Talk:USB

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High traffic

On 28 May 2015, USB was linked from Slashdot, a high-traffic website. (See visitor traffic)

USB chargers[edit]

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)

USB_konektory.png incorrectly shows the USB micro-B connector[edit]

In the https://en.wikipedia.org/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)

Non-standard cables?[edit]

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)

Upstream/downstream?[edit]

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)

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

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)