Re: USB devices fail unnecessarily on unpowered hubs

From: Randy.Dunlap
Date: Thu Jun 01 2006 - 19:42:41 EST


On Thu, 01 Jun 2006 17:35:22 -0600 Robert Hancock wrote:

> linux-os (Dick Johnson) wrote:
> > Many, most, perhaps all such devices don't take more power when they
> > are "enabled". Everything is already running and sucking up maximum
> > current when you plug it in! If the motherboard didn't smoke when
> > the device was plugged in, you might just as well let the user use
> > it! Perhaps a ** WARNING ** message somewhere, but by golly, they
> > got it running or else you wouldn't be able to read its parameters.
>
> Wrong.. USB devices are not allowed to draw more than some amount (100
> mA I think) of power before the host tells it that it is allowed to
> switch into full-power mode. Any device that doesn't do this doesn't
> comply with the USB specs. Therefore it is very possible to connect a
> device and discover that it can't be enabled.

so does Thunderbird on Windows have absolutely no Reply-to-All
and no References or In-Reply-To capabilities?

---
~Randy
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