SysOnChip BT GPS Hangs

Jem · Occasional Visitor Joined: Jul 26, 2004 Posts: 7

This is my second GPS unit that hung on me. It worked fine for a few days and suddenly one fine day it just refuses to get a fix. Although NMEA strings are received from the unit, but most of it is invalid.

I highly suspect that SysOnChip has got the same problem that has been hounding the Holox users.

I am definitely taking mine back to the distributor to sort out.

BTW. Anyone knows of a way to do a total rest of the unit? Hopefully it will work. I am just crossing my fingers that it is not a problem ala Holux.

Cheers

Dave · Posted: Mon Jul 26, 2004 5:00 pm Post subject:

Are you sure you are not trying to switch between NMEA and SiRF ?

Jem · Occasional Visitor Joined: Jul 26, 2004 Posts: 7

I know what you are refering to, have spoken to the guy who sold me the unit. The unit is definitely in NMEA mode. Even went thorough your tutorial on the GPS viewer software, which is very similar to the one that comes with the SysOnChip GPS.

The only thing that could have probably gone wrong is some of the third party software connecting at other baud rates other than the specified 38400 for the unit.

Will be meeting up with the chap to see what can be done with it. It is definitely not working. Can't get a fix at a location where my old hand held Magellan Spor Track Pro gives 6 satellites at very strong levels of reception.

Hopefully he is able to sort it out.

Dave · Posted: Tue Jul 27, 2004 9:28 am Post subject:

It's quite possible that it's either been switched to SiRF, or that the baud rate has been switched, I would try every baud rate under NMEA to try and connect.

Jem · Occasional Visitor Joined: Jul 26, 2004 Posts: 7

Managed to get a one to one exchange from the supplier here in Singapore. He has got two units that are behaving in this way out of a batch of 100 that he has imported. So i might just have been unlucky twice.

The new one is working very well with very short TTFF times.

Dave · Posted: Wed Jul 28, 2004 7:09 am Post subject:

Our first SysOnChip did die on us, but it wasn't the Bluetooth module (like most BT GPS failures), it was the on-board antenna. Plugging an external patch antenna into the GPS allowed it to work, but we were told that our pre-production model was hand made and not machine made, so no Quality Control had been carried out.

Jem · Occasional Visitor Joined: Jul 26, 2004 Posts: 7

The thing I noticed when I was trying my best to revive both units was, that is was still sending NMEA strings to the PPC. But most of them were not complete.

Secondly I noticed that the UTC time as reflected in the SysOnChip Viewer programme was way off.

Sometimes you are able to get a display of the satellite view, but all of them showing red, but most of the times, the satellite view page was totally blank except for the header and the grid grid ring diagram.

The new unit is working excellently...still keeping my fingers crossed.

Dave · Posted: Thu Jul 29, 2004 8:15 am Post subject:

Hmmm, this sounds like it could be an antenna issue. You won't get a proper UTC time until you have the full 3D fix, but if you are getting corruption in the NMEA string then I'd put that down to the patch antenna.

	PocketGPS
	Web