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[cgreen]

Originally Posted by cgreen

Pavel, that is exactly what I need. Thanks very much for the help. Chris.

Should the WPL message be a simple GPWPL as follows...

$GPWPL,3015.078,N,09851.016,W,TESTWPT*\n

...Or a slightly longer message format, like the kenwood implementation...

$PKWDWPL,011238,V,3015.078,N,09851.016,W,61,180,14 1214,000335,7NAN-9,/P*\n

Even with "Treat WPL sentences as APRS position reports" enabled, and checking that WPL message is arriving ok using connection NMEA debug, I don't get any new waypoints displayed. Chris

[Hakan]

cgreen
OCPN decode a WPL sentence like this:
//** $--WPL,llll.ll,a,yyyyy.yy,a,c--c*hh<CR><LF>
The c--c says the name could be no more than four characters but what I can see in OCPN code any length will do.

In your example above the checksum is missing. It should be like this:
$GPWPL,3015.078,N,09851.016,W,TESTWPT*16<CR><LF>
(I used NMEA MTK checksum calculator)
You could try to make the "Control checksum" unchecked in options>connections but I've never tried if that works.
Here's one method to calculate the checksum if your into programming:

for (p = sentence; *p; p++) {
    checksum ^= *p;
}
where sentence = e.g. "GPWPL,3015.078,N,09851.016,W,TESTWPT"

Håkan

[cgreen]

Originally Posted by Hakan

cgreen
OCPN decode a WPL sentence like this:
//** $--WPL,llll.ll,a,yyyyy.yy,a,c--c*hh<CR><LF>
The c--c says the name could be no more than four characters but what I can see in OCPN code any length will do.

In your example above the checksum is missing. It should be like this:
$GPWPL,3015.078,N,09851.016,W,TESTWPT*16<CR><LF>
(I used NMEA MTK checksum calculator)
You could try to make the "Control checksum" unchecked in options>connections but I've never tried if that works.
Here's one method to calculate the checksum if your into programming:

for (p = sentence; *p; p++) {
    checksum ^= *p;
}
where sentence = e.g. "GPWPL,3015.078,N,09851.016,W,TESTWPT"

Håkan

Thanks Hakan. I took your advice, and made sure I included a calculated checksum. -Made sure to check it using the MTK site. I can see my WPL message arriving ok in serial debug, but I cannot get opencpn to plot the waypoint that it contains. Spent time trying different settings in AIS tab. No luck so far, but not giving up yet. I am using the latest opencpn version 4.4.0 Build 2016-05-31. Chris

[bcn]

The WPL APRS option is enabled?

[cgreen]

Originally Posted by bcn

The WPL APRS option is enabled?

Yes, WPL APRS option is enabled. Chris

[cgreen]

Using python, I have sent WPL message via regular serial port, virtual serial port, and both TCP and UDP network connections, just in case it makes any difference. In all cases I can see my WPL message appear in the nmea debug window. I can only guess that opencpn is looking for something else to be present before it does anything with a WPL message. I do have GPS interfaced, so it is navigating ok when receiving the WPL. Chris

[Hakan]

Chris
I've never tried this so it's may be time for to make a test. You're coming up with a lot of funny new things.
Let's if I can figure this out, or if anyone else has worked on this and can advise?
But short from the code:
Lat and long shall be in format you've used.
But it may be the WP name shall be numbers i.e. integer.
Then O shall give the point a MMSI number based on the name. A made a very quick test but couldn't get it to work. I'll continue but I'm bit busy for the very moment.
Håkan

[Hakan]

Chris
Another short test and found my bug.

I'm sending this sentence: $IIWPL,5321.9705,N,610.3062,E,118*6a where the WP number is updating for every new message 10 sec in between. But it's ok to combine text and numbers.
Looks like this:

[Hakan]

Chris
I'm not sure of your intentions to create WPL>>APRS marks but be aware off that in OCPN they will appear as other AIS targets and will be marked lost and eventually deleted after certain times since last position update. The timer settings are in options>ships>AIS_target.
Håkan

[cgreen]

Originally Posted by Hakan

Chris
I'm not sure of your intentions to create WPL>>APRS marks but be aware off that in OCPN they will appear as other AIS targets and will be marked lost and eventually deleted after certain times since last position update. The timer settings are in options>ships>AIS_target.
Håkan

Yes, that will be fine if they are eventually deleted. I have never managed to get an APRS green square to display yet, so I am at a bit of a dead end. My message checksum is good, my message format follows your example (and many other variations that I have tried), my lat/lon is good and valid, I see message appear ok in debug, but no green square displayed. I tried loading a chart just in case that makes a difference, but no. From a deep dig into documentation, I don't think any additional plugin is needed for this (though I did try the AIS radar display, just in case it helped).

[Hakan]

Chris
This is core OCPN and no plugins are needed.
Try my messages I saved to a file while sending to O. They showed up.
Play it slowly with VDR player pi for example.
They locate marks in the Netherlands. Use AIS target list to find them.
Håkan

[cgreen]

Thanks. I will try that first thing tomorrow morning. Chris

[cgreen]

Originally Posted by Hakan

Chris
This is core OCPN and no plugins are needed.
Try my messages I saved to a file while sending to O. They showed up.
Play it slowly with VDR player pi for example.
They locate marks in the Netherlands. Use AIS target list to find them.
Håkan

Hakan, your example messages worked fine! ...And when I had zoomed out enough and scrolled around the globe, sure enough I found those points, along with a few of my own test points from previous attempts

It appears that ocpn is plotting all longitudes to the East of 0 deg, so my messages that had W where actually being scattered across Europe.

I found a work around, by placing a negative sign in front of the degrees longitude, so the example below now appears in the middle of the Gulf Of Mexico, which is where I was looking.
$IIWPL,2455.0711,N,-8956.0112,E,WP1*76

Thanks to yourself and the kind folks on here who steered me to get this working. Perhaps when you get a moment you could check my findings.
Chris

[Hakan]

Chris...
Very good. And thanks to your diligence you have come to a solution, great!
And thanks for finding the west hemisphere bug. I can see in the source code what's wrong. It's actually the same bug for south. I'll try to fix the WPL sentence decoding and get it to the source for next beta.
Håkan

[stn92]

Hi, i am very new to software development and added some new functionality to openCPN. It`s advanced real size vector icon, that includes 20 and more points to draw realistic ship shape. But my thesis advisor said that i need to develop plugin and not edit origanal openCPN code. I do not know where to start. How to realize such functiolality with exteranal plugin?