Open CPN 433->node-red->nmea 0183 generator not working... am I doing something wrong

[ensaymist]

Hello Folks


Been playing about with a weather station for a poor mans to use as a poor mans wind instrument (to save looking up )


Great news is that it talks over rtl_433 and have it cherping away and implemented into OP internal node-red... can see the values changing in debug window, and represented on the signalk instruments.


Tried to use the NMEA 0183 generator to push out the VWT string, it grabbed the first values when initially added but doesn't update on change of direction or wind speed.


Am I doing something wrong ?


Thanks


Craig B

[Harry99]

Hi Craig,
I have the same idea to use a wether device as a poor man's sailing device. Can you tell us which device you are using?
How did you manage to get the data to signal k?
Maybe your problem is, that the 433mhz device only sends data every minute or so. So there is no data between these sendings.
Would be great to hear from you soon.
Greetings Harald

[ensaymist]

Hi Harald


It's the £60 Bresser 5-1 weather center.


It polls every 10 seconds... and easily captured with RTL_433... this is then pushed over MTQQ to node-red, then manipulated a little bit and dropped onto signalk.

Just struggling to get the OpenCPN bit working now.

I am thinking of spoofing the nmea string pushing it via UDP onto 10110 (kplex ??)

[ensaymist]

Originally Posted by ensaymist

It polls every 10 seconds...

{"time" : "2020-02-17 17:11:42", "model" : "Bresser-5in1", "id" : 216, "temperature_C" : 18.800, "humidity" : 50, "wind_max_m_s" : 2.800, "wind_avg_m_s" : 1.600, "wind_dir_deg" : 247.500, "rain_mm" : 12.000, "mic" : "CHECKSUM"}

[ensaymist]

finally getting somewhere....

had to convert the direction into radians... now one of the pins on sailgauge is working, from the data received from the weather station.

off to the boat this afternoon to plug into gps and see if we get the rest of it working (and the dashboard on OpenCPN)

[Harry99]

Great news! Can you tell us, how you did the job?

Congratulations, Harald

[ensaymist]

Here it is up and running on opencpn (openplotter) on a pi. Write up to follow after tea

[ensaymist]

Some quick notes for replicating...


Equipment;
* raspberry pi 3, berrygps-imu hat, mounted in a spartipi case with 7" touchscreen- openplotter v1.2 (on raspian stretch)
* nooelec sdr usb fob with aerial
* Bresser 5-1 weather center


Software;

https://github.com/merbanan/rtl_433, compiled and installed
https://github.com/mverleun/RTL433-to-mqtt, compiled and installed
signalk -
* signalk-node-red, installed and enabled
* signalk-mqtt-gw, installed and enabled
* signalk-to-nmea0183, installed and enabled




Instructions;
ensure that signalk mtqq local server is running


configure RTL433-to-mqtt to connect to mtqq server and run '/usr/local/bin/rtl_433 -f 868300000 -Y classic -s 250k -F json', execute and background process


configure signalk-node-red (nodered-flow attached), please note the wind-dir has logic added to show negative values for angles above 180, then is converted into radians... then presented as number... then the topic changed to match the appropriate environment.wind token.


once that is deployed you should be able to see the values populated in node-red (and displayed in debug screen), systemk instrument panel should also be showing values.


systemk diagnostics should be showing every 10 seconds.



configure signalk-to-nmea0183 to send the appropriate wind strings (or enable all of them ), submit and restart signalk.


now in opencpn ensure has connections to TCP localhost 10110 and 30330, nmea debug should now be showing all the nmea lines coming in.


add the apparent wind speed and angle to the dashboard, it should populate shortly with the data fed through signalk from the weather station.


signalk sailgauge is also worth a look.



enjoy !

[Harry99]

Wow, thanks a lot for all the information.
Great work!

Yours Harald

[rgleason]

For all you node-red Victron users.
Venus OS with node red
https://github.com/victronenergy/venus/issues/378