display position of an object with UDP conection

[jgk]

Hi!

New to CPN, so might be asking a stupid question...

I m a trying to display the position of an object (a mini ROV) in open CPN.

I ve set up a connection to receive NMEA data through UDP. It appears to receive the data (data streams showing in NMEA debug window), but then i can't manage to get a display of this position in the map.

any ideas?

Thanks!

[nohal]

No, no idea as we do not know what data your object sends.

[bcn]

Publish the data stream here, in oder to see if it is correct.
(For attachments the paper clip, rename the file to ...txt.jpg to overcome size restrictions - or just paste some lines into the comment)

[jgk]

Thanks for the replies!

See example of the data stream here and attached:


----------
$GPGGA,121555,6326.539,N,01025.447,E,0,00,0.0,0.0, M,0.0,M,,*7B
$GPGGA,121555,6326.540,N,01025.449,E,0,00,0.0,0.0, M,0.0,M,,*7B
...

[nohal]

Originally Posted by jgk

Attachment 168640

Thanks for the replies!

See example of the data stream here and attached:


----------
$GPGGA,121555,6326.539,N,01025.447,E,0,00,0.0,0.0, M,0.0,M,,*7B
$GPGGA,121555,6326.540,N,01025.449,E,0,00,0.0,0.0, M,0.0,M,,*7B
...

Whatever creates this NMEA stream reports all the positions as invalid (0 in the 6th data field, for a valid position it must be 1 or 2, see GPS - NMEA sentence information)

Pavel

[jgk]

Hi pavel,

Thanks for your input. indeed, correcting the NMEA stream with the valid positions fixed it.

And next follow up question: is it possible to display 2 positions from two such streams for 2 different ship (in my case one ROV + one vessel position)?

If I setup two connections with their own data streams of positions, they are interpreted as "own ship" and the ship keep jumping around from one to the other :-)

[nohal]

Originally Posted by jgk

Hi pavel,

Thanks for your input. indeed, correcting the NMEA stream with the valid positions fixed it.

And next follow up question: is it possible to display 2 positions from two such streams for 2 different ship (in my case one ROV + one vessel position)?

If I setup two connections with their own data streams of positions, they are interpreted as "own ship" and the ship keep jumping around from one to the other :-)

Yes, but not like this, the GPS sensor in NMEA0183 means "my own GPS sensor" for us. You will have to use other features - either AIS (AIVDM sentence, "difficult" to encode) or WPL sentence treated as APRS position reports (trivial to encode).

[jgk]

ok, understood, thanks!

indeed, GPWPL will do the trick for me.

[nohal]

Originally Posted by jgk

ok, understood, thanks!

indeed, GPWPL will do the trick for me.

Do not forget to enable it in Toolbox->Ships->AIS Targets...

[jgk]