 Usb Power Budget, Is powering usb peripherals unsafe? |
 Nov 18 2006, 08:09 AM
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 Group: Members Posts: 106 Joined: 19-October 05 From: Cardston, AB, Canada Member No.: 8,348  |
I'm running OZ on my C1000, but I think this is a fairly general question.
In kernel 2.16 and newer, if a USB device requires too much power, it is not enabled. 'dmesg' output might look like: QUOTE usb 1-2: no configuration chosen from 1 choice To find out how much power a USB device wants, one can invoke: QUOTE lsusb -v | grep MaxPower My card reader wants up to 250 mA, and my USB to serial converter says it might use up to 500 mA! Post #3 on this ubuntu forum thread describes a work-around. So my question is, is it safe to do this? [Also, I assume that people who are using kernels before 2.16 could well ask the same question, even if the device isn't automatically disabled.] Are the manufacturers of these USB products giving a high margin of error? Can a high-current device damage a Zaurus, or will it simply shorten battery life or just plain not work? Thank you, Armagon [Edit]. PS. Does it make any difference if the Z is plugged in or not? |
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Posts in this topic
Da_Blitz there was a recent bug fix that turns off devices ... Nov 18 2006, 07:36 PM
speculatrix the guy who put usb wifi and bluetooth inside a C1... Nov 20 2006, 03:56 PM  |
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