the first "page" of a Wikipedia page, and not even bother to scroll down. Therefore, it is vitally important that the basics of USB are covered on the first page. Maybe even utilize collapsible tables of the really techie stuff to shorten the display length of the article to make it easier to read. That's how I'd approach a re-org. Groink (talk) 06:59, 20 December 2012 (UTC)

I completely agree I am working on restructuring the beginning. I think in general the article should flow:

Intro - always necessary
History/Versions/Overview - This will be the tl;dr section of the article. I feel should include the who, what, when and why about USB. It also should have a standardized layout/table that lists the logo, the name, high/low speeds, current capabilities, battery charge ability, etc.
Physical Features - This will discuss the physical features of USB.
A sub-topic of physical features: Connectors (Std A&B, Mini, Micro, USB 3.0, proprietary, etc.)
A sub-topic of physical features: Cabling
Power delivery capability (this could also theoretically be moved into the more technical area)
layers on top of the standard (such as Charger Mode and USB OTG)
After this is discussed NOW we can start getting into the technical stuff. Some of the stuff is very necessary (signalling and device types), a lot of the stuff feels like it needs to be consolidated into a few more logical sections, whileother stuff just feels like extra data.

PedroDaGr8 (talk) 21:58, 20 December 2012 (UTC)

Connectors and plugs - Usability and orientation: misleading/biased information

The section "Connectors and plugs" starts with a box reading: "Please help improve it by merging similar text or removing repeated statements". I'm tempted to take this advice advice and remove the word "incorrectly" from the sentence starting the subsection named "Usability and orientation" ;-) Jokes aside, the section really is lacking a lot of arguments. The main problem with the design is in the word "visible". I.e. To match a USB plug and a receptacle both of them must be visible, which is not easily achieved in most situations. The only use case where the USB plug design matches its expectations probably is, when you connect the plug at the end of a cable into a receptacle located at the end of another cable under good lighting conditions and without visual impairments preventing you from detecting the logo. In general the USB plug design fails to provide a reliable method for mating when you

are sitting at a table and insert a plug into a PC standing below the tabletop
insert a plug into a receptacle located at the back of a PC (traditionally the most common location)
insert a plug into a laptop computer without turning it around or bending your head over
are farsighted and don't wear your glasses
try to connect a device under low light conditions, esp. in combination with low vision

The Micro USB plugs found on mobile devices are even worse, if you don't have optimal vision. Fortunately, the problem can be worked around rather easily by applying a drop of hotmelt glue or some such on top of the logo on the USB plugs, improving their tactile recognizability. But such a barrier-free design should have been in the specs from the very start - and these problems should be mentioned in the discussion of the plug design in the WP article as well. BerlinSight (talk) 02:45, 9 December 2014 (UTC)

Hello! Well, that's already addressed in the USB § Usability and orientation section, here's a quote:

While it would have been better for usability if the cable could be plugged in with either side up, the original design left this out to make manufacturing as inexpensive as possible. Ajay Bhatt, who was involved in the original USB design team, is working on a new design to make the cable insertable either side up. The new reversible plug is also much smaller than the current USB 3.0 Micro-B connector; it is called Type-C, and should be introduced as an addition to the existing USB 3.1 specification.

That explains the reasons for such a design, and the future solution. — Dsimic (talk | contribs) 09:04, 9 December 2014 (UTC)

Sorry, no! Though the introduction of the Type-C plug actually would solve the problem, the qouted section does not address the problems I mentioned in any way. Also the argument "as inexpesive as possible" does not apply in that context. E.g. extruding the logo by some tenths of a millimeter does not significantly increase production costs. As I mentioned, the real problem is that the USB specs focus on the visibility of the logo, which, as I pointed out above, is a severly flawed design. BerlinSight (talk) 04:18, 10 December 2014 (UTC)

Some people have higher tactile sensitivity, some have lower; thus, it might be that raising the logo on USB plugs even slightly further might not help all people. However, manufacturers many times do not keep the USB sockets oriented in the right way, rendering the tactile feedback pretty much useless. I've seen numerous devices with wrongly oriented horizontal USB sockets, computer motherboards have their USB sockets in vertical position, for example, and not all ATX cases have the motherboards oriented the common way. Furthermore, people position devices they own differently, upside-down and whatnot. :) At the same time, Wikipedia is all about summing up reliable sources, not about publishing original research. — Dsimic (talk | contribs) 04:57, 10 December 2014 (UTC)

Micro-USB reliability

I saw articles tracing back Micro-USB reliability issues to its poor design. For example, Andreas Ødegård (2012-12-20). "Hardware comparison: Lightning connector vs MicroUSB connector". favoured double-sided Apple Lightning design over the "standard" micro-USB one.ilgiz (talk) 02:19, 10 December 2014 (UTC)

Hello! Right, Micro USB connectors aren't perfect and do have their own issues. Such design choices probably have origins in overall tendency to keep the cost low, and some associated inertia against redoing things from scratch. — Dsimic (talk | contribs) 06:11, 10 December 2014 (UTC)

Style on micro and mini USB

The capitalization for micro and mini is inconsistent. We should confirm which is correct and normalize. The USB Implementers Forum (at USB.org) seems to capitalize Micro uniformly, but I cannot find an instance of Mini to check. FelioLBB (talk) 22:35, 16 January 2015 (UTC)

Version history - USB 2.0: misleading information about bitrate

The section claims that "Due to bus access constraints, the effective throughput of the High Speed signaling rate is limited to 35 MB/s or 280 Mbit/s." and has a source (a table p.40 of the specification) to back it up. The editor failed to realize or convey that this is only the case for control transfers. On page 53 of the source, an equivalent table, show speeds closer to the previous figure of 480 MBit/s for bulk transfers which are used when transferring files. The same is also true of isochronous and interrupt transfers. Given this, and the fact that the section is not a proper place to distinguish between transfer types, I'm tempted to just remove the sentence. — Preceding unsigned comment added by 188.130.74.35 (talk) 15:00, 30 January 2015 (UTC)

