GPS - Decode event not firing

[daveo84]

I've been trying to have a GPS_Decode event fire now for nearly a day...Using the examples listed on the homepage (downloads section/gps example) I've tried connecting a GPS (Delorme Earthmate) to the Serial Port, two freeware GPS simulator devices (from another PC to this PC). And Testing on a pocket PC. All of them connect and receive data but the event doesn't fire. I've been very mindful of the port settings/baud rate/ etc.

I know it is connecting because I receive values for Serial.Inputstring when I'm debugging. GPS.tostring returns Decode_GPS.GPS or something like that...(I've been up for nearly 22 hours now straight and am going to go take a nap). I also made sure the Sub Functions were names appropriately and coincide with the GPS varialbe name.


Thanks in advance for any help!

[agraham]

Originally Posted by daveo84

I've been trying to have a GPS_Decode event fire

The name of the event is actually "GPSDecoded", are you using the correct Sub name? Your event Sub should be called "Sub GPSobjectname_GPSDecoded".

[daveo84]

Exactly as it show in the examples.... I get the same problem running them as is without altering any of the Sub names. I am also making sure all of the objects are created and appropriate libraries have been added.

[agraham]

Build up successive Serial.InputString contents in a multi-line textbox or a string for a MsgBox and have a look at it. The GPS library wants a GPRMC sentence terminated by a Cr and Lf and a GPGGA sentence also terminated by Cr and LF in its buffer before decoding it. Check you are getting both of those.

[daveo84]

Ok, so I made sure the line feeds and the returns were in the nmea data. I also watched the serial.inputstring and the data was exactly the same as the output from the sim we're using (Skylab GPS Simulator). It just sits there taking in the data and never gets beyond that.

How long should it take before this event happens?

[agraham]

Originally Posted by daveo84

How long should it take before this event happens?

It is fired by GPS.GPSStream(Serial.InputString). GPSStream fills a buffer appending successive strings passed to it and as soon as the buffer contains both sentences I specified above it parses the data and fires the event then clears the buffer for the next data.

PS. "GPRMC" and "GPGGA" must be uppercase.

[daveo84]

Hmmm,

I'll have a look again, I literally let it run for 10 minutes and still nothing. Both using Delorme Earthmate (actual GPS) and the simulator (figured I'd take out any issues of reception, etc). I've made sure the parity, baud rates, com specs on both ends, and all of the appropriate settings are correct.

Thanks for the help.... I'll report back !

[daveo84]

The following is a literal example of the data I get coming through the serial.inputstring:

Except the Lf & Cr show up as □ in the code. (would this make a difference? ex: $GPGGA,021249,0000.0000,N,00000.0000,E,1,5,1.0,200 0.0,M,0,M,,,,0000*66□□)

$GPGGA,021249,0000.0000,N,00000.0000,E,1,5,1.0,200 0.0,M,0,M,,,,0000*66

$GPGSA,A,3,01,02,03,04,05,,,,,,,,8.3,4.2,7.2*3B

$GPRMC,021249,A,0000.0000,N,00000.0000,E,0,0,01100 8,,,A*74


It does take quit a while for the string to append a new line (3 lines took 90 seconds or so).

STILL NO DECODE TRIGGER

[Erel]

Can you please save the data received to a file and upload the file?
You should save GPS.GPSBuffer to a file after several minutes.

[daveo84]

Will do tommorow. Also I moved the example code to a pocket pc w/ windows mobile 6.1 and ran it there. No data was received from the buffer/inputstring. This was tested in a working environment (The system GPS was working fine and I had altered the code to fit the specific baud rate, port etc.)


Thanks again!