Full Version: Issue converting GPS from Signal K to NMEA0183
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Hi everybody,

I am back with another question!  Big Grin

So far I have been able to use different components (such as BNO055 IMU) on an Arduino then on OpenPlotter. It works like a charm and to give you the different steps, here is how it works:

- Get raw data on the Arduino Mega from sensors
- Data is sent with Signal K format from the Arduino to Raspberry Pi (USB)
- A short Python program get the Serial data and transfer it to Signal K server
- On OpenPlotter, I get this data (via Signal K diagnostic) and I convert it to NMEA0183 thanks to the NMEA0183 Converter
- I then get this data on OpenCPN or QtVlm or Instumental Panel of Signal K server

Issue is when it comes to GPS signal. I cannot get the Signal K sentences to be read by the NMEA0183 Converter when the data sent is not a number. Is it normal?

To give you an example, to write NMEA sentences such as $...RMC or $...GCA , you have to indicate "N" (North) or "S" (South) when it comes to the GPS direction. But if I write letters "N" or "S" in my Signal K sentences, it is not recognized by the NMEA0183 Converter and it does not see it in the available Signal K data...

I tried "-1" and "1" instead but it does not work either..

It can seem silly to use the Arduino to convert NMEA0183 to Signal K and then OpenPlotter to the opposite but the idea is to use the Arduino as a hub to centralize all data from sensors. 

Plus, unless I am missing something, by connecting the GPS directly to the Raspberry, I loose the benefit of having GPS data on the Signal K server...

Thank you for your help!

[quote pid='4592' dateline='1520240179']
hello, lucas.
I am a beginner and I couldn't help you.
But I want to retrieve the information on the signal k server.
I'm trying to display them on a 20x4 LCD.
what is the code to recover them, I can not ... Also I don't have access to the K Diagnostic signal on OP desktop...