OpenCPN jumping map

[kodiakic71]

Thanks for the responses all. For a little context, I've been ambivalent about OpenCPN for the past few years (partly because of this tracking glitch) and relegated it to the back of my wheelhouse. But when an old radar magnetron burned out recently I realized that Open CPN could display my Navico 4G radar data, opening up my Navico MFD for a powerful new radar scanner (TX06-1). This renewed my interest in the app. In fact the radar plugin adds a whole new dimension of utility to OpenCPN and for me anyway, makes it all worthwhile.

To gleason:

Yes I do have two chartplotters, each with their own GPS antenna and both wired to the multiplexer. But I have been careful not to output two position sentences at once, disabling the Standard Horizon chartplotter's output before shifting to the Navico. Both result in the "jumping map" or incorrect position info we are talking about here. Also my heading input, a Si-Tex Compact Vector S (0183) is wired to send only heading data. I do not have an autopilot connected to the system.

For bcn: I've attached a screen shot of the NMEA debug window, and a sceen shot of the track properties that show the position error occurring. Sometimes it is a neat transposing of two characters, this time it was a more serious glitch.

I also recorded a few seconds on my NMEA logger and attached that here. By virtue of you asking for this, I hope that you might be able to see something I can't. If not, then thanks for trying!

Simrad NSS12 Standard Horizon CP150/0183 at 38400 Baud
Shipmodul Miniplex-41 USB
AMEC-Camino Class B AIS
Sitex Vector Compact S 0183 NMEA Compass
Open CPN 4.8.0/Win 10

Thanks - Andy

[rgleason]

Kodiac, Thanks for the thorough response. It's more work, but very helpful.
I am calling this topic GPS Jumping now.

Ran the VDR Player with your file, found some local gps jumping around the dock, then about 1/4 of the way through I found a big jump way off the map. I am trying to locate that in the file now.

Not the answer, but this sentence is outdated I believe.
$GPGLC,9960,,,,,,,,,,,,*75
See GLC here

$GPGLC,9960,,,,,,,,,,,,*75
$GPGLC,9960,,,,,,,,,,,,*75
$GPGLC,9960,,,,,,,,,,,,*75
$GPGLC,9960,,,,,,,,,,,,*75
$GPGLC,9960,,,,,,,,,,,,*75
$GPGLC,9960,,,,,,,,,,,,*75
$GPGLC,9960,,,,,,,,,,,,*75
$GPGLC,9960,,,,,,,,,,,,*75
$GPGLC,9960,,,,,,,,,,,,*75
$GPGLC,9960,,,,,,,,,,,,*75
$GPGLC,9960,,,,,,,,,,,,*75
$GPGLC,9960,,,,,,,,,,,,*75
$GPGLC,9960,,,,,,,,,,,,*75
$GPGLC,9960,,,,,,,,,,,,*75
$GPGLC,9960,,,,,,,,,,,,*75
$GPGLC,9960,,,,,,,,,,,,*75
$GPGLC,9960,,,,,,,,,,,,*75
$GPGLC,9960,,,,,,,,,,,,*75
$GPGLC,9960,,,,,,,,,,,,*75
$GPGLC,9960,,,,,,,,,,,,*75
$GPGLC,9960,,,,,,,,,,,,*75
$GPGLC,9960,,,,,,,,,,,,*75
$GPGLC,9960,,,,,,,,,,,,*75
$GPGLC,9960,,,,,,,,,,,,*75
$GPGLC,9960,,,,,,,,,,,,*75
$GPGLC,9960,,,,,,,,,,,,*75
$GPGLC,9960,,,,,,,,,,,,*75
$GPGLC,9960,,,,,,,,,,,,*75
$GPGLC,9960,,,,,,,,,,,,*75
$GPGLC,9960,,,,,,,,,,,,*75

I am finding
$GPGGA,030944,5746.7263,N,15224.7376,W,1,12,0.60,-7,M,9.8,M,,*6F

Using Notepad++ Search and find all instances in current document.

