Problem installing Openplotter on a Raspberry Pi

[cpedw]

I had an issue where there was no nmea0183 data arriving in ocpn from signalk. This turned out to be a line in "settings.json" in ".signalk" folder.

The line was "suppressnmea0183:true" I changed it to false & all good.

"telnet 10110" will show the flow (need to install telnet if using OP2)

Might help someone.

I checked the settings file but it doesn't have that line. telnet didn't show anything.

Another option you might try - get rid of all the serial app entries and set up the GPS in SignalK using /dev/ttyUSB0 4800

Serial app — OpenPlotter 2 documentation

No, I didn't succeed with that approach either.

So, given that this was a Lockdown Project to get familiar with OpenCPN but not how I plan to use it, I'm going to move on.
I plan to use an AIS to supply GPS data and AIS info via NMEA so it will need to use the UART not USB I think but I can't move on until I'm let out again.

 

[GHA]

I checked the settings file but it doesn't have that line. telnet didn't show anything.


No, I didn't succeed with that approach either.

So, given that this was a Lockdown Project to get familiar with OpenCPN but not how I plan to use it, I'm going to move on.
I plan to use an AIS to supply GPS data and AIS info via NMEA so it will need to use the UART not USB I think but I can't move on until I'm let out again.

Something weird going on with your GPS and the Pi, openplotter works out of the box - the openplotter forum might well know what and if it6is some wired bug then the developers would be very keen to hear about it.

Uart - remember the Pi pins are 3.3v,connect nmea to that very good chance you'll blow the pins. Most people probably use a cheap rs23w/USB converter off ebay.https://www.raspberrypi.org/documentation/configuration/uart.md

The sgsim is a quick way to see it all in action, without doubt the openplotter /signalk image is the best game in town for the Pi.

 

[cpedw]

Well just to prove how unreliable I am, I'm here to report that it's now working.

I googled to check what I was talking about, prior to complaining to the openplotter forum. I came across a 2017 thread that talked about Kplex so I gave that a go. It complained that a plugin needed installing so I did. Then I tried to connect again and it said "Coming soon"! So I went back to SignalK and the gps started to show up (first in the NMEA debug window - it didn't have a fix for a time). I've no idea if there was a connection with the kplex plugin but I'm not going to remove it just yet.

I think I may be getting too old for such a protracted debugging operation.

 

[GHA]

Well just to prove how unreliable I am, I'm here to report that it's now working.

I googled to check what I was talking about, prior to complaining to the openplotter forum. I came across a 2017 thread that talked about Kplex so I gave that a go. It complained that a plugin needed installing so I did. Then I tried to connect again and it said "Coming soon"! So I went back to SignalK and the gps started to show up (first in the NMEA debug window - it didn't have a fix for a time). I've no idea if there was a connection with the kplex plugin but I'm not going to remove it just yet.

I think I may be getting too old for such a protracted debugging operation.

Can you remember the name of the plugin? I'll post something on the openplotter forum so maybe they can include a fix in a future release. Opensource can work really well with stuff like that

 

[laika]

I googled to check what I was talking about, prior to complaining to the openplotter forum. I came across a 2017 thread that talked about Kplex so I gave that a go. It complained that a plugin needed installing so I did. Then I tried to connect again and it said "Coming soon"! So I went back to SignalK and the gps started to show up (first in the NMEA debug window - it didn't have a fix for a time). I've no idea if there was a connection with the kplex plugin but I'm not going to remove it just yet.

Did someone say "kplex"? For reference, I know quite a lot about kplex but know little about openplotter because last time I looked the only way to download it was with kim dotcom's dodgy software. There are no kplex plugins or "Coming soon!" messages so you must be seeing something non-kplexy from openplotter. The kplex google group is generally the best place to answer kplex questions but also happy to address anything here.

 

[cpedw]

it is listed in openplotter settings 2.2.3 under openplotter apps as Kplex 2.0.0-dev.

The "Coming soon" message comes if I try to connect the gps in Serial 2.1.0 by "Add to Kplex". I have no idea what Kplex does. When I feel daring, I will try uninstalling Kplex to check if that's what made the gps connect. I don't think it did but that's not really based on knowing what's going on!

 

[laika]

I have no idea what Kplex does.

It's an NMEA0183 multiplexer: takes NMEA-0183 from a variety of sources, does things like filtering, rate limiting and prioritisation, and spits the data out in configurable ways. It used to be the central hub of openplotter feeding the various other programs but a quick look at the openplotter docs on openplotter.readthedocs.io show things may have changed in the latest release. kplex is driven by a text config file (/etc/kplex.conf). The openplotter team wrote the graphical interface which makes configuration easier but doesn't allow you to do any of the more interesting stuff.
https://sailoog.gitbooks.io/openplotter-documentation/en/nmea-0183.html
http://www.stripydog.com/kplex/overview.html


Disclaimer: said before but I'll say it again...I've never installed openplotter and I'm not currently near any hardware to do it.

