Charging Neo Freerunner via USB port
shawn.t.rutledge at gmail.com
Fri Apr 18 22:08:08 CEST 2008
On Fri, Apr 18, 2008 at 12:06 PM, Michael Shiloh <michael at openmoko.org> wrote:
> > * for hacking purposes it would be good to document what other mfrs
> > chargers use and how easy they are to hack into moko fastchargers.
> > This should be a wiki page and community driven, of course, but you
> > could get it jump-started with whatever info you have on this issue.
> > I, for one, have a small pile of motorola chargers with mini USB on
> > them that I'm more than willing to hack into moko fastchargers given
> > some basic instructions.
> Since I feel the utility of this isn't tremendous, I think my time is
> better spent elsewhere. However, if others want to do this, I would suggest
> you start your search at lady ada's forum where they discuss getting the
> minty-boost charger to work with different models of iPod. That seems to be
> one of the most comprehensive discussions of USB charger identifications I
> have ever found. (If anyone knows of a similar, or better one, I would love
> to hear about it.)
I would like to see the Motorola chargers working too, without having
to modify the charger. It seems that it's some other resistance,
maybe 200k. What is the tolerance? Does the Freerunner actually
measure the resistance? If we modify the code to be more tolerant
(any resistance between 20K and 500K means a charger is being
detected, and 500mA should be OK, whereas if it's 47K we can charge at
1A) could the phone be distributed with this modification? Where is
this code which does the measuring, is it the PMU firmware or it runs
on the main CPU?
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