And don't go plugging in strange USB devices.
Joy's iPhone wasn't charging. To narrow down the problem, I plugged it into the self-powered, many-port USB hub that's stuck to the side of my desk.
The eval boards that I currently have plugged into that hub promptly lost power. Oopsie! Must be the tattered Apple-specific cable has shorted out (and of course there's no spare handy; the only other Apple USB cable around here is for an old iPod Touch, and that's the old-model proprietary Apple cable).
Aside from which, my workstation (into which the upstream port of said hub is plugged) was unceremoniously turned off. Eh?
Just a reminder that a disconcerting number of PC motherboards (and this wasn't a bargain-basement model) don't have proper protection on the USB ports. I'd had trouble with an earlier motherboard when a self-powered hub fed voltage back on the upstream port and it ended up feeding into the motherboard's 5V rail when the PC was turned off; this one apparently doesn't have any sort of current limiting, so a downstream short can shut down the system.
(I think this particular port may be powered from the 5V Standby rail, to allow for keyboard wake-up buttons and suchlike. That supply doesn't have a lot of current available, and is also the supply that's used to turn the main supply on, so shorting it out will cause the main power to turn off.)
Anyway... pressing the power button and waiting restored normal operation, and I had in fact saved my work, so no real harm done.
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