Checking NMEA out

[Jodel]

Hi,
I have used Openplotter to set up OpenCPN, Kplex etc. on a Raspberry Pi 3. I am testing it at home at the moment so it is not connected to any boat data sources.
However it is displaying a lat and lon, and when I select go to a way point I have range and bearing. Should it be outputting this data in NMEA format? When I open the NMEA debug window it is displaying no data. I have also set up a connection to Kplex and that also seems to be getting no data from OpenCPN.
Should OpenCPN be generating NMEA data and how can I check if it is doing so?
Jodel

[Dsanduril]

In the OpenCPN connection definition do you have the checkbox marked for "output on this port"? The default for new connections does not have this checked.

I just tested on my install, I don't even have a GPS connected, as soon as I made a "navigate to here" mark the debug window started receiving RMB, RMC, XTE, and APB sentences from O.

Also, sometimes the OpenCPN debug window doesn't start responding until you have closed the settings dialog box (by using 'OK').

[rooiedirk]

Jodel,
The only nmea data OpenCPN is generating is for an autopilot. And it does so only if you have an active route and at least one connection selected for output.
So it is completely normal if you don't see any data passing by.

[Jodel]

Hi Again,
I found the issue. I needed to close the Options/Connections with OK for the NMEA debug window to become active and start displaying data
Jodel

[katoema]

Hi, can I come in here. I use OpenCPN and have licensed UKHO charts running on it. As a delivery skipper I'm on different yachts and use an USB GPS puck.

Is there a way I can get a yacht's NMEA to OpenCPN, without having to have different setups for each yacht I'm on?

Martin

[nohal]

Originally Posted by katoema

Hi, can I come in here. I use OpenCPN and have licensed UKHO charts running on it. As a delivery skipper I'm on different yachts and use an USB GPS puck.

Is there a way I can get a yacht's NMEA to OpenCPN, without having to have different setups for each yacht I'm on?

Martin

Yes. There is absolutely no need for different config on each boat, you simply use the same port and connect to any of them. Given they all have NMEA0183 output of course.
If they don't you will need a conversion device from the particular bus available on the boat to NMEA0183 and that may, or not, mean you need different configuration.

[katoema]

I think I'm missing something here! What am I connecting to the Port? Is this assuming that the yacht is emitting something, and if so, what and how?

[nohal]

You talked about connecting to NMEA data produced by the boat you are delivering... To the “port” you usually connect some wires. But on other boats the data can be available over wi-fi. On yet another there may be no way to connect to it. And the last one may have no electronic instruments and produce no data at all. There is no universal answer.

[katoema]

That's what I thought. I've just done a 32 day delivery and the yacht had Raymarine "E" Series. According to Raymarine when I spoke to them I should have been able to make the connection through a Port, etc. It turns out, they admitted, that the manual supplied with that model was not updated with the correct IP address!

Making the connection through internal WiFi or Bluetooth should be possible, but the number of owners who did not know how their systems would do it, affords me to ask on the forum.

If it has to be wires, what is required to say make this a USB connection?

[nohal]

Originally Posted by katoema

That's what I thought. I've just done a 32 day delivery and the yacht had Raymarine "E" Series. According to Raymarine when I spoke to them I should have been able to make the connection through a Port, etc. It turns out, they admitted, that the manual supplied with that model was not updated with the correct IP address!

Making the connection through internal WiFi or Bluetooth should be possible, but the number of owners who did not know how their systems would do it, affords me to ask on the forum.

If it has to be wires, what is required to say make this a USB connection?

You are talking about an IP address, that means the unit probably has an ethernet port and you may connect to it over a network. Maybe wired, maybe wireless. It will differ boat from boat. But the IP of the plotter might be always the same. For the particular model. Maybe.

I suppose Raymarine E series also has an NMEA 0183 output that you can "make USB connection" by connecting the right pins to a serial-to-USB adapter compatible with your computer which you can buy on ebay for a few bucks or in a local computer store for a couple more. Of course any other plotter model will probably have to be wired differently and offer different possibilities.