A problem here is that only one process can "own" the gps and there are multiple ways to connect everything together. OpenCPN, the SignalK server, kplex and gpsd can all read a serial GPS device and share the output with other programs. If you were running gpsd as you seemed to be earlier, that would own the gps device. You wouldn't be able to connect other programs directly to the gps's serial device, you'd need to talk to gpsd over a network connection to get the data. I had a discussion with sailoog about 5 years ago on how to configure kplex to ask gpsd for data and he was going to add a facility to do that in "the next release" but don't know if it happened (but it can certainly be manually configured). OpenCPN can set up a connection to talk to gpsd. Don't know about the signal K server.

Bottom line...openplotter is an integrated suite of programs. Following configuration guides for any individual component may lead you astray. You almost certainly don't want to connect OpenCPN directly to the GPS, you'll want to connect OpenCPN to whatever program openplotter thinks should "own" the GPS.

As mentioned it *used* to be the case that kplex would be in the middle of openplotter feeding all the other programs. Later the signalK server became more central with kplex still owning most of the nmea0183 side but the latest documentation seems to be a shift to having the signalk server firmly in the middle. That may be a source of confusion if you're starting by reading the current docs then troubleshooting using old discussion threads or the older and more complete documentation on gitbooks.io.

Apologies that I can't help directly with openplotter (hmm..perhaps I should mail order *another* pi...). My top tip is work out what the architecture should look like...this is from older docs:
https://sailoog.gitbooks.io/openplotter-documentation/en/how_does_it_work.html
and this from newer:
https://openplotter.readthedocs.io/en/latest/description/how_does_it_work.html
Note that kplex, labelled "NMEA Multiplexer" in the first diagram, does not appear in the second.

The forum GHA pointed at earlier is helpful.

Also note that often non-"marine" GPS units default to 9600 baud and sometimes a non-nmea output format and have to be configured to speak nmea-0183.

I can go on at length about why kplex does nmea-0183 multiplexing way better than the SignalK server, but most users probably don't care and you undoubtedly want to go with whatever the default is.

 

[GHA]

Well just to prove how unreliable I am, I'm here to report that it's now working.

I googled to check what I was talking about, prior to complaining to the openplotter forum. I came across a 2017 thread that talked about Kplex so I gave that a go. It complained that a plugin needed installing so I did. Then I tried to connect again and it said "Coming soon"! So I went back to SignalK and the gps started to show up (first in the NMEA debug window - it didn't have a fix for a time). I've no idea if there was a connection with the kplex plugin but I'm not going to remove it just yet.

I think I may be getting too old for such a protracted debugging operation.

'prior to complaining to the openplotter forum.' --- it's not really complaining though, it's helping. If users don't tell the developers of strange behavior or bugs then they can't fix them.

Hard to tell but it sounds like something strange was going on between your GPS & the raspberry pi. A quick google came up with some reviews on amazon from 2020 so in tech terms it's pretty ancient and the reviews mentioned setup and driver problems so it could well be the culprit.

Is it working connected to signalk now?

 

[GHA]

Did someone say "kplex"? For reference, I know quite a lot about kplex but know little about openplotter because last time I looked the only way to download it was with kim dotcom's dodgy software. There are no kplex plugins or "Coming soon!" messages so you must be seeing something non-kplexy from openplotter. The kplex google group is generally the best place to answer kplex questions but also happy to address anything here.

"I know quite a lot about kplex".. so modest You would do having written it
OP2 has a dedicated app for setting up kplex now with some autosetup bits missing hence the 'coming soon' message, though most people probably use signalk to do the multiplexing these days.
Openpllotter downloads from this site these days - nx8035.your-storageshare.de/s/Yapesa2XPJptgaz

 

[cpedw]

'prior to complaining to the openplotter forum.'

Is it working connected to signalk now?

Yes, "complain" was not the mot just.

Yes, it seems to be spot on. I should experiment with uninstalling Kplex but I'm inclined to leave well alone (also quite lazy!).

 

[GHA]

for anyone else interested - here's a demo of one of the dashboard apps available in signalk - best one imho.
KIP
press load demo to view
fully configurable.

 

[NickRobinson]

Struggling to get Opencpn or Pypilot installed correctly.
Images load up on a new Pi Zero but throw error messages and will not open Openplotter though the Pi desktop functions.
Sean's standalone pypilot/tinypilot freezes half way through the initialisation.
Do I need a crustier pi?

 

[jwfrary]

Struggling to get Opencpn or Pypilot installed correctly.
Images load up on a new Pi Zero but throw error messages and will not open Openplotter though the Pi desktop functions.
Sean's standalone pypilot/tinypilot freezes half way through the initialisation.
Do I need a crustier pi?

Not tried it on a zero, but the documentation recommends 3 or a 4.

I'm running on a pi 4 2GB and the ram situation is overstated. I expect if your using raster charts then you need a 4GB but my vectors run fine. Im using open cpn and signal k to collect data from the network and plot it with influx and graphana.

PS i tried my image on a pi 2 i had laying around and it doesn't boot.