Hello! I'm sure you've tried to use a fast USB flash drive over USB 2.0, and for some reason it can hardly go over those 35–40 MB/s. How should that be explained? — Dsimic (talk | contribs) 15:10, 30 January 2015 (UTC)

Actually, the article is not correct with "due to bus access constraints": it's the mass storage protocol/class that is flawed not (that much) the transport protocol itself, UAS is somewhat faster. WP:RS anyone? -- Zac67 (talk) 18:29, 30 January 2015 (UTC)

This one could be used as an overview of various restrictions; though, it's based on USB 1.0. — Dsimic (talk | contribs) 18:57, 30 January 2015 (UTC)

Linux kernel documentation claims that rates above 35MB/s are indeed achievable for bulk transfer and periodic transfer modes.— Preceding unsigned comment added by 2a01:e35:2427:8bc0:922b:34ff:fe92:7487 (talk) 21:36, 31 January 2015‎ (UTC)

That's a WP:RS for sure, but here's a quote from Documentation/usb/ehci.txt:

At this writing, individual USB 2.0 devices tend to max out at around 20 MByte/sec transfer rates. This is of course subject to change; and some devices now go faster, while others go slower.

The first NEC implementation of EHCI seems to have a hardware bottleneck at around 28 MByte/sec aggregate transfer rate. While this is clearly enough for a single device at 20 MByte/sec, putting three such devices onto one bus does not get you 60 MByte/sec. The issue appears to be that the controller hardware won't do concurrent USB and PCI access, so that it's only trying six (or maybe seven) USB transactions each microframe rather than thirteen. [...]

It's expected that newer implementations will better this, throwing more silicon real estate at the problem so that new motherboard chip sets will get closer to that 60 MByte/sec target. That includes an updated implementation from NEC, as well as other vendors' silicon.

Thus, unfortunately it confirms nothing about real-world USB 2.0 transfer rates higher than, as stated, 28 MB/s. At the same time, I still haven't seen a USB 2.0 controller that would go over those 35–40 MB/s with a fast USB flash drive. — Dsimic (talk | contribs) 21:58, 31 January 2015 (UTC)

eSATA information

"eSATA does not supply power to external devices." This is incorrect, I know this first hand since I have external eSATA 2.5" HDD. The data and the power goes through my eSATA port. Spiralciric (talk) 18:59, 13 March 2015 (UTC)

eSATA does not supply power to devices as SATA ports are not capable of this. eSATAp (which includes USB) does. pcuser42 (talk) 19:43, 13 March 2015 (UTC)

Max. voltage spec seems wrong

In the summary table under "Electrical", it says: "Max. voltage 5.00±0.25 V (pre-3.0)..." Does this mean that some models have a max. voltage of 4.75 V and other models a max. voltage of 5.25 V? Or does it mean that the max. voltage varies from unit to unit, so that one should always be at 4.75 V or below to prevent damage in the worst case? Either way it makes no sense. 173.76.253.219 (talk) 02:43, 14 March 2015 (UTC)

The standard says that devices should accept host voltages from the mentioned range. So "max." is probably not a good term. --Bdijkstra (talk) 17:40, 14 March 2015 (UTC)

5 volts, with a tolerance of 0.25 volts in either direction. pcuser42 (talk) 18:16, 14 March 2015 (UTC)

Well, "max. voltage" is what's presented by the {{Infobox connector}} template. In case of USB, presenting that as "operating voltage", for example, might be better, however opinions about that should be expressed on Template talk:Infobox connector. — Dsimic (talk | contribs) 09:02, 17 March 2015 (UTC)

Apparently it would be more correct to refer to it as the "nominal voltage" rather than the max voltage. See Real versus nominal value. -- DMahalko (talk) 10:44, 17 March 2015 (UTC)

USB 3.1 and Type-C

The text of the USB 3.1 Specification has been released on December 13, along with USB Power Delivery 2.0 and Type-C connector specifications. http://www.usb.org/developers/docs/ --37.144.226.124 (talk) 12:20, 28 December 2014 (UTC)

I concur the article needs amplification in this area, as well as a re-write of the existing content.20:54, 26 March 2015 (UTC) — Preceding unsigned comment added by 75.70.164.249 (talk)

USB 3.1 with Type A connectors

I don't know if this is allowed by the standard, but actually most current motherboards with USB 3.1 use the Type A connector, e.g. [3] [4] (the first link contains a photo of the plug, for the board in the second link, you can scroll down to see a photo of the board where connectors are marked). --MrBurns (talk) 14:22, 17 March 2015 (UTC)

I just added a remark, that some boards still use the type-A connector for USB 3.1. --MrBurns (talk) 14:32, 18 March 2015 (UTC)

-- I just added a comment to the USB Type-C section asking why the comment about USB 3.1 Type-A connectors is part of Type-C. I strongly concur that the Type-C section needs more expansion. And concur that 3.0/3.1 be merged and clarified as part of the overall USB wiki article. — Preceding unsigned comment added by 74.197.168.153 (talk) 18:40, 24 May 2015 (UTC)

Micro-B USB 3.0 plug pin-out

The Micro-B USB 3.0 pin-out looks incorrect. I believe that is the one for the 3.0 type-A or type-B connector. The Micro-B should be:

Power (VBUS)
USB 2.0 data− (D−)
USB 2.0 data+ (D+)
ID
GND
USB 3.0 transmit− (SSTx−)
USB 3.0 transmit+ (SSTx+)
GND_DRAIN
USB 3.0 receive− (SSRx−)
USB 3.0 receive+ (SSRx+) — Preceding unsigned comment added by 209.243.13.74 (talk) 15:55, 11 May 2015 (UTC)

The above diagram matches Figure 9. Schematic (2 of 3) on page 8 of the Texas Instruments User's Guide for HD3SS460EVM-SRC Evaluation Module Document# SLLU214A–February 2015–Revised March 2014. "The HD3SS460 is a high-speed passive crosspoint switch designed to support low- and high-speed signal switching required for Type C, with Alternate mode applications." The module includes a micro-B USB 3.0 receptacle for USB signal input from the Host as well as a DisplayPort receptacle for graphics input for transport via USB Type-C cabling. ^[1] — Preceding unsigned comment added by 74.197.168.153 (talk) 18:57, 24 May 2015 (UTC)

References

^ http://www.ti.com/lit/pdf/sllu214

Merge from USB 3.0 and restructuring

The connectors and plugs section of the USB article has become an incomprehensible mess, and having a dedicated section on USB3 only makes things worse, as it contains a similar incomprehensible mess forked into a separate article.

