Tim: > > I've never come across a charge-only cable. I understand why someone > > would use one (e.g. public charging), but I thought some use of the > > data pins was necessary to switch from lower power mode. > > > > If you keep unusual cables, label them. It'll save you from some > > headaches in the future. Frederic Muller: > Yeah... funny you wrote this as I was wondering they make those kind of > cables as the extra cost for full data cable is really not much and > secondly why they are not labelled as such! ... guess I could indeed > label them myself. > > I usually get those when buying cheap battery-powered stuff requiring a > cable to charge its battery. So I will label them when I identify some. After many years of accumulating equipment with external power supplies, I've come to labelling what they belonged with. Quite often the specs written on the device are too vague, and find one plugpack could power several devices, but only one plugpack will power a specific device. USB cabling is a bit like that. If you get a gadget that uses a USB connection simply as a 5 volt supply, they may just wire up the two supply pins to the cable, and hope that any USB port will supply as much current as the device needs (according to spec, dumb wiring should only supply a very minimum of current, which won't be enough for most things, and higher amounts need negotiating). They may put some extra bits in the supply end of the plug that tells a slightly smart power supply to supply more current, or it could be in the device (necessitating a fully wired USB lead). But for the really smart (I hate that description) devices and supplies that have more voltage and current options, there's supposed to be more to it than just jumpering some pins together in one plug in the cable. As an example, a friend had to faff about finding the right cable to recharge his tablet. Some cables don't work. It could be that the wiring is so thin that there's significant loss across the cable. Or, it's more likely that it needs more than a plain two-wire cable to work, and perhaps a specific charger, too. People tend to think of USB as being universal (it is named that way), but it's far from it. There's a bunch of variations, and the lowest common denominator is very low. -- uname -rsvp Linux 3.10.0-1160.119.1.el7.x86_64 #1 SMP Tue Jun 4 14:43:51 UTC 2024 x86_64 Boilerplate: All unexpected mail to my mailbox is automatically deleted. I will only get to see the messages that are posted to the mailing list. -- _______________________________________________ users mailing list -- users@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to users-leave@xxxxxxxxxxxxxxxxxxxxxxx Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/users@xxxxxxxxxxxxxxxxxxxxxxx Do not reply to spam, report it: https://pagure.io/fedora-infrastructure/new_issue
