Raspberry Pi Forums

Hello,

i think about to build a autonomous robot and search for an easy, cheap and low power controller. I read something about 3,5 watt, but it can be decreased by underclocking.

How much can the power usage dropped? What if i need no gpu, usb, sound, lan? I guess i only need gpio/csi.
Possible to turn all other off to save power?

I see at amazon (i am from germany) that there are 2 raspberry offers, looks both Rev. B but with different prices!?
Where is the diff. of these both?

http://www.amazon.de/Raspberry-Pi-RBCA0 ... =raspberry
http://www.amazon.de/Raspberry-Mod-Rev- ... =raspberry

greetz

If you don't need USB, you can cut about a third off the power usage with this trick: (Don't run this unless you know what you're doing)

ShiftPlusOne wrote:If you don't need USB, you can cut about a third off the power usage with this trick:

Code: Select all

echo 0x0 | sudo tee /sys/devices/platform/bcm2708_usb/buspower

(Don't run this unless you know what you're doing)

Wow, USB take 1/3 off the power even nothing is connected!
So i can drop to ~2,3 watt just turn usb off. Thx for the info.

I found that nice info: http://www.daveakerman.com/?page_id=1294
and decide to buy a Rev. A. that uses 1/3 of the power Rev. B takes.

I guess i can live with half of the memory.

igel1974 wrote:

ShiftPlusOne wrote:If you don't need USB, you can cut about a third off the power usage with this trick:

Code: Select all

echo 0x0 | sudo tee /sys/devices/platform/bcm2708_usb/buspower

(Don't run this unless you know what you're doing)

Wow, USB take 1/3 off the power even nothing is connected!
So i can drop to ~2,3 watt just turn usb off. Thx for the info.

Yes, the chip on the B that provides the ethernet and USB hubs is quite thirsty.