Re: USB functionality.

On 2024-03-09 23:09, Roger Hayter wrote:

On 9 Mar 2024 at 21:54:51 GMT, "Andrew Smallshaw" <andrews@sdf.org> wrote:
 

On 2024-03-09, peter@easthope.ca <peter@easthope.ca> wrote:

>
This photo,
https://commons.wikimedia.org/wiki/File:USB-OTG_Setup_IMG_2342.JPG
suggests, to me at least, that the phone can be charged while the
keyboard, mouse and flash store are used.  True?

>
There are altogether too many unknowns here.  Looking at the date
of the photo - 2015 - some phones of that era could support USB
OTG but were unable to supply power to connected peripherals,
meaning you would need a Y cable to supply that separately.  Others
could do the job inclusive of power delivery, others couldn't work
in OTG mode at all.  Generally you couldn't use OTG and charge
simultaneously, it's a role reversal that early USB wasn't designed
for.
>
Things are different with USB-C but of course that is much later.

 But can even USB-C accept a signal input (keyboard and mouse for instance) and
unrelated signal output (audio for instance) on the same physical socket? I
ask only out of curiosity.

Certainly.
That's normal USB functionality. It is a bus. You need a hub, though, in order to split the cables, one for each device.
The only problem is which device supplies the power and in what direction.
--
Cheers, Carlos.