GPSMAP 750/Raymarine ST60 compatibility?

Plevier

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I fitted a GPSMAP 750 yesterday. Last stage was to connect its NMEA port 2, set to "NMEA standard", to the NMEA in and out connections on my ST60 Multi instrument, which is set to "NMEA out", not to external alarm. (I've used port 1 for the DSC, but only to it at the moment, I need to make a 4 wire cable.)
Data feed from the plotter is fine, the multi sees the GPS related inputs and transfers them to Seatalk so all the instruments get them.
However the plotter does not see any input from the ST60. Its diagnostics page resolutely reports nothing received.
Checking the manuals for both, the ST60 output matches the sentences that the plotter wants, the two lists are the same - depth, app wind, true wind etc. with the same 3 letter idents.
I didn't have time for any faultfinding, before I go back to it i wondered if anyone has coped with the same, or knows of some incompatibility that stops it working even though on paper it should?

I have a laptop (Vista) with a serial port, I believe if I connect the ST60 to that I can read it to check it's functioning. Can someone tell me how please? I think hyperterminal is the common way but Vista doesn't have it. In fact you can do a basic check that something is coming out with a multimeter can't you?

Thanks
 
I'm no expert and I am sure there will be one or two along soon, but in the meantime I'll chip in. I've just finished installing a GPSMAP 750 myself so some of the issues are fresh in my mind. In my case I have ST60 instruments and an ST400 Autohelm but I do not have the Multi so have had to add a Raymarine SeaTalk / NMEA converter. I've also added an AIS enabled VHF radio so I used the 750's port 2 for the AIS at 38.4k. NMEA from the ST60 stuff comes in on port 1 at standard speed (the brown wire on the 750) and I see everything I expected on the plotter including wind dials display and depth logging.

This may be obvious to you but just in case, Garmin does things slightly strangely in that all ground connections are combined together on the black wire, even the power supply.

You can only have one NMEA data stream going into any one port. In your case the output of the ST60 Multi counts as a single stream because it is a multiplexer I believe.

Couple of things in your post that I do not understand:

You mention DSC in and out. Does this imply that you have a VHF that can output DSC position data to the plotter? If this is so, I envy you, because I have come to the conclusion that my new RO4800 doesn't do this. DSC "out" in my case is simply position coordinates.

Also, you say "the Multi sees the GPS related inputs". Apart from position, what else do you envisage the ST60 making use of? Am I missing a trick?

Lastly, a suggestion: disconnect everything except the 750 power supply and the NMEA in from the ST60 and see what you get. That is, NMEA out from ST60 Multi to 750 thus:

ST60 out + ----- 750 port 2 in + (violet)
ST60 out - ------ 750 port 2 in - (black)

No need for PC based diagnostics, should work instantly, or not.
 
I'm no expert and I am sure there will be one or two along soon, but in the meantime I'll chip in. I've just finished installing a GPSMAP 750 myself so some of the issues are fresh in my mind. In my case I have ST60 instruments and an ST400 Autohelm but I do not have the Multi so have had to add a Raymarine SeaTalk / NMEA converter. I've also added an AIS enabled VHF radio so I used the 750's port 2 for the AIS at 38.4k. NMEA from the ST60 stuff comes in on port 1 at standard speed (the brown wire on the 750) and I see everything I expected on the plotter including wind dials display and depth logging.

This may be obvious to you but just in case, Garmin does things slightly strangely in that all ground connections are combined together on the black wire, even the power supply.

You can only have one NMEA data stream going into any one port. In your case the output of the ST60 Multi counts as a single stream because it is a multiplexer I believe.

Couple of things in your post that I do not understand:

You mention DSC in and out. Does this imply that you have a VHF that can output DSC position data to the plotter? If this is so, I envy you, because I have come to the conclusion that my new RO4800 doesn't do this. DSC "out" in my case is simply position coordinates.

Also, you say "the Multi sees the GPS related inputs". Apart from position, what else do you envisage the ST60 making use of? Am I missing a trick?

Lastly, a suggestion: disconnect everything except the 750 power supply and the NMEA in from the ST60 and see what you get. That is, NMEA out from ST60 Multi to 750 thus:

ST60 out + ----- 750 port 2 in + (violet)
ST60 out - ------ 750 port 2 in - (black)

No need for PC based diagnostics, should work instantly, or not.

