pi2 USB power - Raspberry Pi Forums

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connecting hdd usb port makes tries starting.
there no schematics available yet, simple check shows board power not connected directly usb. remembering first pi release problem usb powering, pi2 doing again?

usb power on pp27 measurement pad.

my 2.5' usb hdd eats around 1a @ 5v. according usb 2.0 specs, single port can provide 0.5a. rpi follows these specs, won't able power hdd (it depends on type) rpi's usb port. also, maximum current available usb ports on rpi around 0.6a. can double adding max_usb_current=1 config.txt, provided use 2a power supply. reason why such hdds work on desktops or powered hubs because don't follow these usb specs exactly.

need either powered hub (preferably wouldn't backfeed rpi) or external power source usb hdd.


raspberrypi



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