Search "gga" (30 hits in 1 file)
D:\Data-Juno\Nmea\GPS-Jump-kodiakic71.txt (30 hits)
Line 24: $GPGGA,030942,5746.7262,N,15224.7377,W,1,12,0.60,-7,M,9.8,M,,*69
Line 86: $GPGGA,030943,5746.7262,N,15224.7377,W,1,12,0.60,-7,M,9.8,M,,*68
Line 153: $GPGGA,030944,5746.7263,N,15224.7376,W,1,12,0.60,-7,M,9.8,M,,*6F
Line 199: $GPGGA,030945,5746.7262,N,15224.7376,W,1,12,0.60,-7,M,9.8,M,,*6F
Line 261: $GPGGA,030946,5746.7262,N,15224.7377,W,1,12,0.60,-7,M,9.8,M,,*6D
Line 313: $GPGGA,030947,5746.7261,N,15224.7376,W,1,12,0.60,-7,M,9.8,M,,*6E
Line 372: $GPGGA,030948,5746.7263,N,15224.7376,W,1,12,0.60,-6,M,9.8,M,,*62
Line 425: $GPGGA,030949,5746.7264,N,15224.7376,W,1,12,0.60,-6,M,9.8,M,,*64
Line 484: $GPGGA,030950,5746.7264,N,15224.7377,W,1,12,0.60,-6,M,9.8,M,,*6D
Line 548: $GPGGA,030951,5746.7264,N,15224.7378,W,1,12,0.60,-6,M,9.8,M,,*63
Line 609: $GPGGA,030952,5746.7266,N,15224.7380,W,1,12,0.60,-6,M,9.8,M,,*65
Line 666: $GPGGA,030953,5746.7266,N,15224.7382,W,1,12,0.60,-6,M,9.8,M,,*66
Line 729: $GPGGA,030954,5746.7266,N,15224.7383,W,1,12,0.60,-6,M,9.8,M,,*60
Line 788: $GPGGA,030955,5746.7266,N,15224.7383,W,1,12,0.60,-6,M,9.8,M,,*61
Line 847: $GPGGA,030956,5746.7265,N,15224.7382,W,1,12,0.60,-6,M,9.8,M,,*60
Line 909: $GPGGA,030957,5746.7265,N,15224.7384,W,1,12,0.60,-6,M,9.8,M,,*67
Line 973: $GPGGA,030958,5746.7267,N,15224.7385,W,1,12,0.60,-6,M,9.8,M,,*6B
Line 1026: $GPGGA,030959,5746.7269,N,15224.7385,W,1,12,0.60,-6,M,9.8,M,,*64
Line 1080: $GPGGA,031000,5746.7269,N,15224.7385,W,1,12,0.60,-6,M,9.8,M,,*60
Line 1141: $GPGGA,031001,5746.7268,N,15224.7384,W,1,12,0.60,-6,M,9.8,M,,*61
Line 1200: $GPGGA,031002,5746.7268,N,15224.7381,W,1,12,0.60,-6,M,9.8,M,,*67
Line 1257: $GPGGA,031003,5746.7267,N,15224.7378,W,1,12,0.60,-6,M,9.8,M,,*6F
Line 1325: $GPGGA,031004,5746.7269,N,15224.7377,W,1,12,0.60,-6,M,9.8,M,,*69
Line 1382: $GPGGA,031005,5746.7270,N,15224.7378,W,1,12,0.60,-6,M,9.8,M,,*6F
Line 1439: $GPGGA,031006,5746.7272,N,15224.7381,W,1,12,0.60,-6,M,9.8,M,,*68
Line 1496: $GPGGA,031007,5746.7273,N,15224.7383,W,1,12,0.60,-6,M,9.8,M,,*6A
Line 1558: $GPGGA,031008,5746.7273,N,15224.7384,W,1,12,0.60,-6,M,9.8,M,,*62
Line 1619: $GPGGA,031009,5746.7272,N,15224.7385,W,1,12,0.60,-6,M,9.8,M,,*63
Line 1679: $GPGGA,031010,5746.7270,N,15224.7389,W,1,12,0.60,-6,M,9.8,M,,*65
Line 1730: $GPGGA,031011,5746.7269,N,15224.7391,W,1,12,0.60,-6,M,9.8,M,,*65

