Signal K and Autopilot

[Svinninge]

Hi all
I have a Raspberry Pi running a Signal K server.
My Autopilot is connected to the Raspberry using NMEA 0183 RS232
OpenCPN is running on a laptop using Ethernet port 3000 connected to Raspberry with the Signal K server.
Data from Signal K to OpenCPN works good.

But is it possible to create a route in OpenCPN and send Autopilot data over the Signal K connection to RPI?

So my question is, is the Signal K connection one way or both way?

Best
Per

[SCarns]

Originally Posted by Svinninge

Hi all
I have a Raspberry Pi running a Signal K server.
My Autopilot is connected to the Raspberry using NMEA 0183 RS232
OpenCPN is running on a laptop using Ethernet port 3000 connected to Raspberry with the Signal K server.
Data from Signal K to OpenCPN works good.

But is it possible to create a route in OpenCPN and send Autopilot data over the Signal K connection to RPI?

So my question is, is the Signal K connection one way or both way?

Best
Per

Answer: Both, but it depends.

Yes, SignalK can control an autopilot. There is a SK plugin specifically for it. Also, OpenCPN can send a route easy enough. I do it all the time, but have an issue with doing it through SignalK. Hence the "it depends" part. It will come down to your connection and how it's set up. SignalK documentation is a bit spotty, but I've been using it for a few weeks now and find it to be easy to figure out and solid. Looking for a RPI myself to do host SignalK, just like you're doing.

OpenCPN and it's SignalK connection, I believe, are currently "read only." That will most likely change in the future. So for now, you'll need to have an output from OpenCPN through the NMEA-SignalK converter (port 10110) or directly connect and configure the NMEA 0183 RS232 connector direct to the laptop for OpenCPN control.

Regardless, yes, it can all work in theory, but you'll need to spend some time making sure it's setup properly and test it.

[seandepagnier]

opencpn only receives signalk, it does not output signalk.


pypilot only sends and receives signalk since version 0.21. control from signalk is not well tested.



signalk definitions for autopilots are currently not very well thought out. They are based on proprietary nmea2k autopilots which is a shame. see this discussion:
https://forum.openmarine.net/showthread.php?tid=2858

[LennartG]

Svinninge,
for the autopilot, take a look at the Twocan plugin. It has, in this respect, the same functionality as Signal K. Could be an alternative.

/Lennart

[verkerkbr]

Originally Posted by Svinninge

Hi all
I have a Raspberry Pi running a Signal K server.
My Autopilot is connected to the Raspberry using NMEA 0183 RS232
OpenCPN is running on a laptop using Ethernet port 3000 connected to Raspberry with the Signal K server.
Data from Signal K to OpenCPN works good.

But is it possible to create a route in OpenCPN and send Autopilot data over the Signal K connection to RPI?

So my question is, is the Signal K connection one way or both way?

Best
Per

Yes, it is possible to send route information from OpenCPN to the SignalK server.

Make an extra connection In OpenCPN outgoing (not out en in). At the two dots line below remove all settings. And tick only the ones your need.

Setting UDP localhost and port 2000

In SignalK add a new connection give it a name openc-in or something then:

NMEA183 UDP port 2000 and of course restart.

Now the route or waypoint data is coming form OpenCPN to the SignalK server.


Bram

[stevead]

Originally Posted by LennartG

Svinninge,
for the autopilot, take a look at the Twocan plugin. It has, in this respect, the same functionality as Signal K. Could be an alternative.

/Lennart

Not entirely correct. At the moment TwoCan does not control autopilots, nor does it convert NMEA 183 autopilot related sentences (APB, XTE etc) to their NMEA 2000 equivalents.

But this is moot as the OP wishes to connect a NMEA 0183 based autopilot. Peronally I don't understand why you just don't keep things simple and connect the autopilot directly to OpenCPN ?

[LennartG]

Svinninge and Stevead,
probably a slight misunderstanding here.

Neither Twocan nor Signal K generates NMEA 2000 sentences to control the autopilot from OpenCPN NMEA 0183.
Both Twocan and Signal K converts the required NMEA 2000 signals sent by the autopilot to NMEA 0183 (probably you only need/get HDG from the autopilot).
I am using this setup with Twocan myself having NMEA 2000 -> NMEA 0183 (only HDG is sent). The autopilot (Garmin GHP20) has an RS422 input for the required steering signals (RMC, RMB, APB etc.) that are sent by OpenCPN through a. FDTI USB to RS422 converter.
Works like a charm.
/Lennart

[Svinninge]

Originally Posted by verkerkbr

Yes, it is possible to send route information from OpenCPN to the SignalK server.