My proposal is to restructure the following sections: Overview, History, Connectors, Plugs and Cabling, Signaling, and Transmission rates, and make them into four major sections tentatively named:

Versions of the standard - should only list basic features and hardware requirements in each major version (1.1, 2.0, 3.0, 3.1)
History - dates of major announcements and standard
Connectors and cables - description of pinouts, connectors and cables and typical usage cases for end users; please remove incomprehensible "connection matrix" diagrams
Transfer modes - detailed description of bus specs and transfer speeds, including signaling protocols

But the first step is to merge content from USB 3.0 so the main article has a complete coverage of all versions.--93.80.58.33 (talk) 17:27, 14 January 2015 (UTC)

Hello! I'm yet to review recent changes to the USB and USB 3.0 articles. However, per WP:LENGTH and WP:SIZESPLIT, an article as long as USB shouldn't be receiving more content through article mergers. — Dsimic (talk | contribs) 15:05, 17 January 2015 (UTC)

Agree with Dsimic, and I believe it's OK for USB 3.0 to have a separate article as the technology used is kind of new and advanced. While it still falls under USB technology it's better to keep it this way rather than adding more content to USB.--Chamith (talk) 10:15, 28 January 2015 (UTC)

USB Type-C should probably get its own article as well, as right now it is very poorly explained here. 64.231.205.67 (talk) 13:34, 16 February 2015 (UTC)

Makes sense, and taking that route would also conform to the WP:SIZESPLIT guideline. — Dsimic (talk | contribs) 17:00, 16 February 2015 (UTC)

Related: shouldn't USB 3.1 be in the USB 3 article? It's a lot of content and would make more sense there, than back in the USB article. —ajf (talk) 12:28, 12 March 2015 (UTC)

im thinking hard here. all the USB articles need to be merged ALL OF THEM. the content needs to be then restructured in concise sections and split off as required. right now most of the new information about usb3, usb3.1 and USBC (usb type-c) are not reflected in the main article. HISTORY OF USB could be an article. TECHNICAL SPECIFICATIONS OF USB could be an article. everything else is fluff. 121.72.250.35 (talk) 22:31, 16 March 2015 (UTC)

There's no point in merging everything together just to make a "better" split between multiple articles. — Dsimic (talk | contribs) 08:54, 17 March 2015 (UTC)

I strongly concur with the proposed restructuring of sections and merging 3.0/3.1 articles into USB. I strongly disagree with the users above who claim these articles require their own pages. That's not the way Encyclopedia articles are written. Minor updates to a collection of strongly-related articles like USB should never have been written in their own pages in the first place, but rather, simply created another new section of the overarching USB article. Even major updates should be maintained on the same page, as they're all essentially revisions of the same technology: USB. Even if we wind up with a 1 Tbps USB-9 by the year 2030, it should simply have its own section in the USB article. This is not the same case as "LED Display" having its own page aside from "Computer Monitor." Although monitors perform basically the same function, that of transmitting images to your eyes, they do so via a whole host of different technologies. USB connectors all use basically the same technology, albeit ever-faster versions of it. Consumers of computer monitors need to know precise details of more recent versions, like OLED monitors, provided in different articles, so they can make informed decisions as to whether or not they want to purchase them. Consumers of USB technology, however, do not buy them as individual components. They simply need to know the basic capabilities of each version, contained very well in the same, comparative article, so they'll know whether to go with laptop A or pad B, and whether the technology will be backwards compatible by using an adapter cable or USB hub.Clepsydrae (talk) 21:14, 26 March 2015 (UTC)

Hello! Just checking, did you have a chance to look at the WP:LENGTH and WP:SIZESPLIT guidelines? — Dsimic (talk | contribs) 03:40, 5 April 2015 (UTC)

I've now removed the merge notice since this proposal has gone stale (2 months since last comment), and there appears to be no consensus to merge. Stickee (talk) 06:05, 9 June 2015 (UTC)

USB security

According to Wired, USB security is fundamentally broken. [5] Apparently USB sticks can carry malware even if they appear to be empty. Why isn't this mentioned in the article? I came to this page hoping to find some news on the topic (like maybe they're going to fix the problem somehow), but I found nothing. Sonicsuns (talk) 17:16, 31 July 2015 (UTC)

Ok, after some more searching I found a reference to BadUSB. But it was kindof hard to find. Maybe there should be a "security" section somewhere. Sonicsuns (talk) 17:19, 31 July 2015 (UTC)

The bad guys will find all sorts of ways of hiding malware to get it onto your system. It might have been helpful to tell us what this reference was, then we could evaluate it and come to some consensus. –LiveRail < Talk > 15:38, 9 August 2015 (UTC)

No mention of 10-pin mini connector

The 10-pin mini USB deserves mention since these are not uncommon. I believe the GO PRO camera and Blu cell phones use these. Same mini shell, but with 5 on top and 5 pins on bottom. ~ — Preceding unsigned comment added by 108.213.76.24 (talk) 18:08, 29 July 2015 (UTC)

Is it a specified connector (as in laid down on the USB specifications) or a proprietary connector? If the latter, it has no place here. –LiveRail < Talk > 15:39, 9 August 2015 (UTC)

USB 2.0 Trident logo plus sign

Please add more information about the USB trident logos. The USB 2.0 Trident logo is supposed to have an added plus sign.

www.usb.org/developers/docs/usb20_docs/icon_design.pdf

Icon design recommendation for Identifying USB 2.0 Ports on PCs, Hosts and Hubs

ww3.microtek.com.tw/tw/uploads/faq/pdf/comparison-usb2.0-cable3.pdf

The comparison between USB 1.1 cable and USB 2.0 cable

-96.233.20.34 (talk) 20:03, 24 July 2015 (UTC)

