6 NMEA0183 devices - multiple multiplexers

[sv_isara]

Hey all,
I have a boat made in the 90s, with items such as a Garmin GPS Map 182C, and other things of a similar vintage. The boat is an 11 hour drive away so I won't have the ability to get the exact models of all the other electronics for a few weeks.

My goal is to hook everything up to an android tablet and opencpn and hopefully be able to program waypoints etc. My question is - all the articles I've seen have referenced hooking up only up to 4 nmea0183 devices to a multiplexer. Online, the mux devices which I have seen only have up to 4 inputs.

How would I then get data from 6 instruments to a multiplexer and then to a wifi network to the tablet? Do i need to chain 2 multiplexers together (ie anemometer + depth +speed to mux1. Mux1 sent to mux2 which muxes mux1 + gps + ais + autopilot)

Thanks for any help or direction.

devices:

Autopilot
GPS (I believe i have stand-alone GPS receivers)
Anemometer
Depth
Speed
AIS

[HeywoodJ]

Your autopilot probably wants to be a listener, so that goes on the talker channel from the mux. Your AIS (if it is a transponder) can provide GPS data (it has to have a GPS, haven’t seen one yet that didn’t put that out on NMEA). That would leave you with 4 ins and 1 out, so would likely work with a single mux.

Two if your AIS is receive-only, or if you really want data from the GPS as well. If they both output WiFi then connect them to the same network and set up your system to listen to both of them. Otherwise you could daisy-chain as you suggested, although some risk of congestion on the final uplink.

[smac999]

The speed, depth, and wind are Likly networked to a brain and then has a single nmea 183 output? I’ve never seen induvual gauges each with own nmea 183 output.

[sv_isara]

Originally Posted by HeywoodJ

Your autopilot probably wants to be a listener, so that goes on the talker channel from the mux. Your AIS (if it is a transponder) can provide GPS data (it has to have a GPS, haven’t seen one yet that didn’t put that out on NMEA). That would leave you with 4 ins and 1 out, so would likely work with a single mux.

Two if your AIS is receive-only, or if you really want data from the GPS as well. If they both output WiFi then connect them to the same network and set up your system to listen to both of them. Otherwise you could daisy-chain as you suggested, although some risk of congestion on the final uplink.

Got it, yes that helps a lot. For what it's worth I have a Raymarine S1 smartpilot as the autopilot waiting to be hooked up.

Originally Posted by smac999

The speed, depth, and wind are Likly networked to a brain and then has a single nmea 183 output? I’ve never seen induvual gauges each with own nmea 183 output.

Yeah that's what I see on diagrams around the net. All I know is they're probably 90s era units. The original autopilot was a autohelm ST6000 with a below-decks hydraulic piston type unit.

[sv_isara]

Here are pics of the instruments. Note that the B&G network vhf unit on the bottom right side is not hooked up.

[hoolie]

I think you'll find the Autohelm instruments use a SeaTalk bus and don't have NMEA 0183 connections. So you'll need a converter as well. Shipmodul multiplexers inputs can be configured as one SeaTalk bus and three 0183 connections. A single SeaTalk bus will carry all the data from the Autohelm instruments.

[sv_isara]

Originally Posted by hoolie

I think you'll find the Autohelm instruments use a SeaTalk bus and don't have NMEA 0183 connections. So you'll need a converter as well. Shipmodul multiplexers inputs can be configured as one SeaTalk bus and three 0183 connections. A single SeaTalk bus will carry all the data from the Autohelm instruments.

Great news thank you!