As already said, there is no universal answer, and the subject may get quite complicated, but in your situation as delivery skipper, the part you yourself consider viable and doable for you, of the following should be in your bag:
- KNOWLEDGE, if possible extensive, of how the marine electronics work and the protocols and buses they use
- Manuals for the electronics that you know or expect to be on the boat you are going to deliver
- An ethernet cable ($2)
- serial-to-USB adapter (~$10)
- wires, clamps and tools to connect the above adapter to the proprietary connectors present on the hardware on boat (any amount of money)
- If you expect a NMEA 2000 network, a device to connect to the bus, like Actisense NGW-1 (~$150)
- If you expect SeaTalk and no Raymarine plotter, a device able to translate SeaTalk to NMEA-0183 (<$100)
- Your trusty USB GPS puck in case you will not be able or allowed to connect to the boat systems

[rooiedirk]

For delivery's I always use my own gps(puck) and a RTL-SDR for receiving AIS. That is really all you need for navigation. (Making a hard wired connection goes easily wrong with broken equipment as a result)

If the boat has more instruments available I just use the boats own instruments.

[Dsanduril]

For WiFi/IP you have the answers above. For traditional NMEA 0183 you need a USB to serial adapter that you can carry with you. Most times a USB-RS232 adapter will work, but the proper tool is a USB-RS422 adapter, something like this:

USB to RS422/RS485

I recommend something like the picture that includes a terminal block connector, it is far easier to connect to on strange boats. Of course, you'll still have to find a place in the boat's NMEA network to connect, and that may or may not be easy depending on the boat's wiring - and when you touch something you always run the risk of breaking it.

Once you have the adapter connected to your computer you can set up the connection in OpenCPN, then you shouldn't need to change it from boat to boat - one caveat, operating systems can sometimes change the virtual com port assigned to the USB adapter, most systems have a way to make the assignment static, but you may have to work at that.

[katoema]

Throughout the year I have between 8-10 deliveries, depending on passage times. Most are at short notice, but the longer ones are known well in advance. Manuals are out of the question, but the owner is always asked if I can get into their NMEA.

I use both OpenCPN and qtvlm (not together) - the latter has many advantages over the former. My puck/GPS is indispensable, however, I like the idea of RTL-SDR for AIS. Is it possible to trans/receive and not just receive?

USB to RS422/RS485: the issue here may be the number of USB slots! I have one for the mouse, one for the puck/GPS and one for the secure dongle which has my licensed charts on it. I have no USB slots available! This is on a Win10 laptop.

I have a Win XP Pro 3xthe weight of the W10, however it has RS422 and RS485 sockets. I also have a male/female dongle 422/485 which I use for Bonito98 which was connected to a SSB radio. Perhaps the RTL-SDR can be set up with the Bonito to get the frequency I require for AIS?!!!

With RTL-SDR and the small antenna, is it possible to clip a wire by dog clips to a back stay to get a better aerial?

Martin

[nohal]

Originally Posted by katoema

Throughout the year I have between 8-10 deliveries, depending on passage times. Most are at short notice, but the longer ones are known well in advance. Manuals are out of the question, but the owner is always asked if I can get into their NMEA.

I use both OpenCPN and qtvlm (not together) - the latter has many advantages over the former. My puck/GPS is indispensable, however, I like the idea of RTL-SDR for AIS. Is it possible to trans/receive and not just receive?

Only receive, of course.

USB to RS422/RS485: the issue here may be the number of USB slots! I have one for the mouse, one for the puck/GPS and one for the secure dongle which has my licensed charts on it. I have no USB slots available! This is on a Win10 laptop.

Get a (preferably powered) USB hub, problem solved.

I have a Win XP Pro 3xthe weight of the W10, however it has RS422 and RS485 sockets. I also have a male/female dongle 422/485 which I use for Bonito98 which was connected to a SSB radio. Perhaps the RTL-SDR can be set up with the Bonito to get the frequency I require for AIS?!!!


With RTL-SDR and the small antenna, is it possible to clip a wire by dog clips to a back stay to get a better aerial?

Get the $10 dongle from China everybody else uses and don't try to invent new wheels as the number of people able to help you with them will be low.
You can of course use whatever antenna, from the one that comes with the dongle to something like High Gain Collinear AIS (162MHz) Receiving Aerial
And of course for a little more money, you can have a real AIS receiver like https://www.tindie.com/products/astu...-ais-receiver/

[katoema]

https://www.ebay.co.uk/itm/USB-2-0-t...75.c100623.m-1

https://www.ebay.co.uk/itm/RTL2832U-...g27o:rk:2:pf:0

As I'm in the UK, are these two items what I require?

Martin