Putting Beagle in sleep mode or hibernation

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1

Hello all,

I want to know how can i put my beagle into sleep mode or hibernation
such that i can save some power. Actually i'm planning to run beagle
with solar power. Currently, the power used by beagle is avg 3.5 Watt.
BUt i want to reduce it to 1Watt by putting it to sleep.
The device that i necessarily require are USB based EVDo for net
connection, one more USB based device that takes around 100mamp
Please suggest:
i) How can i go to sleep mode
ii) How can i wake up
iii) Is there any other method to reduce power on beagle

2

Did you able to find the solution for this? :slight_smile:

3

Hello Pradeep,

I found some sort of solution to put beagle in sleep mode. Itis going
well in sleep mode but while waking up it's not able to bring up the USB
ports and unforunatley i didn't get any solution to bring up the usb
without restarting the BB.
My BB version is C3 and i put ubuntu on it. Kernel version which i tried
are 2.6.29 with smartreflex enabled and 2.6.36-rc7 without smartreflex
capability.

I used pm-suspend command to put BB in sleep mode. It can even be done
without using pm-suspend command using the following command:
echo -n "mem" > /sys/power/state
this will put your usb to sleep mode.

One thing i found that smartreflex capable kernel was consuming power
very near to the suspend mode and advantage was this that i was still
able to use USB. But still there was some problem coming after some time
with USB. However, i'm not sure that it's because of smartreflex or some
problem in my power circuitry with which i connected my USB hub..

So try this out and tell me if anything new you find. Also, if anyone
can suggest USB problem solution that i mentioned on top it will be very
helpful.. Thanks in advance.

4

For saving power I have found this thread on disabling the DVI chip.
http://groups.google.com/group/beagleboard/browse_thread/thread/7a13da558a07779b/49979a3ea3201a5c?lnk=gst&q=save+power+echo+0#

As for the second question...
How did you wake up the beagle from sleep mode??

5

For coming out of the sleep i just used to hit any key on the keyboard
which i think used to generate uart interrupt on the beagle and beagle
becomes active.

Did you measure power consumption of your Beagle?? For me it was around
1.5 Watt. I didnt try disabling the DVI chip. I'll try disabling DVI
also.

6

I'm actually using the xM Rev B with Ubuntu 10.10 Maverick. The power
runs idle at 2.8w, and with DVI chip disabled it drops 0.35w which is
a 12.5% savings.

7

It's a great improvement after disabling the DVi. I would try it on my
C3 BB. Let me see how much power i'm gonna save.
Thanks for your tips.