The latter reference is clearly from a WP:FANSITE. If it were a proper document issued by a reliable authority on USB, I doubt that they would have included an illustration that depicts the USB logos upside-down. As for the USB2 logo, although it is supposed to have a '+' sign as part of it, the reason some equipment makers don't bother to include it, is probably because you generally need a magnifying glass to see it. –LiveRail < Talk > 13:23, 10 August 2015 (UTC)

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Motherboard headers

Why are motherboard headers not even mentioned in the article? They should be an important part of the article. Sakkura (talk) 19:06, 27 September 2015 (UTC)

Plugs and sockets

Just noting there is a section that explains that sockets are on devices and plugs are on cables, right next to picture of an extender cable with both a plug and a socket. Maybe needs rewording. — Preceding unsigned comment added by 50.183.187.6 (talk) 18:58, 6 October 2015 (UTC)

Red Herring: Ajay Bhatt"

The following sentence is misleading:

"Ajay Bhatt, who was involved in the original USB design team, is working on a new design to make the cable insertable either side up."

It makes it sound like Mr. Bhatt is the lone owner and designer of work on USB standard and USB connectors, which is obviously not the case.

A better sentence would be: "(One of the goals of the new USB-C connector is to allow the plug to be insertable either way." — Preceding unsigned comment added by 68.115.235.85 (talk) 18:28, 17 December 2015 (UTC)

Comparisons with SCSI

There should probably be clearer comparison with SCSI. The current article mentions SCSI only once and inaccurately. It states that SCSI is not hot-swappable, but in fact many SCSI devices are hot-pluggable and hot-swappable; some can even be directly connected to USB 2 and USB 3, using the UAS protocol (supported by Linux, Windows 8, Windows 10 and Apple OS X ). — Preceding unsigned comment added by Lucchase (talk • contribs) 15:30, 19 January 2016 (UTC)

A real comparison with SCSI would probably exceed the scope of the article but SCSI or SATA may very well be hot-swappable. Thx! --Zac67 (talk) 19:09, 19 January 2016 (UTC)

Logos

https://thunderbolttechnology.net/sites/default/files/Day%201%20of%202_Thunderbolt%E2%84%A2%203%20Peripheral%20Device%20Training_Q4_15_Final_v1_0.pdf slide 11 provides a nice overview of all the logos that can accompany a usb c port. PizzaMan (♨♨) 11:01, 7 February 2016 (UTC)

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Other languages

There are almost a hundred other-language Wikipedias that have articles on USB or Universal Serial Bus that link here. So how come not a single one of the inverse links shows up in the sidebar??? --Haruo (talk) 16:33, 18 February 2016 (UTC)

For example, check the left sidebar at eo:Universala Seria Buso. --Haruo (talk) 16:34, 18 February 2016 (UTC)

Production date

The 430HX chipset included a USB host controller, starting production in May 1996.^[1] I had a computer with an Asus T2P4 in 1998 with USB that had been built in 1996. Any objections to using that as the production date? --Zac67 (talk) 14:29, 20 February 2016 (UTC)

^ http://download.intel.com/design/intarch/datashts/29055002.pdf

Charge-only cable

This feature is not properly discussed. A Blackberry phone for instance uses a charge-only cable. If a cable with no data wires is used the Blackberry rejects it. The data cable need to be present and shorted together at the Blackberry end. 78.149.211.62 (talk) 03:21, 24 April 2016 (UTC)

No mention of USB descriptors

The descriptors are essential to implementing USB. The relationship between the device descriptor, configuration descriptors, interface descriptors, endpoint descriptors, the USB#Device_classes, the actual interfaces and endpoints of the USB device, and any other device state is pretty convoluted, and should be documented here. But at the moment there's no mention of descriptors at all. Beyond Logic has done a decent job distilling the USB spec to a readable manual, and chapter 5 could be summarized to explain descriptor transmission and selection. —wing gundam 00:34, 27 May 2016 (UTC)

Illogical cable lengths

In subsection Cabling:

The USB 1.1 standard specifies that a standard cable can have a maximum length of 5 meters with devices operating at Full Speed (12 Mbit/s), and a maximum length of 3 meters with devices operating at Low Speed (1.5 Mbit/s)."

Is that really true? Why would the cable length be lower for a slower-speed connection? --Mortense (talk) 22:49, 11 January 2016 (UTC)

According to the source, it's 5 meters for USB 2.0 devices, and 3 meters for USB 1.1 devices. Basically devices with more power can use longer cables. That makes a lot more sense. Sakkura (talk) 08:47, 12 March 2016 (UTC)

I didn't bother to look this up, but my recollection is that a "Low Speed" device is allowed to have a cheaper cable. Originally, this was "safe" because all cheap cables had to be permanently attached to their devices, so if you bought an interchangeable cable, it was required to be the better, Full Speed capable cable. I think "cheaper" allowed for an unshielded cable, and maybe higher impedance as well. (Of course, nowadays, buyer beware, when buying USB "compatible" products.) 50.202.216.74 (talk) 20:56, 20 July 2016 (UTC)

USB client port

Wikipedia article Comparison of single-board computers, BrailleNote, and thousands of other pages on the Internet mention a USB client port.

I came to this article hoping it would tell me what a "USB client port" is, but I was disappointed. What is a "USB client port"? How is it different from a "USB host port", a "USB device port", or a "USB OTG port" -- or is it a synonym for one of them? --DavidCary (talk) 17:39, 12 August 2016 (UTC)

@DavidCary: The USB On-The-Go article offered a hint of an answer with "Use of USB OTG allows those devices to switch back and forth between the roles of host and client." There's no source given for that statement. Normally the terms used are "host" and "device". You can have one host on a USB bus and up to 127 devices. USB On-The-Go has a mechanism where if two On-The-Go devices are connected together that one of them will switch itself to being a "host" and then they carry on using the standard host/device protocol.

I fixed the Comparison of single-board computers, BrailleNote, and USB On-The-Go articles to not use the term "client".

