GPS problems, summary

Ken Restivo ken at restivo.org
Thu Jul 17 09:20:43 CEST 2008


Not the greatest bit of WIKI formatting, but it's there at least and linked from the GPS page:

http://wiki.openmoko.org/wiki/GTA02_GPS_Problems

-ken
----------
On Wed, Jul 16, 2008 at 11:49:43PM -0700, Justin Wong wrote:
> Great post.  Maybe you can put it on the wiki somewhere, so it's
> visible to more people.
> 
> Cheers!
> Justin
> 
> 
> 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
> > http://lists.openmoko.org/mailman/listinfo/community
> >
> >
> _______________________________________________
> Openmoko community mailing list
> community at lists.openmoko.org
> http://lists.openmoko.org/mailman/listinfo/community




More information about the community mailing list