NMEA data stream decoding request... ipaq 6515 problems

dave7101 · Occasional Visitor Joined: Apr 11, 2007 Posts: 3

Hello All,

I'm trying to figure out of a DST patch issued by HP has screwed up my internal GPS on an ipaq6515h. The following is a NMEA log from the gps, it fails to get a fix, or a lock on any sat's. And from the data below you can see that the UTC time and date sentences are totally screwed up (date of mar 17, 2002 for one)

Any thoughts? This has shown up on a few different Ipaq's in recent days/weeks, and im trying to rule in/out issues.

$GPGGA,002951.62,,,,,00,00,0.5,,M,0.0001999,M,0.00048,*5C
$GPRMC,002951.62,V,,,,,,,170302,,*13
$GPGSA,A,1,,,,,,,,,,,,,01,01,01*1F
$GPGGA,002952.61,,,,,00,00,0.5,,M,0.0001999,M,0.00048,*5C
$GPRMC,002952.61,V,,,,,,,170302,,*13
$GPGSV,1,1,0*49
$GPGSA,A,1,,,,,,,,,,,,,01,01,01*1F
$GPGGA,002953.62,,,,,00,00,0.5,,M,0.0001999,M,0.00048,*5E
$GPRMC,002953.62,V,,,,,,,170302,,*11
$GPGSA,A,1,,,,,,,,,,,,,01,01,01*1F
$GPGGA,002954.62,,,,,00,00,0.5,,M,0.0001999,M,0.00048,*59
$GPRMC,002954.62,V,,,,,,,170302,,*16
$GPGSA,A,1,,,,,,,,,,,,,01,01,01*1F
$GPGGA,002955.64,,,,,00,00,0.5,,M,0.0001999,M,0.00048,*5E

roswellgrey · Posted: Wed Apr 11, 2007 8:51 am Post subject:

Well, the GPGSA sentence is showing "mode:fix not available" and
the GMRMC sentence is likewise showing is "mode:fix not available"

So, to me, it looks like the unit has not got a fix and therefore will put out a default, incorrect time i.e. the 2002 date

As , I assume , the iPaq DST Patch is a soft patch, can you not remove the soft patch from the Ipaq, reset , and then see if the problem goes away ?

philpugh · Posted: Wed Apr 11, 2007 9:40 am Post subject:

The $GPGSV sentence shows that there are no satellites in view.

Sounds like something has screwed your setup.

Can you de-install back to a working config?
_________________
Phil

dave7101 · Occasional Visitor Joined: Apr 11, 2007 Posts: 3

I've done a (several in fact) hard reset on the device, and the dst patch has been removed, but given that this is the only change i've done in recent weeks, i think its done something that isn't reversible via hard reset. Given that this is showing up in a few different devices (based on some google searches and checking the hp forums) i still suspect the patch vs. some sort of hardware or config issue.

roswellgrey · Posted: Wed Apr 11, 2007 1:57 pm Post subject:

Nasty

A HardReset should (obviously) return it to its original, clean, working state ( GPS Coverage aside, of course...)

However, Persistant File Storage ( on my old Ipaq its called "Ipaq File Store" ) will still be knocking around, and maybe something in there is causing problems ?

Have you manually cleansed / formatted the Ipaq File Store (or equivalent ) , Hard Reset , and then run Quick GPS to aid the Satfix ?

(this assumes that there is nothing in the persistant file storage area that you want to keep !)

roswellgrey · Posted: Wed Apr 11, 2007 4:01 pm Post subject:

Please don't be offended by such a basic question, Dave , but I have to ask ...

You have been downloading the QuickGPS data updates via GPRS and/or ActiveSync ?

I know it is normally stated that updated data "helps" to get a quicker fix, but in sub-optimal conditions, old data / no data can cause no fix at all ...

dave7101 · Occasional Visitor Joined: Apr 11, 2007 Posts: 3

no offense taken, and yep, tried with recent agps data, flushing the agps data, cold start, warm start... still get the same nmea stream regardless

Also, most recently, i blew away the ipaq file store as well, just to ensure that it wasn't causing the issue to reappear after hard resets... nada.

I've opened an HP support ticket, we'll see what they say i suppose.

philpugh · Posted: Wed Apr 11, 2007 4:28 pm Post subject:

Seeing as you have done many hard resets already....

If you don't need your device for a day or two - try removing the battery for a day (or more if poss). It may cause the internal GPS to "reset" itself.
_________________
Phil

roswellgrey · Posted: Wed Apr 11, 2007 6:48 pm Post subject:

This really smells of a hardware problem, but you would be really unlucky for it to happen at around the time that the DST patch was applied.

Very wierd indeed.

I hope you get it resolved soon, and I would be interested in hearing about the resolution /solution ....

bulkman · Occasional Visitor Joined: Apr 19, 2007 Posts: 1

I have the exaxct same situation on my 6515h. Warranty ended March 30 of course. GPS seems to communicate ok and is passing properly formated strings through com7, but no satellites. I was wondering if it may have been a messed up update from globallocate for the quick gps software that has caused some sort of hardware problem. How many people do you know of that have had this problem? Just a note: I did not apply the DST patch until after I could not get GPS fixes anymore, so I don't think the DST patch was initially responsible. What do you think?

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