Route Information to Autopilot

[sinbad7]

This has probably been posted somewhere previously,but I ask again:

Having created/plotted a route in OCPN, is it possible to feed the .gpx route info to an autopilot in a standard NMEA format?

Tore

[BoomBrake]

Yes it does. You need to find more information about your setup to answer this. Like all software to electrical systems interfacing, it I can get complicated. Of course if you already have the latest and greatest kit, setup correctly it could be fairly simple. Specific configuration varies depending on your kit...

What is the the make/model of your Chartplotter, does it support NMEA2000 or only NMEA0183? What hardware is OpenCPN interfacing to the Chartplotter on, serial, USB and any custom pinouts?

I suggest that you do some research on the OpenCPN website at the basic configuration GPS page http://opencpn.org/ocpn/setting_up_gps they have many options that vary depending on your setup and interfacing configuration. Also suggest you so some more searching on cruiserforum specific to your Chartplotter and NMEA version, as there is also quite a lot of detail available depending what your kit is.

Or if you're in Sydney Australia, I'll come to your boat and configure it for a small fee!

[andreanuzzo]

Hi all,
I just purchased an ocean 430 and I found on it an Autohelm st7000 with the Autohelm 100/300 course Computer. I would love to interface it with my win7 laptop running OpenCPN in order to make OpenCPN drive my autopilot.
Here are my two questions:
1) Could you please advice what hardware interface should i purchase to connect the laptop to the Seatalk Network?
2) I noticed on the autohelm 100/300 course computer a nmea input output. Is it possible to directly connect that to my laptop?
Thank you for your help.
a

[bobofthenorth]

Originally Posted by andreanuzzo

Hi all,
I just purchased an ocean 430 and I found on it an Autohelm st7000 with the Autohelm 100/300 course Computer. I would love to interface it with my win7 laptop running OpenCPN in order to make OpenCPN drive my autopilot.
Here are my two questions:
1) Could you please advice what hardware interface should i purchase to connect the laptop to the Seatalk Network?
2) I noticed on the autohelm 100/300 course computer a nmea input output. Is it possible to directly connect that to my laptop?
Thank you for your help.
a

Can't help on question #1 except to ask the obvious - why do you want to do that?

As far as #2 question goes the answer is YES. The exact methodology is a bit complicated but its not rocket surgery either. If your laptop has an actual DB9 com port then its pretty simple. If (more likely) you only have USB ports to work with then you'll first need a USB to COM adapter cable which will cost you in the neighbourhood of $20 at your local Radio Scrap.

Once you have a DB9 connection to work with, refer to the attached images. Note that the common ground is essential. You absolutely need to connect the com ground to the ground on your autopilot.

You'll need to configure the connection (wrench icon) to be output - I'd actually advise making it output/input so that OCPN can receive heading information from the autopilot. Initially I had difficulty figuring out how to configure an output connection because you need to scroll down in the setup window - the output option is not immediately visible. You'll likely need to plug in your cable first and then start OCPN in order for it to see the port so that you can then configure the port. After you make the physical connection then you need to create and activate a route in OpenCPN.

At this point all that should remain is to put your Autohelm into whatever its version of autonav mode is. You're on your own for that but I assume you have an Autohelm manual. OCPN provides a debug screen to see the input/output stream if you need to troubleshoot your installation. We use a similar system to drive a Cetrek autopilot every time we leave the dock. Other than my sometimes flaky HP touchscreen that occasionally craps out, the system is dead reliable and dead simple.

[andreanuzzo]

Originally Posted by bobofthenorth

Can't help on question #1 except to ask the obvious - why do you want to do that?

As far as #2 question goes the answer is YES. The exact methodology is a bit complicated but its not rocket surgery either. If your laptop has an actual DB9 com port then its pretty simple. If (more likely) you only have USB ports to work with then you'll first need a USB to COM adapter cable which will cost you in the neighbourhood of $20 at your local Radio Scrap.

Once you have a DB9 connection to work with, refer to the attached images. Note that the common ground is essential. You absolutely need to connect the com ground to the ground on your autopilot.

