Pass NMEA 2000 data to NMEA 0183 Speed and Depth Display

[Rolls FPV]

Hi all, hoping someone can help. 

I have a Raspberry Pi with Pican-M hat with NMEA 2000 Airmar DST810 transducer and GPS connected and an old Stowe Dataline Speed and Depth Display. 

My question is how do i get the data from the NMEA 2000 transducer to the NMEA 0183 display. 

Its all wired correctly and i have the following plugins installed Convert Signal K to NMEA0183, Signal K to NMEA 2000. 

I can see all the data on the Signal K dashboard, but nothing on the Display.

Any help would be much appreciated. 

[pe...@peterpetrik.com]

I also "have a Raspberry Pi with Pican-M hat with NMEA 2000 Airmar DST810 transducer and GPS connected" in my system. I pass NMEA 0183 data to my VHF (GGA, GLL, HDG, RMC). 

Did you go to /admin/#/serverConfiguration/plugins/sk-to-nmea0183 to make the configuration for DBK, DBS, DBT, or DPT? Not sure which of those your Stowe requires. You should be able to verify via the logs that those NMEA 0183 sentences are being generated.

Lastly, be sure to read https://copperhilltech.com/blog/testing-nmea-0183-for-the-picanm-nmea-0183-nmea-2000-hat-for-raspberry-pi/ - Wilfried wrote that after my communication about the PICAN-M hat and the NMEA 0183 connections. 

He said: "I concluded that the confusion is based on a wrong image on the NMEA website. In the wiring diagram, IN+ connects to OUT+ and IN- connects to OUT-, which is wrong, because it does not comply with the EIA-422 (RS 422) Standard. According to EIA-422 TxA (+) connects to RxB (-), and TxB (-) connects to RxA (+). That explains the need for swapping the wires."

All of that refers to the fact that in my setup, based on the above:

What DOES work:
PICAN IN+ to NMEA 0183 device OUT-
PICAN IN- to NMEA 0183 device OUT+
 
and also works:
NMEA 0183 device IN+ to PICAN OUT-
NMEA 0183 device IN- to PICAN OUT+

So there's a need to switch the wires contrary to the labeling in order for the NMEA 0183 devices to work as expected. In my case, that anemometer feeding data into the PICAN-M and VHF consuming the NMEA 0183 output. That's another neat trick that isn't really advertised - the NMEA 0183 input and output do not have to be the same device (if the sending device doesn't require input, or the receiving device doesn't report back).

[Rolls FPV]

how did you setup the nmea 0183 interface on the pi?

[Rolls FPV]

I did everything suggested but im still not seeing data on the display i did cat /dev/ttys0 and im not seeing any data on the serial port. 

On Thursday, June 30, 2022 at 11:48:50 AM UTC+10 pe...@peterpetrik.com wrote:

[Rolls FPV]

I found this on the signalk to nmea0183 github page.

If you want to output the conversion result into a serial connection you need to configure the serial connection in the server's Admin interface and add an extra line to the settings.json, specifying that the serial connection should output the plugin's output:

{ "pipedProviders": [ { "pipeElements": [ { "type": "providers/simple", "options": { "logging": false, "type": "NMEA0183", "subOptions": { "validateChecksum": true, "type": "serial", "suppress0183event": true, "sentenceEvent": "nmea1data", "providerId": "a", "device": "/dev/ttyExample", "baudrate": 4800, "toStdout": "nmea0183out" <------------ ADD THIS LINE }, "providerId": "a" } } ], "id": "example", "enabled": true } ], "interfaces": {} }

but i can not find in my settings.json file anything that looks the same as this.

[pe...@peterpetrik.com]

I don't believe I had to make any changed to the settings.json file.

The relevant section of mine is:

    {
      "enabled": true,
      "id": "0183",
      "pipeElements": [
        {
          "options": {
            "logging": false,
            "subOptions": {
              "baudrate": 4800,
              "device": "/dev/ttyOP_0183",
              "type": "serial",
              "validateChecksum": true,
              "suppress0183event": false,
              "toStdout": [
                "Location"
              ],
              "sentenceEvent": "LCJ",
              "ignoredSentences": [
                "PLCJ",
                "PLCJE85C8"
              ]
            },
            "type": "NMEA0183"
          },
          "type": "providers/simple"
        }
      ]
    }

Screenshots of my serial setup:

And corresponding SignalK data input

[Rolls FPV]

I am currently using the bbsmarine image and it does not have the serial 2.2.3 app installed, you dont know how to install it do you? 

This is what i have in SignalK

[pe...@peterpetrik.com]

Unfortunately, I'm not familiar with bbsmarine setup. It may be worthwhile to spin up an OpenMarine image on a separate SD card and test it that way.

[Rolls FPV]

hi you dont happen to know where i can download the openmarine image from?

[pe...@peterpetrik.com]

https://openmarine.net

https://forum.openmarine.net

[Rolls FPV]

So i finally got kplex installed and setup a get_sk tcp in 127.0.0.1 10110 no filtering and a serial out ttyS0 4800 no filtering  in diagnostics in kplex i can see the data for DBT and DBK on both the TCP in and Serial out but still nothing on the display if i open a terminal and do cat /dev/ttyS0 i get nothing any ideas