Open CPN and an external GPS source

[sarabande]

I have a Panasonic Toughbook with the latest version of CPN on it plus UK charts. And a small Garmin Etrex.

Despite my best endeavours, I cannot get the laptop to read data from the Etrex (which I know works properly when disconnected ). Should I download Google Earth, to prove that the Garmin will speak to the computer ?


Can some kind soul point me in the right direction please ?

 

[CCJ]

i use a gps dongle stuck inside the saloon window, it works just as well as the raymarine one on the stern rail

Have you "told" the cpn what port to use

 

[RobbieW]

How is the etrex being connected to the laptop ? Assuming Serial/USB converter and Windows, check in the Device Manager to see which Com port its using then try both 4800 and 9600 in the OCPN settings. Again, assuming Windows, you will want to turn 'enumeration' off in the USB/Serial device settings because there is a risk the OS will see the etrex as a serial mouse and send the pointer jumping all over the screen

Edit: I vaguely remember having to set the speed using Device Manager in the past, oh and the enumerator setiing will be found through device manager

 

[prv]

Should I download Google Earth, to prove that the Garmin will speak to the computer ?

Better would be to open the serial port with some terminal program (I'm not a Windows user but I believe Hyperterminal is the thing, or possibly RealTerm?) and see whether readable NMEA0183 strings are coming through. If you see nothing at all then there's a problem with the wiring or the GPS isn't sending anything (or you haven't opened the right port correctly...), if you see bursts of garbage characters then everything's more or less right except that the baud rate is wrong. Your terminal program should be able to try different speeds until you start seeing readable data, then make sure that's what you have set in OpenCPN.

Pete

 

[agurney]

..you have of course checked that you're outputting NMEA and not Garmin format?

Google Earth won't help you, openCPN is far better at helping with setting up the serial connection. Enable "show NMEA debug.." under "Connections", and adjust the settings until you see the messages coming through. Ensure no other applications are trying to access the device.

I use an old eTrex occasionally, IIRC it has a limited set of baud rates.

 

[lpdsn]

The OpenCPN NMEA debug window will tell you whether anything at all is coming through, even garbage.

You can put Wireshark on the PC to see if you are getting any sort of communication with the eTrex.

 

[agurney]

The OpenCPN NMEA debug window will tell you whether anything at all is coming through, even garbage.

You can put Wireshark on the PC to see if you are getting any sort of communication with the eTrex.

The debug window only shows the NMEA sentences, not the 'garbage' from incorrect settings.

Wireshark won't help with the serial interface.

 

[david_bagshaw]

a little prog called gps port checker, is particularly helpful.

http://www.oziexplorer3.com/utils/gps_port_checker.html

 

[sarabande]

Thanks everyone. The laptop decided that it really really needed to update Win10 to the latest service number, so has been talking to itself all day.

With a bit of luck, it will allow me to play tomorrow.

 

[fergie_mac66]

Unless you got meltdown!

 

[CCJ]

Thanks everyone. The laptop decided that it really really needed to update Win10 to the latest service number, so has been talking to itself all day.

With a bit of luck, it will allow me to play tomorrow.

6 pence says it will revert to previous :disgust:

 

[RobbieW]

Thanks everyone. The laptop decided that it really really needed to update Win10 to the latest service number, so has been talking to itself all day.

With a bit of luck, it will allow me to play tomorrow.

All day is rather too long - slow comms ? defrag ? slow disk ?

 

[Hoolie]

All day is rather too long - slow comms ? defrag ? slow disk ?

Not with the Fall Creators update 1709. Most of my PCs took several days, even weeks to finally successfully install this update. On one it broke something and I had to do a complete Windows re-install

I don't know about the Etrex, but the Garmin GPS 152 has a choice of protocols - NMEA 0183 or "Garmin". OpenCPN will take either but you have to configure it for "Garmin" on the connections tab. The proprietary protocol has better route transfer capabilities.

 

[RobbieW]

Not with the Fall Creators update 1709. Most of my PCs took several days, even weeks to finally successfully install this update. On one it broke something and I had to do a complete Windows re-install

Fair enough, but by contrast none of the 3 or 4 machines I've done have taken more than 2 or 3 hours for 1709. Not all based on fresh installs either, at least one was a Win 7 upgrade during the amnesty period