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I have my Pi and a USB powered external hard disk. I am looking for a way just to have one plug for the both of them. At the moment my Kindle Charger doesn't have adequate power to power them both.

My question is:

If I got a larger power supply would the pi be able to give full power to the usb port for the external hard disk? Otherwise, is there a way to power both with just one power supply?

My pi is one of the first models.

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up vote 4 down vote accepted

You just need a supported powered USB hub. This is how I power my Pi. I have a 4 port USB hub. Connect one of the ports to the Pi's power connection. Then connect one of the Pi's USB ports as the source for the USB hub. Then you can use the remaining ports to power things like your hard drive.

I hope that explanation makes sense, you end up with this weird circular thing that works.

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How does this work? the pi needs 700mA, but the max USB 2.0 can give is 500 mA? Don't suppose you know what hub you are using? – Dan H Jan 8 '13 at 19:26
Here it is. google.com/shopping/product/… – Cory Gagliardi Jan 8 '13 at 19:41
Check out the full list of known working Powered USB Hubs here elinux.org/RPi_VerifiedPeripherals#Powered_USB_Hubs – Cory Gagliardi Jan 8 '13 at 19:42
Thank you, cheers for the links – Dan H Jan 8 '13 at 19:58

Raspberry Pi must be power with a charger which has as output 5V and at least 700mA (I use a 5V and 2A charger and it works perfectly). Anyway, with a larger power supply you can't power up all the devices you connect through the usb ports. In fact, by design, the RPi supplies the onboard usb ports with only 100mA of current. ref. http://en.wikipedia.org/wiki/Raspberry_Pi#Specifications

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