This does not fix the underlying issue in that some web pages on the Internet use the word "client" though I don't know if it's common enough to merit adding to this article. A tricky aspect is finding a decent source to cite that "client" means "device" when some people talk about USB ports. The phrase "USB client" appears four times on www.usb.org.^[6] I looked at how the word "client" was used on all four hits and it was always in the context of "client driver" software but I did not see an explanation of what that is. The phrase "client port" is never used on www.usb.org.^[7] Thus while "USB client port" appears about 8,750 times on the Internet^[8] it seems to be a non-standard term. --Marc Kupper|talk 00:09, 19 August 2016 (UTC)

USB type C

Type C is hardly described only mentioned. Pinning is missing, current max cable and other properties are not mentioned. 193.25.102.252 (talk) 12:32, 25 September 2016 (UTC)

Split in USB 2 and USB 3 USB type C

The characteristics, cabling, connectors of USB 2, 3 and type C are sufficiently different to have a different page for each of them. The way USB is described now is rather convoluted. Theking2 12:38, 25 September 2016 (UTC) — Preceding unsigned comment added by Theking2 (talk • contribs)

"Firstly conceived for..."

§ USB mass storage / USB drive says

Firstly conceived and still used today for optical storage devices (CD-RW drives, DVD drives, etc.), several manufacturers offer external portable USB hard disk drives, or empty enclosures for disk drives.

What was "Firstly conceived for..."? Not the manufacturers. Not the "external portable USB hard disk drives, or empty enclosures for disk drive". Apparently not the wide range of "computer peripherals (including keyboards, pointing devices, digital cameras, printers, portable media players, disk drives and network adapters) to personal computers" referred to in the first sentence of the second paragraph of the article. What, then? -- Thnidu (talk) 18:02, 11 November 2016 (UTC)

I guess this is supposed to refer all the way back to the USB mass storage class. --Zac67 (talk) 18:26, 11 November 2016 (UTC)

@Zac67: That's my guess, but I'm not certain. While you were adding that note I was posting a version of this to Wikipedia talk:WikiProject Computing § Description of (something's) origin in USB needs clarification; see there for more discussion. --Thnidu (talk) 18:41, 11 November 2016 (UTC)

There needs to be a table with images of all the USB types, what they're called, and a short (1-2 sentences) blurb about them.

A lot of people come to this article looking for a simple list of usb connector types (I know I did), but this page doesn't actually have one. There is a table showing what usb connectors fit together, but it's a fair way down the page and somewhat hard to find. When you google "List of usb cable types", google comes up with this page, but can't identify a list properly, and displays some unrelated table. This means that anyone who wants to identify some cable they found in their garage, or needs a simple text list of all usb cable types, has to actually visit the article and look around. I feel that adding in a list of all usb types near the top could fix this easily and save a lot of people's time. twotwos (talk) 22:06, 10 January 2017 (UTC)

Unclear sentence

The first clause of this sentence under Durability doesn't make sense (accomplish what?). Could someone with more expertise make it clearer?

Features intended to accomplish include, a locking device was added and the leaf-spring was moved from the jack to the plug, so that the most-stressed part is on the cable side of the connection. — Preceding unsigned comment added by Jwarhol (talk • contribs) 02:02, 21 January 2017 (UTC)

Questionable Link for reference 62

Reference 62 linked directly to an IP address instead of a domain name, making it difficult for reader to decide if they want (or should) follow the link. Also, at the time of this writing, the link does not work: 193.219.66.80/datasheets/usb_20/Micro-USB_final/Micro-USB_1_01.pdf

Reference 62 is: "Universal Serial Bus Micro-USB Cables and Connectors Specification to the USB 2.0 Specification, Revision 1.01" (PDF). USB Implementers Forum. 2007-04-07. Archived from the original (Zip) on 2007-04-08. Retrieved 2010-11-18. "Section 1.3: Additional requirements for a more rugged connector that is durable past 10,000 cycles and still meets the USB 2.0 specification for mechanical and electrical performance was also a consideration. The Mini-USB could not be modified and remain backward compatible to the existing connector as defined in the USB OTG specification." — Preceding unsigned comment added by 96.20.68.251 (talk) 00:31, 22 January 2017 (UTC)

This article is in desperate need of revision

This article is in desperate need of revision and update. The major problem with it is that it - or at least major parts of it - was obviously written before USB 3.1 was issued. The article is factually wrong - for instance a picture of a USB type-A pin-out is actually of a USB 1.0 type-A pin-out. This is enormously confusing or can be. The article needs a rewrite from the modern perspective. It should include the enormous criticism of the earlier versions of the standard - including Intel's famous "superposition" poster. The potential CONFUSION between the old connectors and the new super-speed connectors (type-A, type-B and micro type-C) should be PROMINENT, not buried in the details. The tables need to be placed in a context which makes them intelligible. The table "USB connectors mating matrix (images not to scale)" is really bad. I do think the diagrams of the plugs and receptacles included are quite useful, but the table itself is not only silly, but confusing. For instance look at the entry for a type-A plug and a type-A superspeed receptacle. It is in green - which means what? I have no idea what green means, especially for those who are red/green colorblind... But the entry is "only non-superspeed" - what is that supposed to mean?!? There are two categories of mating, I think: physical and electrical. There are also considerations about damage and orientation (that is, is damage possible? is incorrect orientation possible?) The fact that a "USB 3.0 type-A" receptacle might not have 9 pins but still be covered under the 3.0 standard makes the entire exercise in precision difficult if not impossible. How you reconcile a table with this kind of vague specification (obviously, the standard was written be a committee with competing commercial interests) is difficult if not impossible. Anyway, the table basically has mostly wasted space and should be removed. The diagonal is the only entries with "Yes" and what is meant for the type-A, type-B and type-micro B "only non-SuperSpeed" is anyone's guess. You don't need a table to convey that information, and since whatever "only non-SuperSpeed" means is NOT conveyed in the table, it shouldn't be there either. The next table "USB cables matrix" is worse. First, it doesn't even have 3.0 cables except for SuperSpeed micro-B and type-C. Second it implies there is a practical difference between "Yes" and "non-standard". Anyone coming to that table probably has a specific configuration in mind, whether that config is available has nothing to do whether or not it is "standard". That is, the table is practically useless. I question its original value, and since the USB standard configs have turned out to be so often IGNORED, I think it's obvious that the table isn't useful. Finally, the pin-outs is OBSOLETE!! As of today, the CURRENT USB standard is 3.1 (with 4.0 being discussed). The information doesn't show ANY 3.1 gen 1 or 3.1 gen 2, pinouts! Worse, the reference to the 3.0 pinouts is the same - IT IS OBSOLETE not even referencing the 2013 USB 3.1 STANDARD!! But it doesn't! Wow, I mean its been nearly 4 years fellas.174.131.58.70 (talk) 17:29, 26 January 2017 (UTC)