Taking your paragraphs in order;
1 I was hoping to manage without the seatalk converter box. I don't have AIS.
2 Yes I have the NMEA grounds bonded to power ground.
3 Yes the ST60 multi is a single NMEA stream - not sure why you consider it a mux. It's just meant to be translating the ST bus I think.
4 Yes I believe my DSC radio (a Skanti/Sailor) does. The documentation is very poor but it has NMEA out connections. The 750 does envisage getting DSC position from the radio. Just looked at Furuno website, it says the RO4800 should do this.
5 The multi can take in and translates to the ST bus BWC, VTG, XTE, GLL, RMB and RMC. The 750 gives all of those. So as well as position I get waypoint name, distance, bearing, COG, SOG, time, date. I also have the ST60 graphic at the helm (the multi is at nav table) and on that I can simultaneously show brg & dist to wpt, COG and SOG, very useful when sailing for a mark. They also go to the ST4000+ autohelm over the ST bus.
6 That's exactly what I had - the violet and black and I even disconnected the DSC from port 1. Nothing. That's why I want to check if the multi is giving any output.
EDIT not quite true I had the grey connected to multi NMEA in as well.
7 It instantly does not work!!

I have one other possibility. The graphic is also supposed to give an NMEA output. However I've already found that its NMEA input only displays locally, doesn't translate to the ST bus (bit annoying as I've just bought it off the forum, but the seller may well not have known) so its NMEA output may be dead as well.

If both my NMEA outputs are dead then it's the converter box or do without ST parameters into the 750. Not sure how useful it would be anyway - what do you think is the big benefit?
 
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I have a laptop (Vista) with a serial port, I believe if I connect the ST60 to that I can read it to check it's functioning. Can someone tell me how please? I think hyperterminal is the common way but Vista doesn't have it. In fact you can do a basic check that something is coming out with a multimeter can't you?
It is important the ST60 Multi (and the PC) is set at the same Baud rate as the sender, check this first.

With a multi-meter set on a low voltage range you should see bursts of activity, or at least some fluctuation.

Connect the NMEA out of the device to the serial input on the PC: pins RxD (2) and Ground (5), see here: http://en.wikipedia.org/wiki/Serial_port#Pinouts

See below for list of HyperTerminal replacements, I recommend PuTTY:
http://en.wikipedia.org/wiki/List_of_terminal_emulators#Microsoft_Windows
 
I agree that you have no need of the converter, and I stand corrected regarding the ST60 Multi not being a mux, it just converts SeaTalk to NMEA. All hearsay for me as I don't have one.

I'm very interested in what you say about the DSC output from the radio. The RO4800 has wires designated as NMEA out but absolutely no details of what this might constitute. It sounds like your documentation is also vague. I can't find anything on the Foruno website about these VHF radios. Please send me a link as I'm probably looking at the wrong site.

To be honest, I had forgotten about the various data fields on the Autohelm display. I suppose it's because I have the chartplotter display at the helm and normally look at that. You are quite right of course that there is a lot of course /waypoint information generated from the plotter. I'll be having a go at getting this working on my next visit to the boat. With only one NMEA in port on the Raymarine converter I suppose I will have to choose between the doubtful radio output and the plotter output.

Anyway, none of this helps you with your issues. Borrowing a SeaTalk converter for a quick test would be useful. Pity you are nowhere near Troon as you would be welcome to try mine. You haven't mentioned setting the port speeds but I expect you know all about that. For the benefit of anyone else struggling with a 750, there are two ports and each can be set to standard or high speed but in and out speeds have to be the same for each port.

The benefit of getting SeaTalk data into the plotter for me would be depth logging (just for interest really), compass, windvane and log data for the plotter to be able to display navigation data fields, the stuff you are viewing on your Raymarine displays I suppose.

Not being an old sea salt, I like to see true wind which the 750 displays on a rose graphic centred on the boat.
 
It is important the ST60 Multi (and the PC) is set at the same Baud rate as the sender, check this first.

With a multi-meter set on a low voltage range you should see bursts of activity, or at least some fluctuation.

Connect the NMEA out of the device to the serial input on the PC: pins RxD (2) and Ground (5), see here: http://en.wikipedia.org/wiki/Serial_port#Pinouts

See below for list of HyperTerminal replacements, I recommend PuTTY:
http://en.wikipedia.org/wiki/List_of_terminal_emulators#Microsoft_Windows

Thanks. Yes appreciate about Baud rate. ST60 is fixed, garmin just gives you choice of high (for AIS) and standard.

Will try multi meter first.

Came across a prog called NavMonPC have you seen? Thought it looked impressive.
 
I'm very interested in what you say about the DSC output from the radio. The RO4800 has wires designated as NMEA out but absolutely no details of what this might constitute. It sounds like your documentation is also vague. I can't find anything on the Foruno website about these VHF radios. Please send me a link as I'm probably looking at the wrong site.

