Talk:USB hardware

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Connectors

The first paragraph launches into discussion of sizes (standard, mini, micro) and speeds (Low Speed, Full Speed, High Speed, SuperSpeed & SuperSpeed+). Following that is the paragrgraph explaining topology (Unlike other data buses ...) with the upstream/downstream distinction. Logically the order of the two paragraphs should be reversed; topology should be explained before connector size and speed.

The explanation of upstream/downstream orientation is there and the explanation of A/B is there but the relationship between orientation and A/B is left implicit. For any reader who doesn't already understand the subject, explicit would be better than implicit.

Comments? Any objection to improvements? Thanks, ... PeterEasthope (talk) 14:38, 10 November 2019 (UTC)[reply]

@PeterEasthope: Sorry this hasn't gotten any response in three years. You certainly make valid points and have my support. Can you tell whether these issues still need to be addressed? — voidxor 23:19, 23 May 2023 (UTC)[reply]
Just swapped the two paragraphs as suggested earlier. Let's see whether the change is tolerated before investing effort to explain the relationship of orientation to A/B. Thanks for the interest. ... PeterEasthope (talk) 13:58, 25 May 2023 (UTC)[reply]
Very good, thanks! You can wait if you like, but I get the sense from the history that there's not a lot of editors here. I would suggest appending, at minimum, something like "per talk" to your edit summaries so that anybody viewing your edits can find this discussion with your detailed reasoning. — voidxor 16:51, 25 May 2023 (UTC)[reply]

USB UC-E6

I couldn't find anything about USB UC-E6 in the article. Are there other USB UC connectors? UC=Ultra Compact? --2A02:810A:1E40:A14:1826:696D:92DD:D906 (talk) 10:10, 25 October 2022 (UTC)[reply]

This looks like another nonstandard connector to me. See any of the other discussions on this talk page. — voidxor 00:20, 24 May 2023 (UTC)[reply]

Cable differences between USB 1.x and 2.0?

The Cabling section is a little terse. Can anybody tell me if the cable standards (e.g. wires, twists, shielding) changed at all from USB 1.x to USB 2.0, other than the slight change of the maximum allowed length? I realize that was 23 years ago. Even if there was no real change (in other words, a pre-2000 USB version 1 cable would be within spec for 480 Mbit/s USB version 2 connections), I think that would be worth mentioning. — voidxor 18:00, 25 May 2023 (UTC)[reply]

Citation for "USB does not allow extensions cables"

Throughout the article there are several statements to the tune of "USB does not allow extensions cables" (specifically at https://en.wikipedia.org/wiki/USB_hardware#Connectors under the image for a non-standard extension cable and the first image in the article). However, this statement is not cited or referenced at all. Without personally going through the USB specification to see if this is true or false, the only talk about this seems to be from @Voidxor above referring to this archived discussion on the topic

It may prove beneficial to find an official source for this statement to reference, or failing that, append the good old [ citation needed ] to each mention of extension cables not being allowed. 61.69.232.98 (talk) 12:46, 1 July 2024 (UTC)[reply]

This took less time than I'd feared. In revision 2.0 of the USB standard dated April 27,2000 (available on the USB.org Web site), section 6.4.4 "Prohibited Cable Assemblies" says explicitly that extension cables are not allowed because they can create a cable that exceeds the allowed length. --Wtshymanski (talk) 17:10, 1 July 2024 (UTC)[reply]
 Done. Thanks for the legwork, Wtshymanski. — voidxor 23:04, 1 July 2024 (UTC)[reply]

A-A cables are actually permitted by the standard (SuperSpeed only, no power)

The article claims about A-to-A cables: "Existing for specific proprietary purposes, not inter-operable with USB-IF compliant equipment and possibly damaging to both devices when plugged in. [...] Other combinations of connectors are not compliant. There do exist A-to-A assemblies, referred to as cables (such as the Easy Transfer Cable); however, these have a pair of USB devices in the middle, making them more than just cables."

But the USB 3.0 standard describes a "USB 3.0 Standard-A to USB 3.0 Standard-A Cable Assembly", which works for SuperSpeed only and does not have the USB2 pins except GND (VBUS, D-, D+) connected through. (Those cables are mainly used for stuff like debugging of the operating system.)

(And those cables actually exist - for example, https://www.datapro.net/products/usb-3-0-super-speed-a-a-debugging-cable.html sells them. I've used one myself.) TheJH (talk) 00:14, 4 August 2024 (UTC)[reply]