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ipod 5.5g Sleep mode?

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silentseraph:
well, i mean, thats the point of sleep mode. It doesnt eat up a lot of battery, but its still "on". It just kills the battery to boot it up again and again, and while in school, ill have to turn it off in between classes, which kills it a lot faster than it would If I could put it to sleep. Im not saying that leaving it off takes more power, but booting it up repeatedly just kills it really fast.

grawp:

--- Quote from: silentseraph on September 15, 2007, 05:20:26 PM ---well, i mean, thats the point of sleep mode. It doesnt eat up a lot of battery, but its still "on". It just kills the battery to boot it up again and again, and while in school, ill have to turn it off in between classes, which kills it a lot faster than it would If I could put it to sleep. Im not saying that leaving it off takes more power, but booting it up repeatedly just kills it really fast.

--- End quote ---
you're definitely right.  :)

GodEater:
Again - what are you basing this on ?

AlexP:
I know what sleep mode does and what turning on and off is.  However, you cannot say which takes more power without some measurements and calculations.  You need to do:

Power required to turn off, then on again = x
Power required to stay in sleep = y/min
Minutes in sleep = z

Therefore if z is low enough that y*z < x then sleep is worthwhile, otherwise it is better to turn off then on again.

Just saying you are definately right doesn't mean anything, the only way you can say for sure is by doing some measurements.

Yotto:
And this experiment is impossible to do, as there's no sleep mode to get variable y.

However, we could estimate it I suppose, and it's surely 0 < y < (power consumed while idle, backlight off, not updating the screen).

(The rest of this is on an iPod Video, all I have available to test on.  While the same could be done for all other players, the hard number apply only to the iPod Video, and actually technically only to MY iPod Video)

As far as battery usage for booting, on my iPod 5G Video it appears to be under 1%, possibly around 0.5%, on a battery that's seen over 18 months of nearly daily use, but the iPods tend to report the battery levels strangely right on bootup (At least mine does.  It said 15% right away, and after 30 seconds or so jumped to 24%.  It was this 24%, which shrunk from 26% over 7 reboots, that I used)

I haven't done a battery test lately, but while using the ipod it's around 6 hours from just my noting how much time I've been listening and how much battery is left (something I do moderately often), so I'll use 6*60/100 = 3.6 minutes per percent while running. As I don't tend to leave my ipod on and not playing music, this number is likely low, but by how much I have no idea. Let's say 5 minutes to lose a percent in the lowest mode you could get in without sleep mode.

So, if I'm going to leave my ipod on for more than 2.5 minutes, I'm better turning it off.  That's interesting to me, I frequently pause my ipod for upwards of 30 minutes at work, sometimes hitting that 30 minutes, which is where I have Rockbox set to turn it off.

Can sleep mode do significantly better? 10x better or more?  If it can't do at least 20 times better, you can't make it through an hour class without wasting more battery.

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