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Tips and questions relating to the GPS modules from SFE
By RancidWannaRiot
#17028
hello,

so i got my board.. connected it.. windows found a device, but couldn't set it up properly.. i tried to let windows look for drivers on its own.. it found something.. installed it.. but it appears that nothing changed..

I also downloaded the FDTI drivers that are linked in the spark fun description page of the em406 USB eval board.... i click on that .exe file that comes with the driver.. and well.. it gives me an error that i can't run it..

so.. umm what should i be doing??

thanks
By RancidWannaRiot
#17030
Okay, i figured it all out.. however..

i can't get a lock on any satalites.. the GPS led just stays on.. it doesn't flash indicating that it has no fix..

is it just my location?

does this thing work well indoors??

i would move my location.. but i can't at the moment
By RancidWannaRiot
#17033
hummm.. so i went outside of my apartment.. stood outhere for about 5 minutes.. i can't get a lock on anything..

i'm getting data from the unit.. but all the data it would get fro mthe satalites.. like longitude.. lattitute.. i'm not getting anything.. and like i said.. the LED stays on....

am i just in a bad locatin.. cause if i am.. this sucks ***.. cause this is where i want to work on this GPS unit...

bleh..

what do you guys think?
By RancidWannaRiot
#17036
bleh.. i'm starting to think this thing is defective....

is there anything i shoudl be doing?? anything other than just plugging it in?

i think tomorrow i'm gonna go drive around with this thing.. see if i can get a fix on something.. but i don't know.. i doubt that will work.. i always have this kind of luck.. lol.

thanks...
By daemondust
#17037
Can you run SiRF Demo, switch to SiRF Binary mode, and see if you're getting any signals at all? Are you surrounded by very tall buildings or trees?

It takes less than a minute for me to get a fix inside.
By mifi
#17048
Hello,

could someone confirm this?

I found out that the LED is flashing in case of no fix.
But if the position fixed, the LED is on.

Regards,

Michael
By RancidWannaRiot
#17058
Whn i switch to the sirf protocol.. i get nothing in debug view..

i get something in the signal and radar views.. i get nothing in the map view.. in the radar view i get two little pictures.. but that's it...

in the NMEA mode.. i get nothing in the radar view or singnal view.. or map view.. in the debug i get some data.. but no location data

it has lat: n/a lon : n/a it.. pretty much has nothing. it does showthe GPS time.. but it appears wrong.. it doesn't match the time here... it's completly wrong.. the mintues aren't even right..

here's an example of data i get in the NMEA protocol..

$GPGSA,A,1,,,,,,,,,,,,,,,*1E
$GPGGA,145508.917,,,,,0,00,,,M,0.0,M,,0000*54

there area few trees.. but not a lot.. no tall buildsing around
By RancidWannaRiot
#17059
UPDATA:

okay this is weird..

so i just left the thing plugged in.. went off to do a few things.. came back and the LED is blinking..

and now i'm getting data... it's weird.. because last night i would leave it alone for like 10 minutes.. and it would never get a fix...

why is it doing it now??

i still get some missing data.. but that could be normal..

it is giving me locatin data now though..

and it's telling me i'm connected to 5 satalites now...

so.. umm.. anyone have a clue as to why it was acting weird??

and.. as i type this.. it just stopped.. and now it's not locked to anythign anymore..

maybe it is my location?? bleh.. lol..
By RancidWannaRiot
#17060
now.. i cna't read the thing anymore.. i'm setting it to 4800 baud.. and i'm not getting crap in NMEA mode.. and i cna't switch to the sirf protocol...

huumm okay. so the baud rate some how changed...

how am i doing that??
By RancidWannaRiot
#17074
is this normal?

i'm trying to get data from it again.. and now it can't lock on to anything...

is this okay?? i guess i have to try different locations??
By daemondust
#17076
I found out that the LED is flashing in case of no fix.
But if the position fixed, the LED is on.
On mine the LED flashes when I have a fix, and is steady on when I don't.

okay this is weird..

so i just left the thing plugged in.. went off to do a few things.. came back and the LED is blinking..

and now i'm getting data... it's weird.. because last night i would leave it alone for like 10 minutes.. and it would never get a fix...

why is it doing it now??
Assuming you don't have a loose connection somewhere on the GPS, that could be the result of a poor signal combined with a receiver that has out of date information. When first powered on, the receiver only knows where the satellites were when it left the factory, so it takes longer to find where the satellites are now. Once it finds one it should catch up pretty quickly as all the satellites send out approximate locations of the others.
Whn i switch to the sirf protocol.. i get nothing in debug view..

i get something in the signal and radar views.. i get nothing in the map view.. in the radar view i get two little pictures.. but that's it...
That's expected. The signal view box tells you what satellites you're receiving from, and how strong the signal is. The radar box doesn't give much data that the signal view box doesn't. The map view box doesn't update until you click the "Current as origin" button, then it will show you how much the gps position drifts (if the gps isn't moving). It also gives you the gps location, quality of fix, and how many satellites were used.
i cna't read the thing anymore..
Do you mean that you aren't getting any output from the receiver, or that it isn't getting a position fix? If you aren't getting any output from the receiver you can try the "Synchronize Protocol & Baud Rate" under the "Action" menu in SiRFDemo. That should try to set the receiver to SiRF protocol at 57600bps. If that doesn't work, do you get any output if you open the port under hyperterm or something similar? If you get data that looks random it may be set to a different baud rate than you've selected. Try the others. However, that may not be so since the SiRF Binary protocol looks pretty random in hyperterminal.
i'm trying to get data from it again.. and now it can't lock on to anything...

is this okay?? i guess i have to try different locations??
It's odd that you would get a fix, then not be able to get one again. If it isn't too much trouble, try to find a place that has as few obstructions between you and the sky as possible. If, after about 10 minutes, you don't get any fix, I would talk to SFE about a return.
By RancidWannaRiot
#17080
Okay,

so.. it takes forever to get a fix here in my apartment.. but it seems to get a fix after about 5 minutes now.. maybe more..

i can only lock on to 5 satalites.. i checked the coordinates it gave me.. and it was in the neighborhood.. but the datasheet say's its' 10m of accuracy.. i think it was off by like 500m

perhaps it's because i can only lock on to 5??? i hope it gets more accurate.. i'm gonna need more accuracy

other than that.. i think it is working.. i think this location is just alittle lame.. i am gonna try other locations later.. but it appears okay now...