Typo in image: USB Micro-B USB 2.0 vs USB Micro-B SuperSpeed (USB 3.0)

The image, USB Micro-B USB 2.0 vs USB Micro-B SuperSpeed (USB 3.0) (link), contains a typo. The text at the top of the image erroneously states that the image describes a “Macro” type. Presumably, the image author meant to write “Micro.” Wikem (talk) 03:28, 20 February 2017 (UTC)

Two different images showing the same

The article has two images showing basically the same thing:

http://en.wiki.x.io/wiki/File:USB_3,_Mike,_Headphone,_USB_2_jacks.jpg

http://en.wiki.x.io/wiki/File:USB_2_and_3.jpg

Isn't there some sort of redundancy rule against that? Seems unnecessary to include both. — Preceding unsigned comment added by 195.249.185.186 (talk) 10:16, 4 March 2017 (UTC)

buried in details

i concour with the above comments by twotwos (talk) 22:06, 10 January 2017 (UTC) and 174.131.58.70 (talk) 17:29, 26 January 2017 (UTC). confusing and buried in details the article felt during reading. a clear overview (perhaps in table format) would contain: usb socket/plug name - starting year - which socket/plug it fits (with a warning if such pairing is only physically possible but not functional!) - data speeds available - power output available through this connection - miscellaneous information.

an image of 6 different usb endings with no apparent time order and a list of their names in the picture text is just sub-optimal. it would be better to post images by one type (pair of plug and socket) at a time and put them under the relevant sub paragraph dealing with their description. 176.63.176.112 (talk) 13:19, 5 March 2017 (UTC).

USB chargers 2

There's a lot of information either not in Wikipedia or at least not accessible to the layperson who is likely to be looking for it.

My Samsung Galaxy Mini for example will not generally charge at all from a 2.4A dumb port, or from 240V chargers that come with other brands of 'phone. It will charge from a computer USB port, or from a 1A dumb port. Many other devices are also a bit finnicky I am told. A friend left her charger at my home, 4 hours drive from mine. I told her to charge her 'phone from her computer (she had a suitable lead, used with her car charger) but it was terribly slow. I'm unsure of her 'phone details, I will find out.

Recently there have come on to the Australian market chargers (both 12V DC for use in cars and 240V AC for use at home etc) which have multiple charging ports of different types. I have an in-car device from Aldi which has both 2.4A and 1A USB ports, and only the 1A port charges my 'phone. I have a 240V "Click" charger ("Click" is a Bunnings house brand) with 1A, 2.4A and smart "I/O" ports and again my 'phone will charge from any except the 2.4A port. The packaging of this "Click" charger claims it will charge anything, and it has not failed yet, but it's a matter of knowing which port to use. There are also chargers built in to GPOs, again of several sorts. I'm about to install one that comes with "high and low power" USB ports, and instructions that if one of the two ports doesn't work with a particular device, just try the other. [9]

This OR doesn't belong in the article of course. But this and similar information would be appreciated by our readers I'm sure once properly sourced. http://www.iec.ch/newslog/2011/nr0311.htm is a good place to start. Andrewa (talk) 08:41, 24 March 2017 (UTC)

USB chargers

I think we need an article at USB charger or similar, giving a simple overview of the USB chargers available and what they're good for.

I have a Samsung Galaxy mini smartphone and it will charge from intelligent ports and dumb 1A ports but not from dumb 2.4A ports. Took me ages to work out what was going wrong. Many of the chargers available in Aus offer only dumb 2.4A ports. NBG. Andrewa (talk) 12:02, 27 January 2017 (UTC)

See #USB chargers 2 below. Andrewa (talk) 08:42, 24 March 2017 (UTC)

Non-standard cables?

I think this section, and the associated picture, should go. The article is complex enough without pulling in the 101 hacks and non-standard stuff people may have come up with. I don't see evidence that this or any others have acheived any sort of cross-over to 'defacto standard' level. Any strong objections? Snori (talk) 07:13, 24 April 2017 (UTC)

USB_konektory.png incorrectly shows the USB micro-B connector

In the http://en.wiki.x.io/wiki/USB#/media/File:USB_konektory.png

the micro-B connector is incorrectly drawn. the connections are displayed on the opposite side of the plug and upside down.

NO micro-B cable will fit the diagram in USB_konektory.png that displays the micro-B incorrect layout.

You can verify this on the photo of a real micro-B usb connector at this URL:

https://encrypted-tbn1.gstatic.com/images?q=tbn:ANd9GcSUO3I53I7X1Q_rkOI8MY5iQ5zVqwgZVpN1HygpEdp0308pKEXk — Preceding unsigned comment added by 49.182.94.229 (talk) 01:37, 8 March 2017 (UTC)

That's true. Moreover, USB 3 micro-B is also "flipped" in that image.

I also think that all micro connectors in the image should also be drawn rotated 180º, to be consistent with "USB connectors mating matrix" in article. --Circulosmeos (talk) 16:13, 24 August 2017 (UTC)

The 'top' of a micro-B connector is the rounded side – compare to standard-B. --16:29, 24 August 2017 (UTC)

ok, so images for "micro" connectors should be rotated for consistency. But note that rotating micro-B images, leaves the "hole" in an incorrect position. --Circulosmeos (talk) 17:48, 24 August 2017 (UTC)

High Speed Serial Interface with differential I/O - and protocols

Cool. It's got 5v, Ground, + and - signals ... Hmmm. So it's like every other serial interface every invented, with all the "extra" conductors removed and some topological constraints laid on top. I think everyone could get that if someone would just say it plainly. The "operational modes" are built on top of the hardware layer, so it's a dual-specification, since it describes both the hardware and the software protocol(s). There ya go. Simple. Hint: It doesn't have a separate "clock" signal, so you know it's asynchronous or isochronous. USB devices do, however, have UARTS. So it's essentially a grown up RS-422. 98.194.39.86 (talk) 05:09, 26 September 2017 (UTC)

Upstream/downstream?

