No wind speed on dashboard

[AEM]

hi, I have multiplexer vYacht connected to Raymarine SeaTalk net, with ST-60 wind instruments. The OpenCPN Dashboard shows all data, except Wind Speed.
The NMEA protocol show:
<GREEN>21:01:07 (TCP:192.168.1.1:2947) $GPVWR,101.00,L,,,,,,*16<0x0D><0x0A>
<GREEN>21:01:07 (TCP:192.168.1.1:2947) $GPMWV,259.00,R,,,A*74<0x0D><0x0A>
<GREEN>21:01:07 (TCP:192.168.1.1:2947) $GPVWR,,,1.40,N,0.72,M,2.59,K*1C<0x0D><0x0A>
<GREEN>21:01:07 (TCP:192.168.1.1:2947) $GPMWV,,R,1.40,N,A*31<0x0D><0x0A>

The Wind Angle is working well, but no data of Wind Speed.
I tested this NMEA sentence in multiplexer vYacht built-in window of K-signal and all worked well - Wind Angle and Wind Speed.

Please comment, thank you.

[Hakan]

GPVWR,101.00,L,,,,,,* >> Only angle but no speed. (Third position)
GPMWV,259.00,R,,,A* >> Only angle but no speed. (Also third position)
GPVWR,,,1.40,N,0.72,M,2.59,K* >> No angle but speed 1.4 knots.
GPMWV,,R,1.40,N,A* >> No angle but speed 1.4 knots.

For the VWR:
The problem here is we, Dashboard, first check if there's a valid wind angle. If so the angle and speed are shown in the instruments. With no valid angle nothing is shown. So, the sentence with wind speed only is not parsed since no angle is present. The logic here would be: if no angle the speed is useless. No one expected any instrument should split angle and speed in two messages. But this may be a result of the N2k to NMEA0183 conversion.

Now the MWV sentence is not handled in the same way. But the VWR is prioritized over MWV so since the VWR with the angle is accepted and given priority MWV is omitted.

What you could test is to filter out the VWR sentence in connections so the MWV is used.
For the TCP connection where you receive these add a Input filter to "Ignore sentences" -> click the 3-dotted button and add GPVWR. See my shot.

[Hakan]

AEM..
Hmm.. My advice may not be the best. The angle and speed will be displayed but fluctuating.
Conclusion:
Dashboard is not fully prepared for N2k > NMEA0183 conversion. The N2k handle each value as a single tag and not a combined sentence for e.g. wind conditions. So the angle is first converted to a "half" VWR and a MWV. Then when wind speed is received it's also converted to a "half" VWR and MWV.

It may be we would adapt Dashboard for this since the use of N2k > NMEA0183 converters would increase? Or is the above behavior due to a "bad" converter?

[AEM]

Thank you, the Wind Angle and Wind Speed are shown now on Dashboards, with filter GPVWR, but the wind arrow and number is flashing every half second. How to improve this ?

[Hakan]

AEM..
Will need a code change in OCPN. Let's see if this can be handled in the ongoing beta test for O v. 5.6
Any other views?
Håkan

[Hakan]

Thoughts:
I would have expected the N2k to NMEA0183 converter to gather angle and speed data into one NMEA0183 sentence (VWR/VWT/MWV) before transmit.

Does anyone know if other converters does that and this example is an isolated gadget with a dismal logic?

[hoolie]

The Shipmodul MiniPlex-3 uses a single PGN 130306 Wind Data to convert to 0183 MWV and/or MWD.

The Vesper Marine XB-8000 does the same, using the same PGN.

I have Raymarine wind instrument data through NMEA 2000 to Ocpn and have never had the problems described by the OP.

[Hakan]

hoolie..
Very good. Many thanks for that info.
Can we than conclude that either is AEM's converter not using correct PGN or don't find it. In the latter case it's the wind instrument that's using not suitable PGP?
If so we would not try to "correct" a badly formatted NMEA0183 sentence in OCPN/Dashboard. Possible creating other problem.

AEM.. Thoughts?

[hoolie]

Re-reading AEM's original post it's not clear whether he is using N2K at all. He refers to SeaTalk from ST60s into a vYacht multiplexer that converts to NMEA0183. That device has a reputation for being pretty basic so may cut some corners?

[Hakan]

hoolie..
Yes, good point. SeaTalk has many shapes so I may have misunderstood.

[hoolie]

SeaTalk1 sends windspeed and wind angle in two separate datagrams. Evidently the vYacht multiplexer doesn't combine them into a single NMEA0183 sentence as it should ...

[AEM]

yes, the vYacht is connected to ST-60 (SeaTAlk1), output is 0183 to wifi/ethernet.
So, I have woking Wind data now, but fluctuating, it is better the before, but no reason now to change the vYacht multiplexer.