Charging/powersupply trouble

[Joerg Reisenweber]

Am Fr  9. Januar 2009 schrieb Finn-Arne Johansen:
> William Kenworthy skrev:
> > On Thu, 2009-01-08 at 23:11 +0100, Finn-Arne Johansen wrote:
> >> Finn-Arne Johansen skrev:
> >> ...
> >>> ...
> >> I charged my GPS battery for some time yesterday (30-60 minutes), and
> >> was able to boot my FR. I connected the FR to my laptop, and the Red
> >> AUX-light came on. I also logged into it, and checked that it charged
> >> the device in 500mA mode. From the log of my DHCP-server, I saw that it
> >> was active for 20 minutes with wlan powered. Then it died. I recharged
> >> the battery in the GPS over night, and tried it this morning. Then it
> >> should have 680 mAh. I turned it on this morning at the office, and from
> >> the dhcp-log , it seems to be up for ~67 minutes, without suspend, with
> >> full backlight on, wlan connected. I think the red light indicated
> >> charging the whole time. But as said - this is not a GTA02 battery, so
> >> maybe the charger fail to charge. but shouldnt it be able to at least
> >> stay on ?
> >> I guess its time to return the device for repair, or ?
> >>
> > What sort of battery is your "gps" battery? - you know that the FR can
> > only charge its own specific battery type? - it will operate on others
> > such as a nokia battery, but wont charge it which is what seems to be
> > happening to you.
> 
> I had som supition in that direction
> 
> > Boot the FR using the substitute battery - once up, plug in the usb so
> > charging is enabled and swap the batteries over live - the FR battery
> > should then start charging.
> 
> The trouble is, as soon as I take out the GPS-battery, the FR dies :(

You should use the OM-wallcharger, and you should disable GSM, and probably 
also disable WiFi prior to swapping batteries. Both may draw more current in 
spikes, than the USB-charging can supply -> FR shuts down due to brownout.

Make sure the wallcharger really charges your FR.
I don't know which version of FR you got, but around xmas it probably should 
be one of the newer ones (with 100uF on Vsys) which don't have any issues 
anymore on booting even without any battery inside. Holding AUX and then 
inserting wallcharger should boot up the device (depending on NAND-bootloader 
version also without AUX it should boot on inserting wallcharger).

AFAIK there shouldn't be an issue with charging non-OM batteries in FR, the 
PMU bat charger circuit is bat-type agnostic, so should be at least 
NOR-uBoot. 

cheers
jOERG
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