$GPRMC,030954,A,5746.7266,N,15224.7383,W,0.0,129.0 ,121217,14.9,E,A*38

Line 44: $GPRMC,030942,A,5746.7262,N,15224.7377,W,0.1,129.0 ,121217,14.9,E,A*31
Line 107: $GPRMC,030943,A,5746.7262,N,15224.7377,W,0.1,129.0 ,121217,14.9,E,A*30
Line 168: $GPRMC,030944,A,5746.7263,N,15224.7376,W,0.1,129.0 ,121217,14.9,E,A*37
Line 218: $GPRMC,030945,A,5746.7262,N,15224.7376,W,0.1,129.0 ,121217,14.9,E,A*37
Line 280: $GPRMC,030946,A,5746.7262,N,15224.7377,W,0.1,129.0 ,121217,14.9,E,A*35
Line 329: $GPRMC,030947,A,5746.7261,N,15224.7376,W,0.0,129.0 ,121217,14.9,E,A*37
Line 386: $GPRMC,030948,A,5746.7263,N,15224.7376,W,0.1,129.0 ,121217,14.9,E,A*3B
Line 439: $GPRMC,030949,A,5746.7264,N,15224.7376,W,0.1,129.0 ,121217,14.9,E,A*3D
Line 498: $GPRMC,030950,A,5746.7264,N,15224.7377,W,0.0,129.0 ,121217,14.9,E,A*35
Line 567: $GPRMC,030951,A,5746.7264,N,15224.7378,W,0.0,129.0 ,121217,14.9,E,A*3B
Line 623: $GPRMC,030952,A,5746.7266,N,15224.7380,W,0.0,129.0 ,121217,14.9,E,A*3D
Line 683: $GPRMC,030953,A,5746.7266,N,15224.7382,W,0.1,129.0 ,121217,14.9,E,A*3F
Line 747: $GPRMC,030954,A,5746.7266,N,15224.7383,W,0.0,129.0 ,121217,14.9,E,A*38
Line 805: $GPRMC,030955,A,5746.7266,N,15224.7383,W,0.1,129.0 ,121217,14.9,E,A*38
Line 861: $GPRMC,030956,A,5746.7265,N,15224.7382,W,0.0,129.0 ,121217,14.9,E,A*38
Line 926: $GPRMC,030957,A,5746.7265,N,15224.7384,W,0.1,129.0 ,121217,14.9,E,A*3E
Line 990: $GPRMC,030958,A,5746.7266,N,15224.7385,W,0.1,129.0 ,121217,14.9,E,A*33
Line 1040: $GPRMC,030959,A,5746.7269,N,15224.7385,W,0.1,129.0 ,121217,14.9,E,A*3D
Line 1097: $GPRMC,031000,A,5746.7269,N,15224.7385,W,0.1,129.0 ,121217,14.9,E,A*39
Line 1160: $GPRMC,031001,A,5746.7268,N,15224.7384,W,0.1,129.0 ,121217,14.9,E,A*38
Line 1217: $GPRMC,031002,A,5746.7268,N,15224.7381,W,0.2,129.0 ,121217,14.9,E,A*3D
Line 1275: $GPRMC,031003,A,5746.7267,N,15224.7378,W,0.1,129.0 ,121217,14.9,E,A*36
Line 1343: $GPRMC,031004,A,5746.7269,N,15224.7377,W,0.3,131.0 ,121217,14.9,E,A*3B
Line 1400: $GPRMC,031005,A,5746.7270,N,15224.7378,W,0.0,131.0 ,121217,14.9,E,A*3E
Line 1458: $GPRMC,031006,A,5746.7272,N,15224.7381,W,0.1,131.0 ,121217,14.9,E,A*38
Line 1514: $GPRMC,031007,A,5746.7273,N,15224.7383,W,0.1,131.0 ,121217,14.9,E,A*3A
Line 1576: $GPRMC,031008,A,5746.7273,N,15224.7384,W,0.2,131.0 ,121217,14.9,E,A*31
Line 1635: $GPRMC,031009,A,5746.7272,N,15224.7385,W,0.1,131.0 ,121217,14.9,E,A*33
Line 1694: $GPRMC,031010,A,5746.7270,N,15224.7389,W,0.1,131.0 ,121217,14.9,E,A*35
Line 1748: $GPRMC,031011,A,5746.7269,N,15224.7391,W,0.1,131.0 ,121217,14.9,E,A*35

