Battery runtime on iPod 5,5 gen

[rapster]

Reduced battery consumption on PP5002 targets (iPod 1st/2nd gen and 3rd gen). Now rockbox battery runtime is better than OF, verified on 2nd gen :-)

Great! This is good news! Is there a chance that iPod 5,5 gen will soon have reduced battery consumption too?

Greetings

rapster

[Llorean]

The PP502x targets have different hurdles. It gives us some things to look for, but by no means guarantees that it will discovered soon.

[Buschel]

I also cannot wait the next good news as I saw the progress on 2nd and 3rd generation iPODs the last days!  

[sadffffff]

what was the reason for the improvement? I'd be curious to hear some more about this.

[GodEater]

what was the reason for the improvement? I'd be curious to hear some more about this.

As I understand it, this is how it went down :

1) amiconn took delivery of a 2nd Gen iPod he'd bought on ebay
2) On dumping the flash from it (or the original firmware, I'm unclear on which) and then disassembling the same, he found some hardware routines that were performed during device initialisation that we didn't do before. These routines accessed bits of the Portal Player that are previously unknown to both us, and iPodLinux.
3) Copying these routines into our bootloader, and also figuring out finally how to turn the hard drive off when it's not being used resulted in :

Rockbox using less battery than the original firmware on the all PP5002 targets (which is the 1st, 2nd and 3rd Gen iPods).

[carmenm]

Thanks for the info GodEater, that s a great news(i remember when it happened on H3x0, just crazy ... ). It reminds us how lucky we are to have such talented people behind that project.
I know it doesnt mean anything for the 5,5.5gn but at least it gives hope !

Thanks to everyone

[Buschel]

Is there anything where 5.5-users can help? e.g. back up the OF and hand it over to somebody who is able to disassemble it?

[GodEater]

No - we have more than enough copies of it already thanks.

[blindraccoon]

Rockbox is a complete rewrite and uses no fragments of any original firmwares.

3) Copying these routines into our bootloader,...

If the second quote (from above) is factual, then how does that jive with the first quote (from the website's front page) ?

P.S. I'm nobody, just curious.

[bascule]

My knowledge in this area is minimal, but bootloaders are a slightly different beast.

The actual operating firmware (rockbox.player) is (as much as any open source project can be) entirely brand new.

Bootloaders, however, have to insinuate themselves into the OF bootloader so that it is 'diverted' into running Rockbox. Also, certain hardware initilisations have to take place during boot and where the exact behaviour of the hardware is unknown, the only recourse is to copy the OF's init routines directly into the RB bootloader.

EDIT: Obviously, anyone is free to jump on me here if I am talking out of my backside  

[saratoga]

The power consumption improvements just involving storing two words to hardware registers.  The apple code isn't used to do this, amiconn wrote his own:

http://svn.rockbox.org/viewvc.cgi/trunk/firmware/target/arm/system-pp5002.c?r1=14217&r2=14218

Also, rather then asking about these things, its pretty easy to just look them up.  Theres a log of all changes made on the front page.  You don't have to be a programmer to understand what this one did: "Reduced battery consumption on PP5002 targets".