[clug] A "mount" defeat - was Re: Persuading Debian to talk to an Android tablet via USB?

Hal Ashburner hal at ashburner.info
Thu Oct 21 05:53:40 MDT 2010


  On 21/Oct/10 10:37 PM, Alex Satrapa wrote:
> The theory is that a USB port controller is supposed to be able to 
> negotiate with devices about whether to provide power, and if so, how 
> much. The USB port is supposed to be able to supply up to 1.5A, and 
> some high-power devices will request the "whole nine yards"
Or more, eg the dual usb cable plugs that power 2.5" usb hard drives, 3G 
modems and such. My understanding is modern usb ports actually supply 
more than spec when requested meaning you only have to plug into one 
port. My current laptop has no issue with one port, my older IBM T42 
required two ports for the same drive.

Anyway an SD reader shouldn't require loads of power, just about any usb 
port /should/ do. But I haven't got a better guess as to why felix's 
isn't working beyond maybe it's just a flaky PoS. Who knows?


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