OpenCPN, com ports, autohelm - help please?

[pir8ped]

Hi,

Can someone help me get my laptop running OpenCPN to connect to my Autohelm S2000+ so that I can send a route to the Autohelm and have it run in track mode?

I have a couple of things already connected to the laptop via USB - a depth sounder and an AIS. I use a USB hub, and these things have been working fine for years. So I've tried adding a new USB connection from the hub to the Autohelm. I've cut the end of the USB cable and connected the red and black wires to a length of two-core that runs to the Autohelm deck fitting. The two core connects to sockets 5 and 6 in the Autohelm deck connection, as instructed in the Autohelm manual.

I get 5v or so across these wires.

When I first connected the Autohelm and switched on, a new com port appeared in Device Manager (com3), and right clicking on an active route in OpenCPN gave me the option of sending the route to the Autohelm. I tried that. The Autohelm display showed a 't' and the course, and then the bunch of symbols the manual tells me means 'Track data not received'.

A further attempt later crashed OpenCPN, and when checking in Device Manager for com3 I could see it only when I clicked on 'Show hidden devices'. I've tried uninstalling com3, hoping switching on the Autohelm while it was connected to the laptop would result in the recreation of the com port, but that didn't work.

Any advice would be most welcome.

Thanks,

John Pedersen

[bcn]

Your OS (Windows ?) and the version of OCPN your using?

[pir8ped]

Sorry, windows 7 and opencpn 4.0.0

[bcn]

Next would be the OCPN log file. You can try with the USB attached and without to see what OCPN sees.

[Hakan]

John
If you have the AP 2000 I think the advised socket connections, NMEA+/NMEA-, is not an USB connection but a (old fashioned?) serial RS232. To connect it to your PC's USB you need a "serial to USB" converter (or if you (unlikely) happens to have a serial port on the PC use that (pin 3 and 5)).
Please revert if you need more details.
Håkan

[pir8ped]

I've just left the boat, before I got your message suggesting trying with and without the USB connected.

But attached is today's log from OpenCpn. I see the program 'thinks' it is sending data to the Autohelm. I don't know if there is any handshaking or feedback involved so that openCpn 'knows' whether the data has been received.

I'll try what you asked when I get back to the boat.

Thanks,

John

(I haven't attached a file on this forum before. Just today's log file is 23 kb, and I get a message saying the limit for a txt file is 1 kb... seems a very small limit?)

[pir8ped]

Hakan,

That sounds like a good lead. My depth sounder is attached to the laptop via a serial to USB converter. I'll take another look at that and try what you've suggested.

Thanks very much.

John

[bcn]

Rename the log to .doc before uploading. Does accept larger files then.

[pir8ped]

OK, hopefully I've attached the file OK.

[pir8ped]

Sorry about the time lapse - I've been sailing.

I'm still unable to send a route to my AP.

I have fitted a usb to serial adapter, and connected pin 3 to the NMEA+ and pin 5 to NMEA-.

The USB to serial adapter is installed on com9, and seems to be working fine.

However, when I try to send a route from opencpn to the AP, I get a message on the AP screen saying that no data has been received.

Looking in the opencpn log, I can see that data has been sent through com9, but the NMEA sentences start with either ECWPL or ECRTE. These are the only sentences sent.

According to my Autohelm 2000 manual, these sentences are not recognised by the AP. (There is a list of the recognised sentences on page 47 of the manual).

In opencpn, in the properties section for com9, I have ticked the box marked 'output on this port (as autopilot or NMEA repeater).

Any suggestions?

Thanks.

[Neptune's Gear]

Serial data needs to have the baud rate, and other parameters set correctly to allow the connection to be successful. Standard NMEA0183 is 4800, 8,N,1
Check the AP manual to get the required parameters, otherwise use those above. You can set the speed - baud rate - in opencpn, but the rest should be set in windows.

[pir8ped]

I have the baud rate set as you've suggested. I don't think this is the problem.

What about the NMEA sentences? It looks like opencpn is sending only sentences that the AP doesn't handle.

Have other people succeeded in getting opencpn working with an Autohelm ST2000?

Thanks.

[Hakan]

pirSped...
I'm not sure the AP can handle a route. I suppose you want to follow a route made in OCPN? In that case the method is to activate the route in OCPN. Then O will start to send data for next WP to navigate to. Once received your AP will understand these NMEA messages that O will send.
When the route is activated in OCPN put your AP in automatic or manual track mode as described in your manual page 15.
Whether your AP will understand the course change after a WP is received and continue to next I don't know. Maybe you have to acknowledge the course change, as I have to do with my, WP30, AP.
Good luck/Håkan

[Shipraiser]

Originally Posted by pir8ped

Looking in the opencpn log, I can see that data has been sent through com9, but the NMEA sentences start with either ECWPL or ECRTE. These are the only sentences sent.

That won't work with an old autopilot. Usually **APB sentence works best.

/Marcus