Re: Is a USB cable for data, or only power; how to tell without testing it?
nospam <[email protected]>
| Newsgroups | alt.comp.os.windows-10,alt.comp.hardware,comp.mobile.android |
|---|---|
| Organization | A noiseless patient Spider |
| Message-ID | <021220212135039201%[email protected]> |
In article <[email protected]>, micky <[email protected]> wrote: > Short of testing a cable, is there a way to tell by looking if a USB > cable is data/power or power only? > > Is there a logo or a mark on the plug or wire? anything with an official usb logo has power and data, since that's required by the spec. there is no such thing as a usb power-only cable because it's in violation of the spec. the amount of current must be negotiated over the data lines, so a 'power-only' cable' that has no data lines will be unable to negotiate and end up at the default 100ma. counterfeit cables might use the logo without authorization, so a logo is not a guarantee. > If not, why not? Do they want to drive us crazy? because some companies want to sell crap. some devices are non-compliant and might work with non-compliant cables, so they sorta work. sometimes. > Sort of separately, I found a cable on the street, white, good condition > everywhere, USB-A to USB-C, well-made, and on the USB-A end is written > PISIGMA. usb-c cables vary, making it difficult to impossible to tell by looking at it what its specs are.