New Plugin NmeaConvertor

[bdbcat]

Scud...


NmeaConverter v1.4.13 is now available in master catalog.


Thanks for the input

Dave

[Vesta]

Is it possible to send a converted NMEA message to a COM port using the NmeaConverter plugin ?

I have a NASA Clipper EasyLog display that reads an RMC sentence and uses the SOG data to display the boat speed. This is in knots and I'd like km/h so the SOG info has to multiplied by 1.852 and then sent to a COM port to go the EasyLog display.

gr. Leo

PS: If anyone knows of a possible hardware (RasPI) solution for this I'd appreciate the info !

[Antipole]

Originally Posted by Vesta

Is it possible to send a converted NMEA message to a COM port using the NmeaConverter plugin ?

I do not know the answer to your question but it should be possible using the forthcoming v2.2 of the JavaScript plugin - no release date yet.
If you are interested in trying it with the version in development, PM me.

[barcoMeCasa]

Originally Posted by Vesta

Is it possible to send a converted NMEA message to a COM port using the NmeaConverter plugin ?

I have a NASA Clipper EasyLog display that reads an RMC sentence and uses the SOG data to display the boat speed. This is in knots and I'd like km/h so the SOG info has to multiplied by 1.852 and then sent to a COM port to go the EasyLog display.

gr. Leo

PS: If anyone knows of a possible hardware (RasPI) solution for this I'd appreciate the info !

Should be possible using something like an arduino nano costing a few euros & drawing milliamps. Code would be simple, someone online could write it for you. Where does the rmc come from? Might need a few resisters to keep the nmea0183 voltage down to arduino levels.

[Vesta]

I have a spare Navilock NL-422MP GPS installed on the boat, it was intended for a hamradio APRS set-up, but I won't persue that line.

Aside from on the two on-board HP computers I have installed OpenCPN on a RasPi (complete package with the anchor symbol, forgot the name) so I'll try to add the NmeaConverter plug-in to that and see what is possible.

There's tons and tons of programming info on parsing available, guess this will evolve into a nice winter project

[barcoMeCasa]

Originally Posted by Vesta

I have installed OpenCPN on a RasPi (complete package with the anchor symbol, forgot the name) so I'll try to add the NmeaConverter plug-in to that and see what is possible.

Ah, sounds like you have openplotter installed, if so signalk can do that for you, is there an openplotter menu on the Pi if you click the raspberry symbol top left of the screen?

[Corsair63]

Originally Posted by Vesta

Is it possible to send a converted NMEA message to a COM port using the NmeaConverter plugin ?

I have a NASA Clipper EasyLog display that reads an RMC sentence and uses the SOG data to display the boat speed. This is in knots and I'd like km/h so the SOG info has to multiplied by 1.852 and then sent to a COM port to go the EasyLog display.

gr. Leo

PS: If anyone knows of a possible hardware (RasPI) solution for this I'd appreciate the info !

I do not see a big deal, but you'll have to try with.

RMC by default has the speed in knots.

so, you'll have to cheat in that sentence. and in the display you should have km/h with the display of knots.
1 - make a COM port connection with output feature and only transmitting EC sentences for the NASA display.
2 - with NmeaConverter plugin you must make a new sentence calling it:

$ECRMC, $GPRMC1,$GPRMC2,$GPRMC3,$GPRMC4,$GPRMC5,$GPRMC6,[$GPRMC7 here must be the conversion],$GPRMC8,$GPRMC9,$GPRMC10, ,

above is a close example, but you have to check the whole building of the sentence.

and follow instructions of NmeaConverter plugin making the calculation as per instructions.
I mean you must rebuild a new ECRMC sentence based in the GPS one but cheating in the speed filed doing your calculation and send km/h instead of knots, you'll have to consider that in display you'll receive km but still it will show the word knots.

GPS sentence | GPRMC
Following table mentions GPRMC sentence description with example.
➤Example of GPRMC GPS sentence:-
$GPRMC, 161229.487, A, 3723.2475, N, 12158.3416, W, 0.13, 309.62, 120598, , *10

Name or Field	Example	Description
Message ID	$GPRMC	RMC Protocol Header
UTC time	161229.487	hhmmss.sss
Status	A	A = data valid or V = data not valid
Latitude	3723.2475	ddmm.mmmm
N/S indicator	N	N = North or S = South
Longitude	12158.3416	dddmm.mmmm
E/W indicator	W	E = East or W = West
Speed over ground	0.13	knots
Course over ground	309.62	degrees
Date	120598	ddmmyy
Magnetic Variation		Degrees (E= East or W = West)
Mode	A	A = Autonomous, D = DGPS, E =DR
Checksum	*10	
<CR><LF>		End of message termination

[Vesta]

Indeed, the SOG data has to be converted (*1.852) to display the proper speed. I was curious if the NmeaConverter was able to create an output in order to reach the NASA Clipper EasyLog display before buying one.As for the 'knots' legend: I'll simply ignore that and concentrate on the humongous 40mm Clipper digits.

This will make a nice winter project, I will start with OpenCPN on a PC and then try the RaspberryPi