WhoGoesThere - a script for exploring connections

[Antipole]

The Connections tab of the Settings panel includes the option to display NMEA traffic. This is useful but can be difficult to use. Data rushes by. You can pause this stream but then only see a small snapshot of what is happening.

The WhoGoesThere JavaScript provides more useable insights.

It starts by listing the active connections as seen through the plugins API.

It then listens to the traffic for 10 seconds (configurable) and reports.

OpenCPN messages

It displays a list of the OpenCPN messages received since the plugin was started.

NMEA0183 data

It displays one sample of each type of NMEA0183 sentence, prefaced by the count of that sentence type.

On my system I see

Counts	        Sentence
10		$SDDBT,13.88,f,4.23,M,2.31,F
10		$SDDPT,4.23,-0.18,
10		$GPGGA,081055,6212.0259,N,00525.3855,E,1,11,0.78,49.56,M,43.97,M,,
10		$GPGLL,6212.0259,N,00525.3855,E,081055,A,A
10		$GPGNS,081055,6212.0259,N,00525.3855,E,A,11,0.78,49.6,44,,,V
10		$GPGRS,081055,1,0.0,-0.0,0.0,-0.0,-0.0,0.0,0.0,0.0,-0.0,0.0,0.0,,,
12		$GPGSV,3,3,12,11,23,040,41,28,46,213,43,26,41,280,41,09,08,000,39
20		$HCHDM,174.4,M
10		$IIMDA,,I,,B,8.3,C,4.5,C,,,,C,,T,,M,,N,,M
10		$IIMTW,4.5,C
10		$WIMWV,29.26,R,17.26,N,A
10		$GPRMC,081055,A,6212.0259,N,00525.3855,E,0.02,0,230904,,,A,V
10		$TIROT,-1.82,A
10		$IIRSA,0.8,A,,V
10		$IIVHW,,T,174.4,M,0,N,0,K
11		$IIVLW,16223.57,N,16223.57,N,,N,,N
11		$GPVTG,0,T,,M,0.04,N,0.07,K,A
11		$WIVWR,29.4,R,17.3,N,8.9,M,32,K
10		$GPZDA,081055,23,09,2004,,

NMEA2000 devices

If you have an NMEA2000 connection, the script will have sent PGN59904 to all stations, requesting them to send PGN126996. The responses are displayed.

This reveals which devices are on the network and at which address. (Some complex devices have more than one presence and give more than one response for a given address.)

On my system I see:

NMEA2000 stations responding to PGN126996 request
Source ProdCode   ModelId                    SoftwareVersionCode  ModelSerialCode  Certification  LoadEquivalency
0      11369      NMEA 2000<->0183 Gateway ( 1.100, 2.191         115619           0              1
2      6643       NMEA 2000 Wi-Fi Gateway (W x.xxx, 1.084         239208           2              2
3      6643       NMEA 2000 Wi-Fi Gateway (W x.xxx, 1.084         239208           2              2
4      6643       NMEA 2000 Wi-Fi Gateway (W x.xxx, 1.084         239208           2              2
5      2545       Reactor 40                 3.40                 3415516878       2              4
6      17032      GPS17x-NMEA2000            2.80                 3807192399       1              3
7      23020      AIS600                     2.10                 0000001233       1              2
8      10467      GMI10                      3.40                 3805431112       1              6
9      10467      GMI10                      3.40                 3817816629       1              6
10     14190      GWS10                      2.80                 3841963403       1              2
35     14367      DST200                     1.000,1.011          1441531          1              4

The script then lists the PGNs it has seen, including their count and originating address. Using the earlier table, you can see which device is sending which PGN.

ON my system I see

Counts	        Source	         PGN
9		5		61184	Seatalk: Wireless Keypad Light Control
8004		5		126720	Seatalk1: Pilot Mode
20		6		126992	System Time
11		35		126996	Product Information
102		5		127245	Rudder
102		5		127250	Vessel Heading
102		5		127251	Rate of Turn
51		5		127257	Attitude
7		2		127508	Battery Status
10		35		128259	Speed
10		35		128267	Water Depth
9		35		128275	Distance Log
202		2		129025	Position, Rapid Update
82		2		129026	COG & SOG, Rapid Update
20		6		129029	GNSS Position Data
10		2		129033	Time & Date
14		7		129038	AIS Class A Position Report
1		7		129039	AIS Class B Position Report
10		6		129539	GNSS DOPs
10		6		129540	GNSS Sats in View
102		10		130306	Wind Data
21		35		130311	Environmental Parameters
5		10		130312	Temperature
5		10		130314	Actual Pressure
10		2		130577	Direction Data

NMEA2000 data

The script includes the statement

var NMEA2000Decode = false;

If this is changed to

var NMEA2000Decode = true;

then the script will also decode the samples and display them as JSON.
Examples from my system are:

4	127508	Battery Status
{
	"PGN": 127508,
	"id": "batteryStatus",
	"description": "Battery Status",
	"timestamp": 10365030,
	"priority": 6,
	"desination": 255,
	"origin": 2,
	"instance": 0,
	"voltage": "12.4700000"
}
6	128259	Speed
{
	"PGN": 128259,
	"id": "speed",
	"description": "Speed",
	"timestamp": 10365155,
	"priority": 2,
	"desination": 255,
	"origin": 35,
	"sid": 1,
	"speedWaterReferenced": "0.0000000",
	"speedWaterReferencedType": "undefined"
}
6	128267	Water Depth
{
	"PGN": 128267,
	"id": "waterDepth",
	"description": "Water Depth",
	"timestamp": 10365153,
	"priority": 3,
	"desination": 255,
	"origin": 35,
	"sid": 250,
	"depth": "4.5500000",
	"offset": "-0.1800000"
}

The script has its own repository here, where you can find installation instructions.

The repository has a Discussions forum for detailed discussion of it.

NB There are a few issues with the script, which are listed in the repository. Check there before raising new ones.

[Hakan]

Funny tool!
Thanks

[rgleason]

Tony this looks very interesting to me. Why wouldn't it help Users with Connections?

[rgleason]

Tony, I have added it as a resource to the bottom of
https://opencpn.org/wiki/dokuwiki/do...t_whogoesthere

[torrmundi]

Tony,

Very interesting script! I've run it for a variety of N2K, N183 and Signal K sources.

I ran into 1 Limitation (logged on Github):
- Decoding Signal K not supported.

1 issue, don't know the reason, may be Actisense's raw protocol:
- choked on Actisense NGT-1 raw (N2K) output.

1 issue, probably related to not having bi-directional ports setup:
- no response to PGN 126996

1 improvement in display:
- use leading 0's in the message counts to keep vertical alignments, e.g. 001, 023.

Several suggestions:
1. convert counts to rate of messages/second (actually easy in your head since the duration is 10 sec)
2. group messages by function, e.g. Wind, Environment, Steering

[Antipole]

@torrmundi please raise issues for points not already raised there. Thus we can keep track of resolution

Am sailing so there will be delays in responses. .

[rgleason]

Tony, John may not know the drill and details.
John, he is talking about raising the issues here under his repository.
https://github.com/antipole2/WhoGoesThere/issues


I believe you have a git account, right?

[torrmundi]

Rick, yes I have a git account. Looks like Tony created a bug issue associated with YDWG-02 devices.

[Antipole]

WhoGoesThere has been updated to v0.2.
It now listens for SignalK data and displays counts and samples.

Thanks to @torrmundi for help with this.