GPS problems, summary
kelvie at ieee.org
Wed Jul 16 21:45:23 CEST 2008
On Wed, Jul 16, 2008 at 12:38 PM, Alasal <info at alasal.be> wrote:
> A summary of everything related to the GPS problem.
> Does the people of Openmoko know the problem?
> - Yes.
> Do they work on the problem?
> - Yes, they are actively searching for a solution.
> What is the problem?
> - The Openmoko Freerunner have a long TTFF with the SD card in the phone.
> So it takes a long time (10min+) before you get your first GPS data.
> Wat is TTFF?
> - This is the time to first fix of the GPS. This is the time the GPS has
> needed to get the first clue on where you are on planet earth. So you have
> to do this only once. After you have a FF (first fix), you can get more
> fixes without any problems with the SD card in the phone.
> So if we have a first fix, the SD card isn't blocking the GPS anymore?
> - yes, the SD card isn't blocking the GPS if we have a first fix. (Some
> people even claim it's more stable)
> Does they have a solution?
> - yes. Their is already a highly alpha software workaround. The software
> just disables the SD card when the GPS tries to get it's first fix They are
> also examine a hardware solution.
> Do we have to return our Freerunners to Openmoko?
> - Probably not, because the software workaround should work too.
> But we can't read of the SD card when the GPS is on?
> - Wrong, you will be able to read the SD card when the GPS is on. You will
> probably not be able to read the SD card when you're starting the GPS (appr.
> 30 sec), because the GPS will only block the SD card when it's searching
> it's first fix. After that you will be able to read the SD card again.
> Is their a better software solution?
> - Maybe. From reading the mailing list, I have understood that half the
> Openmoko team is looking into this bug. All this information is only 1 à 2
> days old and the bug is also young, so I suspect they can finetune the
> software workaround and make it only slowdown the SD card or even better.
> Did Openmoko test the GPS with a SD card in it?
> - yes
> Whey didn't they find it while testing the Freerunner?
> - Because they have to do the tests with a fake GPS signal and with that
> signal it worked. (In a fab you haven't a decent GPS signal) They already
> have modified the test, so it correspond the GPS signal better.
> Summary of the summary:
> You will be able to use the SD card in the same time of the GPS except for
> the first appr 30 seconds. (And that's the worst case, because maybe
> Openmoko can find better hacks/fixes)
> ps: I have read all the mails about the GPS problem, but I'm still human. If
> there is a fault or wrong conclusion in this summary, please let the
> community know.
> Openmoko community mailing list
> community at lists.openmoko.org
Thanks for this. I think I would speak for a lot of people when I say
that this would make a nice candidate to be placed on the Wiki :)
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