It would be useful to be explicit about what upstream/downstream port/device mean. The information is in the article, but it takes some parsing to make sense of it, because at first it's confusing, and looks inconsistent. I suggest something like the following text, either in the Overview, or in ‘Standard Connectors’, or in ‘Power’:

Power flows from ‘upstream’ devices to ‘downstream’ devices. An ‘upstream port’ is (possibly confusingly) on the downstream device (‘facing up stream’, as it were), and vice versa. The A plugs are intended to go into upstream devices and the B into downstream, so that power flows from A to B, though this principle is not applied completely consistently. NormanGray (talk) 10:09, 8 August 2017 (UTC)

They don't say, because they don't know. Look elsewhere for the actual spec. It can transmit bi-directionally, but it's really designed for most of the data to flow in one direction. When they say "downstream", they mean non-hub / controllers. But it's a bit more complex than that, and so they left you hanging. Just remember, in a daisy-chain or star serial topology, only one "device" can control the bus (talk) at one time. (Otherwise, the data would get stommped on.) 98.194.39.86 (talk) 05:15, 26 September 2017 (UTC)

Cable type grid and USB On The Go

It seems the cable type grid is missing the ones in the USB OTG (On The Go) Standard. These should be marked specifically, because they have special wiring to signal that the port in question should be switch to Host Mode. Should these be added, or should they only be on the USB OTG page?--Robert Wm "Ruedii" (talk) 13:21, 20 November 2017 (UTC)

As a note, I would add it right now and gracefully let it be undone if the ruling is the other way, but I don't have the time, and I don't know if I'll remember to get back to it, so if someone wants to do it for me, I'll be very grateful. Just remember to give special marking of it being "USB OTG" standard. --Robert Wm "Ruedii" (talk) 13:57, 20 November 2017 (UTC)

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New Section: Overview: Receptacles (Sockets) Identification

I have added a new section. The purpose of the section is two-fold.

First, because I think the most frequent usecase for looking at the page will be for a user to figure out which kind of connector they need to plug into some computer or gadget. Indeed, some diagrams for the USB receptable are missing from Wiki Commons, so I had to link to an external source. They were not well served by the complex tables at the end.

Second, because it would better allow the kind of split that is mooted above, such as moving technical details into separate pages without frustrating users by making them click more for simple lookup.

I considered putting in figures of both plug and socket. Someone else can feel free to consider doing this if it useful. People may start looking at their cable plug, but they actually have to start with the equipment socket! "Receptacle" is the standard USB terminology for a socket.

Another approach to consider would be to fold this new section into the sidebar, which is not up-to-date and not particularly useful, IMHO. Rick Jelliffe (talk) 04:24, 24 April 2018 (UTC)

Split out Connectors, Cabling and Power

Text and/or other creative content from this version of USB was copied or moved into USB_(Physical) with [837995105 this edit]. The former page's history now serves to provide attribution for that content in the latter page, and it must not be deleted as long as the latter page exists.

The previous article was 191 kB and difficult to navigate.Rick Jelliffe (talk) 09:13, 24 April 2018 (UTC)

Split out Signaling, Protocols and Transaction

Text and/or other creative content from this version of USB was copied or moved into USB_(Communications) with [837997932 this edit]. The former page's history now serves to provide attribution for that content in the latter page, and it must not be deleted as long as the latter page exists.

The previous article was 191 kB and difficult to navigate.Rick Jelliffe (talk) 09:13, 24 April 2018 (UTC)

Factoring March 2018

Is this article overly long? Could it be factored into a main and sub-articles, perhaps puttingall the protcol details into a sub-article? --Wtshymanski (talk) 16:51, 21 March 2018 (UTC)

According to Wikipedia:Splitting, and article over 100kB readable text almost certainly should be divided. The article is currently about 131kB. More importantly, there is an obvious split: we already have an article on USB 3.0 and much of this article is about USB 2.0. So moving out the USB 2.0 material would be useful. However, the material is pretty much interleaved, so a topical split would be more practical.    Rick Jelliffe (talk) 07:32, 24 April 2018 (UTC)

Split done.Rick Jelliffe (talk) 09:21, 24 April 2018 (UTC)

the mention of 20v in the table...

is wrong..--a google search of 'usb 20v' shows proper perspective, that of a dewalt battery with a usb port [buck converter inside]. 68.178.25.95 (talk) 01:38, 17 September 2018 (UTC)

USB 1.0 vs USB 1.1

The Wikipedia article says that USB 1.0 supports both 1.5Mbps and 12 Mbps, but this Sony article says USB 1.0 only supports 1.5Mbps, and that the USB 1.1 supports 12Mbps: https://www.sony.com/electronics/support/articles/00024571

Is the Wikipedia article wrong?

