Rockbox Technical Forums

Support and General Use => Hardware => Topic started by: Packgrog on July 19, 2010, 09:08:19 AM

Title: 1350mAh battery support for iPod Photo
Post by: Packgrog on July 19, 2010, 09:08:19 AM
I installed the following battery into a 30GB iPod Photo over the weekend:

http://eshop.macsales.com/item/Newer%20Technology/BIPOD1350MPH/

I charged it for 8 hours before installing Rockbox.  I went through the list of battery options, and the options maxed out at 1200mAh.  Is that an adequate setting for a 1350 mAh battery for accurate charge level display, or should more options be added?  Does it make a difference to how Rockbox handles power management, or is it only important for displaying the charge level?

Out of curiosity, is battery life under Rockbox still lower than it was under the regular iPod software?  I've only used Rockbox on the iRiver H120 up to this point, but wanted to try it out on an iPod my mom no longer wanted to use.  I'm loving it, no question, but am uncertain of the battery life, and if there's anything I can do to improve it.
Title: Re: 1350mAh battery support for iPod Photo
Post by: gevaerts on July 19, 2010, 09:10:34 AM
Does it make a difference to how Rockbox handles power management, or is it only important for displaying the charge level?

It doesn't make any difference for power management. It actually also doesn't make any difference for the shown charge level, only for the remaining runtime estimate.
Title: Re: 1350mAh battery support for iPod Photo
Post by: torne on July 19, 2010, 09:36:02 AM
As far as I know we should be about equal or better on all iPods these days. My iPod Video (with my settings) lasts for ~4 hours longer in Rockbox than in the OF :)
Title: Re: 1350mAh battery support for iPod Photo
Post by: Alexannino on August 26, 2010, 04:51:21 PM
As far as I know we should be about equal or better on all iPods these days. My iPod Video (with my settings) lasts for ~4 hours longer in Rockbox than in the OF :)

I also have iPod Video, can you give me yours settings, please?
Title: Re: 1350mAh battery support for iPod Photo
Post by: torne on August 26, 2010, 05:00:05 PM
See http://download.rockbox.org/daily/manual/rockbox-ipodvideo/rockbox-buildch8.html#x11-1430008.4 and turn on "Sleep (after backlight off)", so that it will turn the LCD screen off entirely when it's not being used, instead of just the backlight.

That's the only setting that makes a really big difference to battery life, if you use cheap codecs like MP3. If you use an expensive codec, turning off DSP effects (like the equaliser, crossfeed, etc) will help too, but there's plenty of CPU time free to do these effects with MP3s.
Title: Re: 1350mAh battery support for iPod Photo
Post by: Alexannino on August 26, 2010, 05:07:53 PM
See http://download.rockbox.org/daily/manual/rockbox-ipodvideo/rockbox-buildch8.html#x11-1430008.4 and turn on "Sleep (after backlight off)", so that it will turn the LCD screen off entirely when it's not being used, instead of just the backlight.

That's the only setting that makes a really big difference to battery life, if you use cheap codecs like MP3. If you use an expensive codec, turning off DSP effects (like the equaliser, crossfeed, etc) will help too, but there's plenty of CPU time free to do these effects with MP3s.

You mean on MP3 320kb/s I can put more effects than only Bass 6 and this do not eat my battery?
Title: Re: 1350mAh battery support for iPod Photo
Post by: saratoga on August 27, 2010, 03:59:57 PM
See http://download.rockbox.org/daily/manual/rockbox-ipodvideo/rockbox-buildch8.html#x11-1430008.4 and turn on "Sleep (after backlight off)", so that it will turn the LCD screen off entirely when it's not being used, instead of just the backlight.

That's the only setting that makes a really big difference to battery life, if you use cheap codecs like MP3. If you use an expensive codec, turning off DSP effects (like the equaliser, crossfeed, etc) will help too, but there's plenty of CPU time free to do these effects with MP3s.

You mean on MP3 320kb/s I can put more effects than only Bass 6 and this do not eat my battery?

Depends how many you turn on, but probably using just a few effects will not have much effect on battery. 
Title: Re: 1350mAh battery support for iPod Photo
Post by: torne on August 27, 2010, 04:08:20 PM
The simple bass/treble controls should use no measurable extra power at all because those are hardware tone controls, and so take up no CPU time. The actual 5-band graphic equaliser, the crossfeed, etc are the things which take up CPU time, and unless you turn absolutely all of them on at once there is very little chance that it will affect battery life on MP3 playback. On more expensive codecs such as Ogg Vorbis, each software effect enabled will have a very slight (but real) impact on battery life.

However, no matter what you do, battery consumption is typically dominated by 1) how much time you spend with the backlight on 2) how much time you spend with the LCD on and 3) how often it has to access the hard drive to rebuffer. The first two are controlled by the display settings, and the third is affected by which codec you use (obviously less music can be buffered with FLAC than with MP3), and also by whether you change your mind about what you're listening to (rebuffering different music costs power, and also changing your mind typically involves turning the LCD/backlight on as well so you can see what you're doing ;)