ZDA Time and Date - Good

Line 48: $GPZDA,030942,12,12,2017,09,00*49
Line 110: $GPZDA,030943,12,12,2017,09,00*48
Line 170: $GPZDA,030944,12,12,2017,09,00*4F
Line 221: $GPZDA,030945,12,12,2017,09,00*4E
Line 283: $GPZDA,030946,12,12,2017,09,00*4D
Line 332: $GPZDA,030947,12,12,2017,09,00*4C
Line 388: $GPZDA,030948,12,12,2017,09,00*43
Line 442: $GPZDA,030949,12,12,2017,09,00*42
Line 501: $GPZDA,030950,12,12,2017,09,00*4A
Line 569: $GPZDA,030951,12,12,2017,09,00*4B
Line 625: $GPZDA,030952,12,12,2017,09,00*48
Line 686: $GPZDA,030953,12,12,2017,09,00*49
Line 750: $GPZDA,030954,12,12,2017,09,00*4E
Line 807: $GPZDA,030955,12,12,2017,09,00*4F
Line 863: $GPZDA,030956,12,12,2017,09,00*4C
Line 930: $GPZDA,030957,12,12,2017,09,00*4D
Line 992: $GPZDA,030958,12,12,2017,09,00*42
Line 1042: $GPZDA,030959,12,12,2017,09,00*43
Line 1099: $GPZDA,031000,12,12,2017,09,00*47
Line 1163: $GPZDA,031001,12,12,2017,09,00*46
Line 1219: $GPZDA,031002,12,12,2017,09,00*45
Line 1278: $GPZDA,031003,12,12,2017,09,00*44
Line 1345: $GPZDA,031004,12,12,2017,09,00*43
Line 1403: $GPZDA,031005,12,12,2017,09,00*42
Line 1460: $GPZDA,031006,12,12,2017,09,00*41
Line 1517: $GPZDA,031007,12,12,2017,09,00*40
Line 1578: $GPZDA,031008,12,12,2017,09,00*4F
Line 1637: $GPZDA,031009,12,12,2017,09,00*4E
Line 1696: $GPZDA,031010,12,12,2017,09,00*46
Line 1750: $GPZDA,031011,12,12,2017,09,00*47

These are the searches done so far:
GGA, RMC, GLL, GNS, GLC, GTD, GXA, XDA, UBX

[bcn]

Andy...

your input is in the NMEA 0183 V.4.0 format with TAG Blocks.
Those prefixes with the \s:MX25.. indicating the source of the data.

Can you disable sending TAG Blocks and see if this makes a difference?

Or just editing the VDR file to get rid of the TAGs and then replaying in your environment ...

Hubert

[rgleason]

The NMEA0183 with position are
DCN -Decca Position outdated. (0)
GGA - Common
GLL - Common
GLC - Loran, outdated. (30)
GXA - Location and time of transit fix at waypoint (0)
TPC - Trawl position (0)

So the jump has to occur somewhere in GGA and GLL

But I don't see it yet!

[rgleason]

Hubert, would like to learn. In Notepad++ > View > Show symbol > can pick Tab + White space, All characters etc. Have all characters on now.

$GPHDM,57.59,M*3B
!AIVDM,1,1,,A,15NCIrgP00E6DQpQ3rs@9OwD0@Ho,0*04
$SDHDG,57.5,,,14.9,E*3E

Darn it does not show the CR|LN at the end of each line.
What is "Tag Blocks" and how do you know it is Nmea4.0?

Are you using a tool?
Thanks.

[rgleason]

Uploaded to FreeNmea Tools and got this path.

Which looks like it is just random movement around the dock, not the GPS Jump issue.
Why would OpenCPN show the GPS JUMP, but not FREENMEA?

GPS-Jump-Kodiak.txt.doc attached. Remove the ".DOC" please.

[bcn]

Rick..

as you know the NMEA standards are not free nor public and if you license them this includes non-disclosure.

Some public infos about NMEA 0183 4.0 TAG blocks:
https://www.nmea.org/Assets/may%2009...00183_v400.pdf
https://rietman.wordpress.com/2016/0...183-tag-block/

And the ship-modul Andy is using announces the TAGs:
http://www.shipmodul.com/downloads/m...iPlex-3_EN.pdf
That's why I thought he might disable sending the TAG blocks and testing if this makes a difference.

Hubert

[rgleason]

This looks pretty good for Windows.
VisualGPS, LLC

Ben Ellision Panbo, tried & liked this Sailsoft
Sailsoft products feature comparison
Also some free ones NMEA simulator products from Sailsoft

Also Artisense has some programs I have not tried yet for both Nmea2000 and Nmea0183 that work with their products. One or two might read Nmea0183 files and help analyse them.
Media | Actisense
I believe the Nmea and EBL Reader will only work with Artisense time stamped files saved by their software, but I might be wrong about that. http://www.actisense.com/media/?prod...type=downloads

Douwe is using their products and software and last summer I used their Nmea2k-0183 converter for one race. It worked flawlessly once we got it speaking 0183.

