OpenCPN - NMEA Data from TCP Input

[framen]

Hello everyone,
first of all sorry for my english.
I am new to OpenCPN.
I am trying to receive nmea data from an internet server, but I am not able to configure it. I already tried tcp2rs, but when i configure opencpn to listen to com1 where data was redirected it says "Could not open serial port COM1.

Any idea.
Tnx

[cmilla]

In windows, try with GPSGate from www.franson.com.

You can to make a bridge from IP to one o more virtual COM ports in your PC.

I Use OpenCPN on board across my WIFI, and anywhere by Internet.

I have connected both RS232 ports from AIS and NMA to a double Serial/IP converter (Moxa Device Servers NPort® 5210 - 2-port RS-232 serial device servers) and this adapter to my router, then I can to access data fron LAN, WIFI and Internet with OpenCPN.

Best regards, Carmelo Milla
www.olaje.com

[night0wl]

Any opensource solutions to this challenge?

[bdbcat]

nightOwl...

This feature is scheduled for inclusion in the next full Release of OpenCPN, Version 3.2, due later this fall.

Thanks
Dave

[Paul Elliott]

Originally Posted by night0wl

Any opensource solutions to this challenge?

NavMonPc will bridge / route NMEA data between TCP/IP and RS232 ports (virtual and physical RS232 ports). It's not open source, and it is a Windows-only program, but it is free.

[MAS3]

VSPE will do this too in Windows 32 bit, for free.
Windows 64 bits will cost you money, because fees have to be paid to microsoft to prove that the software is safe (right..).
You can find out more through Eterlogic's website.

[jram]

Any linux offerings that will do this? I was hoping to use my Raspberry Pi as a navigation information bridge.

[rolker]

Originally Posted by jram

Any linux offerings that will do this? I was hoping to use my Raspberry Pi as a navigation information bridge.

The socat utility should be able to do that.

Interestingly enough, I also just happen to fix some code in my branch that allows AIS data to be read from a TCP/IP connection. I'm still getting used to GitHub, but I also noticed what seems to be other efforts to revamp the data streams which might make the use of external utilities unnecessary?

[bdbcat]

Hey guys....

If you really need this right now, and feel like hacking, have a look at ais.cpp, line 3190. We already have an undocumented way to get AIS data from TCP/IP. You could do the same for GPS data, if you want to play....

   /*
     A special test for a user defined FIFO
     To use this method, do the following:
     a.  Create a fifo            $mkfifo /tmp/aisfifo
     b.  netcat into the fifo     $nc {ip} {port} > /tmp/aisfifo
     sample {ip} {port} could be  nc 82.182.117.xx 6401 > /tmp/aisfifo
     c.  hand edit opencpn.conf and make AIS data source like this:
     [Settings/AISPort]
     Port=Serial:/tmp/aisfifo

     This also works if you have an ascii ais log
     for which you can simply $cat ais.log > /tmp/aisfifo
     */
    if(m_pPortName->Contains(_T("fifo")))
    goto port_ready;

This interface is unsupported, and will go away in the next Release.

Have Fun
Dave

[rolker]

Dave, I updated the existing socket code and committed it to my master branch on github.

https://github.com/rolker/OpenCPN

Is that code going to disappear as well in the next release? If so, will it be replaced with something that will allow me to connect to a TCP server to receive AIS messages?

My use for this functionality is for monitoring the transmission of area notices via AIS regarding Right Whale detection off of Boston.

Right Whale Listening Network, Cornell, Bioacousti

To monitor this from my office, I have access to the Coast Guard's National AIS data feed so I made a few updates to the socket code in ais.cpp so I can skip the suggested step of setting up a virtual serial port.

The updates include:
- Make a TCP source show up in the config gui (TCP/IP:server shows up instead of None)
- Allow port to be specified and defaults to previously hard coded one if omitted. (ex TCP:IP:aisserver:12345)
- Since the data stream I get includes extra meta data, the NMEA part (From '!' to the checksum) gets extracted and anything else is discarded, which should make this flexible enough to use with other sources which might include timestamps and such.

The data stream I use includes live data from all US waters, so it's a good stress test for OpenCPN's AIS functionality!

It would be nice if future versions would support the functionality I mention above and I'm willing to lend a hand in the coding to make that happen.

Roland

[bdbcat]

Roland...

The implementation will change for the next release, but the functionality will remain. If you have something that works now, I would not recommend investing too much more effort in making it production worthy. It will all change shortly.

You will still need to hack the code to filter out the specific message you want. This sounds like a good place for a PlugIn.....

Glad you got it to work for your specific case with the existing code, though.

Dave

[rolker]

Dave,

I got it to work, almost. It runs for a while and then the AIS data stops updating. I haven't debugged the reason, and don't feel like doing so it is all going to change anyway.

I noticed Pavel's datastream branch on GitHub. I assume this will be the new code to replace this functionality correct? I just fetched it and am looking at it now. I'll see if I can lend a hand in testing it.

Roland