--MisterSanderson (talk) 17:22, 14 February 2019 (UTC)

No, Sony is wrong. The differences in USB 1.0 vs 1.1 concerns hubs; the 1.0 spec had some problems that were fixed in 1.1. If you can get hold of the 1.0 specs – sadly not free - you can see that it already has Low and Full Speed. --Zac67 (talk) 18:09, 14 February 2019 (UTC)

USB4 not USB 4

According to sources, the draft of the new standard is right now USB4, without the space. Probably such an article should be created, even for now could be just a redirection. jynus (talk) 14:25, 5 March 2019 (UTC)

Ars Technica reported ^[1] that Intel gave Thunderbolt 3 specs to USB-IF to be the basis of USB4. The USB Promoter Group announced this pending USB4 spec on March 4, 2019 ^[2]. — Preceding unsigned comment added by Ebjay1 (talk • contribs) 20:18, 9 March 2019 (UTC)

stale lead sentence: USB is ... between personal computers and their peripheral devices

Should ... "between personal computers and their peripheral devices" be changed to something more generic like between computers? Examples: TVs have USB ports, phones, tablets, etc... Daniel.Cardenas (talk) 18:07, 29 April 2019 (UTC)

Went ahead and changed it to: "... between computers, peripheral devices and other computers." Daniel.Cardenas (talk) 18:15, 29 April 2019 (UTC)

USB 5.5V VBUS

There is an ECN called "USB 2.0 VBUS Max Limit" that increases VBUS operating range to 5.5V. I'm not sure when this applies, but it is modifying the USB 2.0 spec rather than only applying to new revisions. It might be necessary to note this on the voltage range sidebar. https://usb.org/sites/default/files/usb_20_20181221.zip, USB 2.0 ECN VBUS Max Limit.pdf -- 47.151.2.100 (talk) 22:00, 1 May 2019 (UTC)

History with iMac

This page claims that iMac was the first computer (or "mainstream product") with USB support, but the cited source does not make this claim. It makes the claim that iMac helped USB get more widespread support.

The iMac’s sole reliance on the USB interface meant that Mac users had to throw out all their old mice, keyboards, scanners, printers, and external drives. The computer’s lack of SCSI ports particularly scared Mac pundits, who long relied on SCSI for external storage. But at the same time, the iMac provided the first kick start USB needed to really get off the ground. Thanks to the iMac, many peripheral manufacturers launched their first-ever round of USB computer accessories—it was no coincidence that most of them shipped in transparent blue-green housing.

^[3]

Another source makes the claim that other computers had USB ports at the time, but iMac was the only one that dropped support for other connectors.

The original iMac was the first computer to ship exclusively with USB ports, as it did away with famed legacy ports like ADB and SCSI. At the time, computers that happened to ship with USB ports also came with other peripheral connections like serial and parallel ports.

^[4]

References

GeirGrusom (talk) 13:55, 25 June 2019 (UTC)

There have been no renaming!

Within USB there have not been any renaming. People who think there have been need to reed up on semantic versioning. USB 3.0 is NOT the same as USB 3.1 Gen 1 as USB 3.1 supports different kinds of connectors than USB 3.0. — Preceding unsigned comment added by 85.144.6.21 (talk) 15:11, 4 September 2019 (UTC)

Serial or Parallel?

The infobox lists USB "Universal Serial Bus" as a serial connection. However when I look at the pinout for USB 3.0 I can count no less than 3 data "differential pairs". This "serial bus" has 6 wires to transmit data! Doesn't that make it a parallel bus? — Preceding unsigned comment added by 146.151.105.188 (talk) 18:01, 31 October 2019 (UTC)

First, each pair is used for Differential signaling, so each pair is two wires sending one bit. One pair is for backward compatibility with 2.0. The other two pairs send in different directions, to enable full duplex communication. A parallel bus would allow all the wires to be used for any purpose - that isn't the case for USB, where everything has a predefined role. - MrOllie (talk) 18:14, 31 October 2019 (UTC)

It's serial. The pinout for A/B can show up to three differential pairs: one in half-duplex for low/full/high speed (USB 1.x/2.0) and two in dual-simplex for SuperSpeed (USB 3.x). USB-C adds a second half-duplex low/full/high speed link and two in dual-simplex for the additional lane for SuperSpeed 20G. It's not a bus though, at least not electrically, just logically. --Zac67 (talk) 18:20, 31 October 2019 (UTC)

USB-A, USB-B

USB-A and USB-B redirect here, but are not mentioned in the article. A and B need to be explained here, or need their own articles, which would probably be unnecessary (USB-C has its own article.) Numbersinstitute (talk) 21:14, 4 June 2020 (UTC)

See http://en.wiki.x.io/wiki/USB#Receptacle_(socket)_identification Notrium (talk) 02:29, 10 June 2020 (UTC)

deprecated?

the table implies that the only slot and plug left since 2017 is USB-C. This makes no sense as USB-C cables come with type A on the other end.Gendalv (talk) 21:50, 9 August 2019 (UTC)

First, deprecated does not mean removed, second, as you can see with latest galaxy tab S6, galaxy note 10, etc., all functions (in particular USB Power delivery 3.0 with PPS) are only available with USB-C to USB-C with e marker cables. Also Thunderbolt 3 (and thus USB4 main alternate mode) will only (obviously) work with USB-C to USB-C COMPATIBLE with thunderbolt 3 (and PCI express) cables. ZBalling (talk) 20:51, 3 September 2019 (UTC)

Alternate mode is in the USB-C spec but not in the USB4 spec. USB4 is based on Thunderbolt 3 (but is not the same) and includes backward compatibility with Thunderbolt 3 as well as USB 3.2 and 2.0. USB-C is just a spec for cable and connection which allows the other end to have whatever other connector is available. The table here simply states that USB-C is the only cable/connector that is used for the given USB version thus both ends need to be USB-C. Whenever you connect a USB-C with USB-A on the other end it will simply use a different (read: older) USB version (in most cases that would be USB 2.0 or 3.0 since these are the most used ones). The reason for that is that the USB protocol has backwards compatibility with some of its older versions. 85.144.6.21 (talk) 15:22, 4 September 2019 (UTC)

Remember that USB-C is not only a USB4 plug -Muonium777

Muonium777 (talk) 18:14, 25 January 2021 (UTC)

[1] ttp://www.ti.com/lit/pdf/sllu214

[2] ttp://download.intel.com/design/intarch/datashts/29055002.pdf

[3] ttps://arstechnica.com/gadgets/2019/03/thunderbolt-3-becomes-usb4-as-intels-interconnect-goes-royalty-free/

[4] ttps://usb.org/sites/default/files/2019-02/USB_PG_USB4_DevUpdate_Announcement_FINAL_20190226.pdf

[5] ttps://www.macworld.com/article/1135017/imacanniversary.html

[6] ttps://www.networkworld.com/article/2230092/five-technologies-in-the-mainstream--thanks-to-apple.html

[1]

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[2]

[3]

[4]