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When I connect the USB power source, it makes CPU to stay on (even though "Development->Stay awake" is off).

When charging from a weak power source if makes battery to drain even faster than is case of USB power is not connected at all (because of CPU stays on instead of sleeping).

How to stop external power connectedness affecting CPU sleeping policy?

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What do you mean by "CPU stays on"? Are you talking about the screen being on? Or are you using an app to constantly monitor the frequency at which the CPU is running? –  fernio Feb 12 '13 at 23:49
I keep a program that constantly blinks LED when screen is off, so I clearly see when (CPU is on while screen is off). Usually after I press power button to turn off screen, it blinks several times and stops. But when charger is connected it keeps blinking. –  Vi0 Feb 13 '13 at 0:01
The program: brightact (source); usage: brightact /sys/...led.../brightness 20 100000 400000 /sys/power/wait_for_fb_sleep –  Vi0 Feb 13 '13 at 0:14
I'm looking at the source you provided, and it's written in plain C. I'm not sure it's possible to run such a program in Android. Which device are we talking about (maker, model)? Which OS is it running? –  fernio Feb 13 '13 at 13:04
Most of my programs for Android are currently in C, require root access and interfaces the Linux kernel directly (I'm currently more Linux hacker than Android hacker). I'm running Android 2.3 on Sony-Ericcson Xperia X10. –  Vi0 Feb 13 '13 at 13:32
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