You'll need to configure the connection (wrench icon) to be output - I'd actually advise making it output/input so that OCPN can receive heading information from the autopilot. Initially I had difficulty figuring out how to configure an output connection because you need to scroll down in the setup window - the output option is not immediately visible. You'll likely need to plug in your cable first and then start OCPN in order for it to see the port so that you can then configure the port. After you make the physical connection then you need to create and activate a route in OpenCPN.

At this point all that should remain is to put your Autohelm into whatever its version of autonav mode is. You're on your own for that but I assume you have an Autohelm manual. OCPN provides a debug screen to see the input/output stream if you need to troubleshoot your installation. We use a similar system to drive a Cetrek autopilot every time we leave the dock. Other than my sometimes flaky HP touchscreen that occasionally craps out, the system is dead reliable and dead simple.

Dear Bob,

thank you so much for taking the time to explain the connection. Though, you are talking to a dummy here and I don't want to kill my course computer!

On the course computer I have connections as shown in the picture and it is not clear to me what goes where...

whould you be up for an extra help?

Again, thank you for your time,

Andrea

[bobofthenorth]

Sorry about the delayed response. We were in Glacier Bay until yesterday and I'm reading this on my phone tonight. I'll look at your drawing in the morning and (perhaps) respond more intelligently.

[andreanuzzo]

HI Bob,
Your reply was indeed intelligent! It is my fault, I’m terrible with hardware!!!
Take your time; it is not urgent at all. Now my boat is in Greece and I am in Italy dealing with bureaucracy to change from Italian to Belgian flag…
Grazie,
Andrea

[smac999]

nmea in - to pin 5 on pc serial cable
nmea in + to pin 3 on pc serial cable

easiest is to buy a serial cable and cut one end off. you'll probably need a multi meter to ohm out which wire is which pin.

[bobofthenorth]

Andrea it appears that your connections 1 & 2 are listeners (NMEA in) and your connections 3 & 4 are talkers (NMEA out). The original terminology was "talker" and "listener" - I sometimes find that wording less confusing than "in" and "out" terminology which changes for the same wire depending on which end of the cable you are referring to. Talker and listener implies the same change over the length of the cable but it seems easier to understand for me anyway. You will end up with an OpenCPN "talker" port at one end of one wire in your serial cable connected to an autopilot "listener" port at the other end of the same wire and vice versa.

So what you need is:
- hook your (-) terminals (2 & 4) to pin 5 on the serial cable.
- connect your OpenCPN talker which should be pin 2 on the serial cable to the listener port (1) on your autopilot
- connect your OpenCPN listener which should be pin 3 on the serial cable to the talker port (3) on your autopilot

I realize that's not what smac999 just told you to do but I think that advice is wrong. However, there's nothing to lose - both of us agree to connect the (-) terminals to pin 5. The only question is how to hook up ports 1 & 3 on your autopilot to pins 2 & 3 on the serial cable. There's only 2 ways to do that and you won't hurt anything by hooking them up reversed - it just won't work. So try it one way and if that doesn't work, switch the connections. This stuff used to scare the crap out of me too but after a while you get into the spirit of trying to make it work and it kind of becomes fun. Try to enjoy the journey.

[andreanuzzo]

Bob,
Thank you again for taking the time to answer. Everything looks clear to me now!
Now I only need to set myself in a ZEN mode and wait for the Italian bureaucracy to release the Italian flag for my newly purchased Oceanis 430. I strongly advice everybody to stay away from the Italian bureaucracy!!!
I will keep everybody posted on the development of the system on the boat.
Grazie,
andrea

[Tupaia]

Originally Posted by sinbad7

Hi all,
I just purchased an ocean 430 and I found on it an Autohelm st7000 with the Autohelm 100/300 course Computer. I would love to interface it with my win7 laptop running OpenCPN in order to make OpenCPN drive my autopilot.
Here are my two questions:
1) Could you please advice what hardware interface should i purchase to connect the laptop to the Seatalk Network?
2) I noticed on the autohelm 100/300 course computer a nmea input output. Is it possible to directly connect that to my laptop?
Thank you for your help.
a

Hi Andrea, just picked up on your question. I have an "almost" identical setup and the instructions given to connect everything together are fine. Once you have done it you will wonder why you thought it was complicated.

Qu#1 - Raymarine produce an interface box part #E85001 that converts Seatalk to NMEA and visa versa that gives access to some otherwise unavailable information.

Have fun with you new boat.

Peter