On 10/25/07, William Chops Westfield wrote: > > On Oct 24, 2007, at 7:47 PM, Matt Pobursky wrote: > > > I've never seen a USB host or hub that dropped power to an external > > device whether it was bus powered or self-powered. > > My mac will drop power to devices connected via the hub in the keyboard, > if it detects that they're drawing too much power (and I get a nice > popup to the effect that I have a USB device drawing too much power, > too.) I read quite some website about USB things and often Mac is touted to abide by the USB standard much better than Windows and even Linux. However it seems Mac is similar to other OS when it comes to USB powered harddisk. They are supposed to be illegal USB device but all the major OS seem to support them. Take note Leo Bodnar is a Mac supporter and USB developer. http://forum.microchip.com/tm.aspx?m=276818 And then I read his reply in the following post from him: http://forum.microchip.com/tm.aspx?m=271023&mpage=2&key=񅦋 I am no longer sure whether Mac OS X USB implementation is any better. And I think Dario has the same feeling. Xiaofan -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist