Reason for GPS problems found! / more patches

AVee openmoko-comunity at
Fri Jul 25 00:42:52 CEST 2008

On Tuesday 22 July 2008 05:43, Simon Matthews wrote:
> > So the fact you were OK at drive level 0 should mean are able to use SD
> > card how you like without problems from SD_CLK to GPS any more.
> Surely the hardware and software 'fixes' can only be seen as a total fix
> if they make the SN (signal to noise ratio) of the GPS the same as if
> the SD card is not present. I would have thought that each of these
> modifications would improve the SN ratio but would not make it the same
> as not having the SD card present.
> I know it is hard but it would be nice to get some figures on how each
> of these modifications by themselves and together effect the SN ratio.
> It might turn out that the software clock drive solution by itself is as
> good as or better than adding the capacitor, and adding the capacitor
> does not improve the SN ratio any further once the clock drive mod is
> done, which would make it unnecessary.

I haven't modded the hardware, but it do use the software fix. With the fix 
the GPS works great, I can't notice any difference with or without the SD 
card present. That is, as long as the SD card is idle, if you start hammering 
the card you will at least lose some precision. Inside my house I generally 
loose the fix when the SD card is stressed, not sure what will happen 
But that's only when really hammering the card, incidental usage does not seem 
to affect the GPS performance in any way.


You know the great thing about TV?  If something important happens 
anywhere at all in the world, no matter what time of the day or night, 
you can always change the channel.
  -- Jim Ignatowski

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