Make an extra connection In OpenCPN outgoing (not out en in). At the two dots line below remove all settings. And tick only the ones your need.

Setting UDP localhost and port 2000

In SignalK add a new connection give it a name openc-in or something then:

NMEA183 UDP port 2000 and of course restart.

Now the route or waypoint data is coming form OpenCPN to the SignalK server.


Bram

Thanks verkerkbr, i great idea!

I followed your recommendation and setup OpenCPN to send out using UDP port 2000. (I filtered RMC, no need for that)
Signal K now receives APB, RMB, XTE
In "SignalK to NMEA0183" plugin I checked APB,RMB,RMC,XTE
But my NMEA0183 RS232 Autopilot only receives RMC and XTE?

So APB and RMB is not sent from SignalK to the Autopilot, any idea?

Log:
Sep 06 18:17:45 2020-09-06T16:17:45.348Z signalk:streams:udp $GPAPB,A,A,0.3442,L,N,V,V,119.1343,T,003,60.5064,T ,60.5064,T*2C
Sep 06 18:17:45 2020-09-06T16:17:45.353Z signalk:streams:udp $GPXTE,A,A,0.344,L,N*5D
Sep 06 18:17:46 2020-09-06T16:17:46.082Z signalk:streams:serialport Writing:$GPRMC,161745,A,5926.8193,N,01817.6961,E,0 .3,0.0,060920,0.0,E*74
Sep 06 18:17:46 2020-09-06T16:17:46.082Z signalk:streams:serialport Writing:$GPRMC,161745,A,5926.8193,N,01817.6961,E,0 .3,0.0,060920,0.0,E*74
Sep 06 18:17:46 2020-09-06T16:17:46.352Z signalk:streams:udp $GPRMB,A,0.344,L,002,003,5927.018,N,01818.386,E,0. 403,60.488,0.144,V,A*50
Sep 06 18:17:46 2020-09-06T16:17:46.354Z signalk:streams:serialport Writing:$IIXTE,A,A,-637.088,R,N*78
Sep 06 18:17:46 2020-09-06T16:17:46.354Z signalk:streams:serialport Writing:$IIXTE,A,A,-637.088,R,N*78
Sep 06 18:17:46 2020-09-06T16:17:46.357Z signalk:streams:udp $GPAPB,A,A,0.3439,L,N,V,V,119.1343,T,003,60.4878,T ,60.4878,T*20
Sep 06 18:17:46 2020-09-06T16:17:46.362Z signalk:streams:udp $GPXTE,A,A,0.344,L,N*5D


SignalK settings.json:
{
"pipeElements": [
{
"type": "providers/simple",
"options": {
"logging": true,
"type": "NMEA0183",
"subOptions": {
"validateChecksum": true,
"type": "serial",
"baudrate": 19200,
"device": "/dev/serial/by-id/usb-FTDI_FT2232H_device_FT46QF1E-if00-port0",
"providerId": "AP0183-19200",
"toStdout": [
"nmea0183out"
],
"sentenceEvent": ""
},
"providerId": "AP0183-19200"
}
}
],
"id": "AP0183-19200",
"enabled": true
Best /Per

[Svinninge]

I think I found a solution, here is what I did:
- For the SignalK connection to UDP:2000 to OpenCPN, I put a name for the Sentence Event "nmeaOpenCPN"
- For the SignalK connection to my NMEA0183 autopilot, I changed the Output event to "nmeaOpenCPN,nmea0183out"
- In the plugin SignalK to NMEA0183 I only checked RMC.

The Autopilot now receives RMC, RMB, APB and XTE.

/Per

[rgleason]

Can you write this up more completely, so it can be added to Signal K wiki?

Originally Posted by Svinninge

I think I found a solution, here is what I did:
- For the SignalK connection to UDP:2000 to OpenCPN, I put a name for the Sentence Event "nmeaOpenCPN"
- For the SignalK connection to my NMEA0183 autopilot, I changed the Output event to "nmeaOpenCPN,nmea0183out"
- In the plugin SignalK to NMEA0183 I only checked RMC.

The Autopilot now receives RMC, RMB, APB and XTE.

/Per

[rgleason]

https://opencpn.org/wiki/dokuwiki/do...ftware:signalk

[SCarns]

In the end, my solution was to output APB, RMB, RMC and XTE from OpenCPN over TCP (on port 10110, the nmea0183 port) to a port in SK called OCPN which received 0183 into the "seatalkout" port, as used by the autopilot plugin in SK. All worked great for years. Sold the boat, but will do something similar on the next one.