[SOLVED] Latitude conversion, N2K to NMEA0183

[MatsA]

Wow !

What a software package !!

I have used SignalK for a while but just stumbled over this impressing project. Really cool packetizing !!!! 

Some hours later I have figured out some….. so now I am up and running OpenPlotter 0.11.9 alpha on RPi3 with a Actisense NGT-1 connected to my boats NMEA2000 network.
Then I have configured the NMEA 0183 generator creating some sentences, but the conversion of latitude seems wrong ?! Se picture

According to OpenCPN I’m in the middle of Africa ;-)     but actually staying in the south of Sweden ? 

Mats


  openplotter_1.pdf (Size: 58.25 KB / Downloads: 233)

[e-sailing]

At the moment you can't create the correct sentence GLL.
SignalK has convert longitude and latitude to degrees. But NMEA 0183 needs the format XXYY.ZZZZ => XX°YY'(0.ZZZZ*60)"
To get the NMEA 0183 format for longitude you have to generate the number from SignalK value (UU.UUUUUU) by int(UU.UUUU) *100+ int(UU.UUUU % 1) / 60 * 100.
The NMEA 0183 Generator isn't able to do this at the moment. It also isn't able to switch from south to north or east to west.
We should think about a converter which is able to convert SI (International System of units) to special NMEA format.

[MatsA]

At the moment you can't create the correct sentence GLL. .....

Thanks for a quick answer, really appriciate it.

Done some thinking ….

• I'm not a programmer but, if the NMEA converter, in some cases, refers to a conversion program instead of a formula then You could do whatever what was necessary ? 
  
• If the SignalK plugin https://github.com/SignalK/signalk-to-nmea0183 have handeled the GLL or the RMC sentence, should that solve the problem ? If so, what ”mechanism” should forward the data to OpenCPN ?
  
• Have ordered the USB SDR AIS receiver, and read the OpenPlotter(OP) documentation, and wonder how the AIS info is transfered to OpenCPN ? Docs just says, what I found, ”select Enable AIS reception”
  
• VDM, VDO sentences don’t seems to be supported by the NMEA 0183 generator ? or is there another way to send these sentences via TCP/UDP to for example an iPad with iSailor ? 
  

/Mats

[Sailoog]

As e-sailing said, we need still to work on NMEA 0183 generator to make it more flexible.

Yes, that signal k plugin should do the trick.

AIS sentences from AIS SDR are transferred to OpenCPN out of the box just enabling AIS reception. They are sent to localhost UDP 10110, then they are multiplexed by kplex and sent to the input localhost TCP 10109 configured on OpenCPN. To send NMEA remotely make your device listen also to TCP openplotter:10109.

[Sderbyshire]

Hi Mats

Interesting thread, as i plan to integrate opencpn with the n2k network on my yacht later in the summer.

I bought Amita in Saltsjobaden in 2012, but she's in the med now where its warmer!

Steve

[MatsA]

As e-sailing said, we need still to work on NMEA 0183 generator.......

Thanks for a distinct answer !

* OK

* Checked on my standalone SignalK installation and the output for the plugin is TCP and port 10110 so won't there be a conflict ? ... so send it out to another port and then put a listener to Kplex which multiplex the sentence along with the other info on TCP 10109 ? 

* OK nice solution. Checked it with a DPT sentence, created with the NMEA0183 converter, received by my iPad and it worked like a charm !!

I found the enclosed picture from an interview with You, and it really explains a lot. Maybe it should be in the documentation ? ( Despite there is a wrong port number on the output from Kplex     )

If You want some help with documentation I could add some regarding Actisense NGT-1 ? 

And thanks for a fantastic job/application !!

Mats

---

Hi Mats

Interesting thread, as i plan to integrate opencpn with the n2k .....

Hi !

Stockholm archipelago is very nice, did You check it out ? 

Our boat is from 2006 so I mix older things with N2K, according to enclosed pictures. 

Don't hesitate to adress me if You have some questions !

/Mats

[Sailoog]

- No conflict with TCP 10110, we do not use it. Be careful with infinite loops. You do not need to send the NMEA to opencpn from the signal k to NMEA plugin because those sentences have already be sent to opencpn by kplex.

- Yes thanks, I forgot that picture. It needs to be updated and I will add it to docs.

- All help is welcomed. Actisense NGT-1 is compatible with openplotter but we prefer our CAN-USB stick, more features and designed specially for openplotter

Thanks for tour support

[MatsA]

- No conflict with TCP 10110, we do not use it. Be careful with infinite loops. You.......

Thanks for Your picture update, nice !

Didn't really understand the registration procedure for helping with documentation, does that disqualify me ?  , but my GitHub name is MatsA.  

The Actisensense is so expensive compared with Your solution so I don't think it really counts, but just to show that Your solution is very flexible.

/Mats

[Sderbyshire]

- All help is welcomed. Actisense NGT-1 is compatible with openplotter but we prefer our CAN-USB stick, more features and designed specially for openplotter

Thanks for tour support

Hi, i'd like to trynthe can-usb stick when i'm next out on Amita at the start of July.

Are they available in the shop ( last time i tried they weren't )

Steve

[SkipperEarly]

@ MatsA : yes please share some descriptions for connecting the actisense ngt-1 - we could all benefit from this.

@ Sailoog: sorry but have missed that your CAN-USB stick is now available. From my point of view its not in competition to the actisense but an alternative for more price conscious users who don't mind to customize their connectors. I was not aware that there is also a feature difference, could you please share some details? - thanks.