thoughts on A-GPS offline

[mqy]

I've verified the issue on GPS receiver in GTA02:

When dump ALM/EPH messages, in several messages, fields follow SV ID field
in payload are filled with zeros.


Daniel Willmann wrote:
> 
> On Sun, 1 Mar 2009 14:25:14 -0800 (PST)
> mqy <meng.qingyou at gmail.com> wrote:
> 
>> "
>> UBX-AID-EPH and UBX-AID-ALM Messages for Satellite without valid
>> Orbits When polling UBX-AID-EPH or UBX-AID-ALM messages, satellites
>> without valid ephemeris or almanac data will 
>> return a complete UBX-AID-EPH or UBX-AID-ALM message with all data
>> words set to zero. This doesn’t comply 
>> with the protocol specification. Furthermore, u-blox 5 receivers with
>> firmware V5.00 and earlier can run into a 
>> floating-point exception when fed with such “empty” ephemeris. 
>> "
>> 
>> Is that the cause :D
> 
> Yeah, thought that at first as well, but almanac data was okay at that
> point. The position was not, however. I guess the problem the chip
> tripped over is similar in both cases though.
> 
> Regards,
> Daniel Willmann
> 
>  
> _______________________________________________
> Openmoko community mailing list
> community at lists.openmoko.org
> http://lists.openmoko.org/mailman/listinfo/community
> 
> 

-- 
View this message in context: http://n2.nabble.com/thoughts-on-A-GPS-offline-tp2338403p2415564.html
Sent from the Openmoko Community mailing list archive at Nabble.com.