GPSMAP750 Bridging to NMEA 0183 - ST60 and ST1000+

chrisjrob

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Further to my recent thread on NMEA2000 and thanks to the advice received, I have now completed the installation of my GPSMAP 750, with dual positions - one in the cockpit and one at the chart table.

As outlined, I also laid an NMEA 2000 backbone, starting behind the switch panel, routing through the engine bay and terminating at the cockpit instrument panel, with drop cables connecting both positions to the backbone.

So I now have a working dual position 750 with a very expensive NMEA 2000 set-up, which enables it to mumble incoherently to itself, albeit really fast.

(BTW I am stunned by how good the 750 is. So user-friendly that you don't need a manual.)

I would now like to move this on to something which is actually communicating. My other equipment is:

  • Autohelm ST60 Tridata - Depth and Log
  • NASA Clipper - Wind
  • Raymarine ST1000+ Tillerpilot

I don't care about connecting up the Wind, but it would be useful to have the ST60 and ST1000+ connected.

I had believed that the only way that I would get any of this talking to the 750 was using Actisense NGW-1 adapters, which are fairly expensive at £100 or so each, but I noticed this weekend that the 750 includes a bridging mode, able to bridge between NMEA 2000 and 0183 networks.

It sounds like I need to get the ST60 and ST1000+ talking together with NMEA 0183 and then connect that up to the NMEA 0183 connectors of the 750. But I am making this up as I go along - can anyone confirm that to be the case?

Has anyone actually got the 750 bridging mode working?

Any pointers on how to connect this up - seems to be a bit of a mindfield?

Thanks,
 
I agree with you in liking the 750 - but Nigel thinks it has the worst user interface ever invented!

I'm not sure what NMEA data you are trying to get to what.
You can go straight from the 750 NMEA 0183 output to the ST1000 input, just as I have done to my ST4000+.
It may be that the ST1000 will translate the NMEA input onto the SeaTalk bus. The ST4000 does but the ST1000 manual is not specific about it.
But what do you want to transfer to the tridata?
The ST60 tridata does not offer NMEA in or out only Seatalk.

Or, are you hoping to get depth etc into the 750?
That is much harder because the 750's NMEA 0183 input is rather nasty with one side grounded and it won't work with Raymarine's NMEA output (which I think is only fitted on the multi and the graphic anyway) without some adaptation. Nigel has suggested a way, i haven't had time to try it yet and I'm waiting for a response from Garmin too.
I think you would need to get one of Raymarine's SeaTalk to NMEA boxes. I don't know whether the output of that could go straight to the 750 or whether it is also incompatible with the 750's one side grounded input.
 
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You can go straight from the 750 NMEA 0183 output to the ST1000 input, just as I have done to my ST4000+.

And I should then be able to drive the tillerpilot from a route on the 750? That would be fantastic.

It may be that the ST1000 will translate the NMEA input onto the SeaTalk bus. The ST4000 does but the ST1000 manual is not specific about it. But what do you want to transfer to the tridata?
The ST60 tridata does not offer NMEA in or out only Seatalk.

Ah, I'd assumed that they both natively talk NMEA 0183, I should have checked that. That's the problem with standards - there are so many from which to choose!

Or, are you hoping to get depth etc into the 750?

Exactly so, the 750 conveniently shows the outputs on the screen, which would be "nice" although hardly essential.

That is much harder because the 750's NMEA 0183 input is rather nasty with one side grounded and it won't work with Raymarine's NMEA output (which I think is only fitted on the multi and the graphic anyway) without some adaptation. Nigel has suggested a way, i haven't had time to try it yet and I'm waiting for a response from Garmin too.
I think you would need to get one of Raymarine's SeaTalk to NMEA boxes. I don't know whether the output of that could go straight to the 750 or whether it is also incompatible with the 750's one side grounded input.

It sounds like I should concentrate on getting the ST1000+ working and then consider buying one of those Seatalk/NMEA bridge for the ST60, if I'm really desperate to get the depth and log displaying on the 750.

Thinking about it, my ST60 does have some moisture in it and a somewhat glazed screen - is it possible to replace the display with something newer that would talk to the existing transducers? And if that were NMEA 2000 compatible so much the better.

Thanks for the advice.
 
:)
Not quite what I said, I'm only going by my experience of one Garmin plotter, and a few hand-held devices. Perhaps if you get Garminese it is simple.

I never liked Garmin myself, finding their interfaces generally clunky and unintuitive. I can't say the same about the GPSMAP 750. The only criticism I can find is that Routes wasn't exactly where I expected it, but it wasn't hard to find.
 
And I should then be able to drive the tillerpilot from a route on the 750? That would be fantastic.



Ah, I'd assumed that they both natively talk NMEA 0183, I should have checked that. That's the problem with standards - there are so many from which to choose!



Exactly so, the 750 conveniently shows the outputs on the screen, which would be "nice" although hardly essential.



It sounds like I should concentrate on getting the ST1000+ working and then consider buying one of those Seatalk/NMEA bridge for the ST60, if I'm really desperate to get the depth and log displaying on the 750.

Thinking about it, my ST60 does have some moisture in it and a somewhat glazed screen - is it possible to replace the display with something newer that would talk to the existing transducers? And if that were NMEA 2000 compatible so much the better.

Thanks for the advice.

You can certainly drive the ST4000 to track to a waypoint and I think it can follow a multi waypoint route. I can't speak for the ST1000 but why else would it have an NMEA0183 input? I'm sure the manual will tell you (there is a short acronym for that!)
Don't take it for granted that Raymarine's adapter box will work with the 750. If they have done it the same funny way as the ST60 NMEA output, then combined with Garmin's nasty input, it won't. If they have done it properly, it should cope with Garmin's tricks.
Can't answer your last question but maybe Raymarine's latest range would?
 
Maybe it's because the first GPS I had was a Pilot III, then a 152, now the 750.
Some things do seem to take rather a lot of button presses, but it's all pretty straightforward IMO.
I find Raymarine much harder.
The electronic - as opposed to user - interface is pants though! Just penny pinching I think.
 
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