Switching on/off 5V power to a USB port

[Poul-Henning Kamp]

In message <4F7B761B.4030104 at fuzzwad.org>, Ron McDowell writes:

>I just got a little USB powered fan and it sure would be nice if I could 
>have cron on my FreeBSD box turn it on or off at certain times by 
>switching off the 5V line on a USB port.  Anyone know how I can do 
>that?  Thanks.

I have only found very few USB ports where it was possible to reliably
control power with a published interface.  Most USB-controllers support
doing it, but most motherboards don't mount the necessary FET.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk at FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.