This forum uses cookies
This forum makes use of cookies to store your login information if you are registered, and your last visit if you are not. Cookies are small text documents stored on your computer; the cookies set by this forum can only be used on this website and pose no security risk. Cookies on this forum also track the specific topics you have read and when you last read them. Please confirm whether you accept or reject these cookies being set.

A cookie will be stored in your browser regardless of choice to prevent you being asked this question again. You will be able to change your cookie settings at any time using the link in the footer.

Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Miniplex data to SignalK
(2022-09-23, 11:04 AM)pacma Wrote: The device is configured to send data to the subnet broadcast address, because I have two tablets and one pc that need to read the NMEA data as well and sometimes there is more than one of them connected at the same time.
Is it possible for SignalK to receive the NMEA data sent to the broadcast address?

If SignalK doesn't work for you receiving UDP multicast/broadcast, then you can use KPlex.
KPlex should be able to handle it.
Download BBN Marine OS for raspberry pi

Video of actual installation:

Yes, Signal K can receive broadcast UDP messages.

Yes, you need to restart the server to make connection settings take effect.

Often people have inadvertently configured something else, often OpenCPN, to listen on the same UDP port. Make sure there is nothing there. Use lsof to check:

lsof -i -P | grep 7777

where 7777 is your port number.

With nothing active on the port you can use nc to check that the UDP traffic is actually reaching your server:

nc -l -u 7777
nc -l -u -b wlan0 7777

where wlan0 is the network interface the traffic is supposed to be on. If there is incoming UDP traffic this will print it out.

With SK server running with an active UDP connection configured you can enable debug key
in server log you can see the incoming UDP traffic in the log. This helps to verify that the traffic is reaching the SK server.

You can verify that the server is receiving UDP properly by sending NMEA0183 data manually with nc:

echo '$GPRMC,210230,A,3855.4487,N,09446.0071,W,0.0,076.2,130495,003.8,E*69' | nc -u  7777

and you should see the data in the Server Log (with the debug key active).

(Testing the broadcast address with a single host does not work afaik - at least on a mac listening on a port and sending to the broadcast address does not result in any output.)
(2022-09-23, 05:07 PM)tkurki Wrote: Yes, Signal K can receive broadcast UDP messages....

Thanks for taking the time to answer, much appreciated.

The lsof -i -P | grep 10110 result is:
node      20831   pi   19u  IPv6 29442420      0t0  TCP *:10110 (LISTEN)

The nc -l -u 10110 result is:
there is no traffic coming in

If on this openplotter machine I configure the UDP connection for OpenCPN, it will not receive data as well (if I change to TCP it works).
The openplotter is connected to the router by ethernet cable, instead the tablet that works fine receiving the UDP traffic is connected to the same router via wifi.
On the router I ran tcpdump on both ethernet and wifi and I see the UDP traffic on port 10110 on both interfaces, so it shouldn't be a router issue.

My apologies for being such a dumb on this stuff
It sounds like you are trying to set up a data stream from a MiniPlex device to SignalK. Based on your provided information, it looks like you are on the right track. There are a few things to remember when setting up a data stream like this. First, ensure that the MiniPlex is configured to stream the NMEA data TCP and UDP on port 10110. This will ensure that the data is compatible with SignalK. Next, you will need to create a new stream in SignalK. To do this, go to the Settings page and select the Streams tab. You can add a new stream and select the MiniPlex as the source. Also, if this doesn't work for you, you can find the right answers on
My config:
I use 10120 on Shipmodul miniplex: (I kept SK output on TCP 10110)


And in SK:


Only thing not working:
sending data to Miniplex (e.g. ST Pilot commands)
did not retest lately, but when remember well, it complained port in use

Forum Jump:

Users browsing this thread: 1 Guest(s)