+- OpenMarine (https://forum.openmarine.net)
+-- Forum: OpenPlotter (https://forum.openmarine.net/forumdisplay.php?fid=1)
+--- Forum: How do I...? (https://forum.openmarine.net/forumdisplay.php?fid=3)
+--- Thread: Setting up a system with Seatalk instruments (/showthread.php?tid=4444)
Setting up a system with Seatalk instruments - Elmumu - 2023-01-27
hello folks
I'm new here. Just boat my sailboat a month ago, and going the DIY route with the navigation system. I have an old Raymarine installation, consisting of a St30 bidata speedo / depth , an anemometer, and a autohelm st4000 pilot.
My goal is to feed all of them in Openplotter. Question is, is it possible to link the seatalk bus to a multiplexer and get all the data correctly in openplotter ? I know this is some really old stuff, but all the instruments are working so why replace them.
Help would be much appreciated
Thanks
RE: Setting up a system with Seatalk instruments - jim321 - 2023-01-27
https://www.youtube.com/watch?v=XFOGrBmDhJg&ab_channel=SmartSailingBoat
https://openplotter.readthedocs.io/en/latest/description/how_does_it_work.html#seatalk1
RE: Setting up a system with Seatalk instruments - abarrow - 2023-01-27
Yes, using OpenPlotter GPIO you can take a feed from your SeaTalk network and bring the data into OpenPlotter. You can't go both ways, just Seatalk -> Openplotter (SignalK). You don't need any sort of multiplexer, just connect to the SeaTalk bus.
It requires a fairly simple signal level converter to bring the 12V Seatalk to the TTL levels that GPIO expects. These work well, but you do have to change a resistor: https://smile.amazon.com/gp/product/B01L1OI1HC/?th=1
RE: Setting up a system with Seatalk instruments - Sailabout - 2023-01-30
You can also use a cheap multiplexer – about 55 Euro – like the Nmea3Wifi or Nmea4Wifi. The first one has SeaTalk 1 bidirectional capabilities and the second one only SeaTalk 1 to NMEA0183 capability, both from, www.vela-navega.com.
RE: Setting up a system with Seatalk instruments - Elmumu - 2023-01-31
Thanks for your answers !
If i got it correctly : if i plug the seatalk wires directly to the Pi's GPIO , i'll get the data but won't be able to send.
But a multiplexer could do bidirectionnal data tranfer.
By bidirectionnal, does it mean i can control the pilot in Openplotter ?
RE: Setting up a system with Seatalk instruments - jim321 - 2023-01-31
"if i plug the seatalk wires directly to the Pi's GPIO".
dont do that its 12v it will fry your pi.
RE: Setting up a system with Seatalk instruments - Elmumu - 2023-01-31
Yes sorry I was meaning no multiplexer in between. An optocoupler should do the trick to get the signal from the seatalk instruments to PI's GPIO
RE: Setting up a system with Seatalk instruments - jim321 - 2023-01-31
https://actisense.com/news/understanding-different-protocols-seatalk/
RE: Setting up a system with Seatalk instruments - we9v - 2023-02-28
(2023-01-31, 12:04 PM)Elmumu Wrote: If i got it correctly :
But a multiplexer could do bidirectionnal data tranfer.
Bidirectional is possible in SOME multiplexers. Many are only one-way. Here's a few that are bi-directional:
https://yachtdevicesus.com/products/nmea-2000-router-ydnr-02-w-nmea-0183-seatalk?_pos=7&_sid=17498828f&_ss=r
https://shipmodul.com/miniplex-3.html
https://digitalyachtamerica.com/product/st-nmea-usb/
RE: Setting up a system with Seatalk instruments - Techstyle - 2023-02-28
What I have done is use an optocoupler to the Pi to receive Seatalk from the gauges and then connected via a USB to RS422 to send data via NMEA0183 to my ST4000 autopilot, that has a NMEA0183 input on the back.