Any suggestions would be helpful to all of us!

[rgleason]

VisualGPSView is perfect for the GPS files. Does not do instruments, but it nails the position stuff.

So why is OpenCPN having trouble with this file? Where is the GPS Jump coming from? I have been unable to identify it.
This is where we really need to have a more controllable VDR player, that will allow step by step operation, speed up, slow down, all the controls like the Grib player, with a nmea0183 window included. I believe Mike Rasbats started one awhile ago, but those features are really needed.

I may have to do a 1/2 apology about "loose connections" to Kodiac.. but I am holding back for others findings.

[kodiakic71]

Lots for me to learn here!

So I think I'm hearing (1) to eliminate outdated NMEA sentences DCN, GLC, GXA, TPC and to (2) disable TAG blocks (easy enough in MPX Config). I'll try to get another diagnostic run tomorrow if I can make it down to the boat tonight. Thanks!

[rgleason]

Ok, I've got screenshots of OpenCPN now.

[rgleason]

OK, I wanted to grab the NMEA0183 data at the moment the GPS JUMP occurred, but that OpenCPN FEATURE has COMPLETELY DISAPPEARED NOW!!!!

THIS IS REALLY BAD NEWS. WE NEED IT BACK!!
I am forced to close Options to get the VDR file playing, in order to get the toolbar icons to show. Once that is done the Nmea Debug window shows, but I cannot copy the nmea data!!

Here is the moment that the GPS JUMP occurs. Data is scrolling up from the bottom. So start at the bottom looking for the problem.

[bcn]

Rick..

search algorithm:

cut the upper part (file at half) and try...
Upper and lower

And so on to get the offending sentence.

[rgleason]

Hubert, I cant't even copy the area I have isolated at the culprit area (see below) from the Nmea Debug window. --It is impossible and no longer works!!!!

Anyway I think it is this sentence now, based on looking at my screenshots taken directly after the GPS Jump and looking carefully at the debug window in the screenshot this sentence is possibly the culprit.

Line 107: $GPRMC,030943,A,5746.7262,N,15224.7377,W,0.1,129.0 ,121217,14.9,E,A*30

Now I am going to try just playing that.
WE NEED A MUCH IMPROVED TOOL, RATHER THAN DOING ALL THESE GYMNASTICS!

Ok, I stopped VDR immediately while watching for it to happen again.
(We need to be able to pause or stop the reading of the file, then be abble select/highlight a sentence in the nmea debug window and then be able to send it directly to OpenCPN to test the sentence and see what happens.)

[rgleason]

VDR player needs to have a window, where you can paste a nmea sentence in and then push a button to send the sentence! (of course when the Player is stopped).

This business of making a txt file with the sentence and then loading it with VDR player is archaic.

OK, now i have is narrowed down to the GPS Jump offset occurs when I play this file.
---
GPS-Jump-File-Test-A.txt

!AIVDO,1,1,,,B5O9p80005ATwH8@vh1B0TEUkP06,0*5F
$SDMTW,5.3,C*32
$GPHDT,72.35,T*36
!AIVDO,1,1,,,B5O9p805ATwH8@vh1B0TEUkP06,0*5F
$SDHDG,57.3,,,14.9,E*38

Now it is narrow to happening when this file is played.
GPS-Jump-File-Test-B.txt

Which is Line 105 of the file GPS-Jump-Kodiacic71.txt.doc

!AIVDO,1,1,,,B5O9p80005ATwH8@vh1B0TEUkP06,0*5F

I thought AIVD was just supposed to be other ships AIS!!!
THIS IS PROBABLY CORRUPTED.

I then pasted the sentence
!AIVDO,1,1,,,B5O9p80005ATwH8@vh1B0TEUkP06,0*5F

Into Nmea Free
NMEA Decoder. Using this free tool you can decode (parse) your NMEA log.

and Parsed it this is the result!

Unknown or incorrect NMEA message type: !AIVDO,1,1,,,B5O9p80005ATwH8@vh1B0TEUkP06,0*5F.

I think OPENCPN should be rejecting these bad sentences!