some questions before buying FreeRunner

Al Johnson openmoko at mazikeen.demon.co.uk
Wed Jun 10 18:46:40 CEST 2009


On Wednesday 10 June 2009, a dehqan wrote:
> In The Name Of God
>
> Thanks fro every body attentions ;
>
> another important question ;
> Is this
> PDF<http://people.openmoko.org/joerg/GSM_EMI_noise/big-C_rework_SOP_rc2.pdf
>>enough to fix buzz ?

That is the procedure to buzz fix the FR, yes.

> >>> 3-Can other car chargers be used to charge FR ?
> >>>
> >>>Yes, but you need to tell FR (software) to start the charging
> >>
> >> So e.g nokia car chargers jack is the same as FR car charger ?
> >
> > FR has a standard mini-usb receptable.
>
> So ,almost all chargers do not have usb jack ... If charger output voltage
> was the same can we add usb jack to charger ?

The FR needs 5V, preferably at 500mA or 1A. If your charger can supply that 
then making a jack adapter won't be a problem. Do NOT use a charger supplying 
>5.5V as it will probably damage the FR. If your charger can give 1A then when 
making the adapter you can put a 47k resistor between pin 4 and ground on the 
mini-B connector. That lets the FR identify it as being able to take 1A so it 
will automatically start charging at the full rate.

Car USB adapters are widely available though, and the USB mini-B connector is 
used by a numer of phone manufacturers now. There were reports in the wiki 
from people using TomTom and Motorola car chargers IIRC. The only problem you 
may have is that there was no standard for the use of the ID pin (pin 4) so 
the current capability may be incorrectly detected.



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