NMEA multiplex debug

[petter5]

I'm trying to output nmea RMC to a DSC vhf radio, using opencpn's multiplexing but the output seems to be corrupted - see attached screen shoot. In the settings, there is only checked for "forward RMC" - nothing else"

The gps is connected to a 4 port serial to ip nmea converter (transas) and runs at 115200, the plotter with opencpn 4.4 gets the nmea feed from the gps over tcp 10.8.1.10:50000 and works as expected. also the system gets AIS input form a serial ais at 38400 connected to converter and feeds the system with ais 10.8.1.10:50003 - works great ( turned off during trouble shooting so not seen in the debug window)

from the sentences seen in debug, I can see that the GNRMC is forwarded ( the gps is digitalyatch dualnav serial gps) The radiio is from 2004 and might have a problem with the GN prefix so tips on how to rewrite to GP rmc or only rmc would be fine.

Eveen if I disconnec the serial plug to the radio, the message is corrupted so it seems that the error is a internal opencpn error.

[bdbcat]

Petter...

First guess is that no-one is listening for TCP connection on port 10.8.1.10:50001. So the TCP/IP transmitter in OCPN reports error, no connection.

Who is port 50001, anyway?

Dave

[petter5]

port 50001 is serial port two on the 4 port rj45 to serial server. The ports has address 10.8.1.10:50000 10.8.1.10:50001 10.8.1.10:50002 and 10.8.1.10:50003

Port 50000 is in connected to the gps and works correct, port 50003 is connected to AIS and works correct, trying to get the output to the DSC VHF, no success.

The VHF is rs232 4800 baud and the DSC position function works fine when connecting a rs232 gps directly. I'm trying to get opencpn to provide RMC feed for the DSC over port2 (50001) function to avoid having two GPS units.

The serial server serial port two (50001) is configured RS232 4800 baud.

Originally Posted by bdbcat

Petter...

First guess is that no-one is listening for TCP connection on port 10.8.1.10:50001. So the TCP/IP transmitter in OCPN reports error, no connection.

Who is port 50001, anyway?

Dave

[bdbcat]

Petter5...

I see.

Your config is not too unusual in any respect. OCPN does this function just fine for me every day. It is how I feed my mobile devices onboard.

The issue the OCPN is reporting by the red line in the NMEA debug screen is that there is no valid TCP/IP connection to port 50001. Nobody is answering the phone. The content of the message is not relevant to the error report. Maybe Port 2 is not set up for input from the PC ?

Anyway, to diagnose this, get and install Wireshark, a PC based TCP/IP sniffer. This will show you all the traffic in and out of your PC.

Dave

[petter5]

I got away with the "red" debug window message - it was a broken wire in the connector. Still I have a small problem. Using a Digital yatch dualnav GPS in full "turbo" mode at 115200 baud with Glonass +GPS satellites, it seems that I get GNRMC sentences but no GPRMC. To feed position data to the 2004 model DSV VHF radio, it seems that this radio require GPRMC and does not understand GLRMC. I'm trying to understand if it is possible to get the "output as nmea repeater" to rewrite GNRMC to GPRMC so the old VHF will display position.

[bdbcat]

Petter5...

Modifying the transmit TALKER name on-the-fly is not supported by the OCPN NMEA multiplexer.

Sorry
Dave

[smac999]

Why are you feeding into the pc and and back out to vhf? Then the pc must be on, and more things to fail .just tap into the serial gps feed before the multiplexer and feed direct from gps to vhf.

Are you sure you want rmc? Not really used any more. Gll and gga is more common