I found http://www.furuno.fr/Produit.php?&Page=Produits&Famille=13001&Produit=RO4800 and the manual at http://turbo36.files.wordpress.com/2013/01/furuno-ro4800-operators-manual.pdf

I may have misunderstood but it looks as though you use pins 7 and 8 for AIS output to the plotter at high rate and pins 1 and 2 for DSC output to plotter at standard rate. Means you have to use both plotter ports so I don't know how you would get your Raymarine signal in.

Could you feed the standard rate NMEA into the Ray box which would (might) then resend it muxed with the ST information to the plotter port 2 with AIS to port1? From the Garmin info it appears to be sentence DSC or DSE are those listed in what the Ray box will handle? I know it's pretty comprehensive.

PS see manual section 5.3.1 (1)
 
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I had a nightmare getting my RO4800 to transmit AIS data, which simply stopped when I connected my GPSMAP 750 to the sea talk converted to NMEA 0183 by my Tri data instrument, but this was due to a faulty RO4800 unit, which Force four replaced without any fuss under warranty.

I now have all three systems linked and working.

I used hyper terminal programme to determine the lack of NMEA from the RO4800. I also rewired the damn connections three times, and ended up making a junction box with individual multi pin plug/sockets from Maplins.

If you want more from my website downloads at turbo36.wordress.com please PM me for the download access password.
 
I found http://www.furuno.fr/Produit.php?&Page=Produits&Famille=13001&Produit=RO4800 and the manual at http://turbo36.files.wordpress.com/2013/01/furuno-ro4800-operators-manual.pdf

Could you feed the standard rate NMEA into the Ray box which would (might) then resend it muxed with the ST information to the plotter port 2 with AIS to port1? From the Garmin info it appears to be sentence DSC or DSE are those listed in what the Ray box will handle? I know it's pretty comprehensive.

PS see manual section 5.3.1 (1)

Thanks for that. I do remember reading that bit in the manual but it refers only to DSC distress data. It's not clear if ordinary position data is also sent. This makes it hard to test because, whilst I have a couple of replies to position requests in the DSC log of the radio, I may have to wait quite a while before I receive a distress message.

With reference to connecting the NMEA output from the 750 to the Autohelm, I've just remembered that the ST4000+ has it's own NMEA input, so that means I have sufficient ports. Something else to try. I have reservations about a likely conflict with the SeaTalk data though. Somewhere I read a post about disconnecting the SeaTalk connection to the ST4000+ to avoid this but from what I see in the manual the 750 does not send NMEA wind data.

Good point about the SeaTalk/NMEA converter, does it mux the SeaTalk IN and the NMEA IN? Anyone know?

Sorry about slightly hijacking your thread by the way.
 
Dammit I was thinking of my old Tosh I've only got USB now. Clever converter needed presumably? Or can it be done in software?

You could get a USB adaptor, but it hardly seems worth it just for testing. I could lend you one if you like, a USB adapter to three RS232 wires: Tx, Rx, and Gnd.

Just out of interest, do you see anything on the chart when you get a routine DSC call, or you request a position via DSC?

Not sure, never done either.
 
Thanks for that. I do remember reading that bit in the manual but it refers only to DSC distress data. It's not clear if ordinary position data is also sent. This makes it hard to test because, whilst I have a couple of replies to position requests in the DSC log of the radio, I may have to wait quite a while before I receive a distress message.

With reference to connecting the NMEA output from the 750 to the Autohelm, I've just remembered that the ST4000+ has it's own NMEA input, so that means I have sufficient ports. Something else to try. I have reservations about a likely conflict with the SeaTalk data though. Somewhere I read a post about disconnecting the SeaTalk connection to the ST4000+ to avoid this but from what I see in the manual the 750 does not send NMEA wind data.

Good point about the SeaTalk/NMEA converter, does it mux the SeaTalk IN and the NMEA IN? Anyone know?

Sorry about slightly hijacking your thread by the way.

I think only distress shows automatically but you can force a position display from a logged DSC call.
I don't think your concern about the ST4000 is right. Like the multi and the graphic it takes NMEA input and puts it onto the ST bus to share. Raymarine have told me only one instrument in a system should have an NMEA input to avoid confusion but obviously it needs the ST connected to share it.

Superheat6k should be able to help you more than me!
 
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I think only distress shows automatically but you can force a position display from a logged DSC call.
I don't think your concern about the ST4000 is right. Like the multi and the graphic it takes NMEA input and puts it onto the ST bus to share. Raymarine have told me only one instrument in a system should have an NMEA input to avoid confusion but obviously it needs the ST connected to share it.

Superheat6k should be able to help you more than me!

I think that the nature of the (possible) problem is "data looping". SeaTalk data arrives at the 750 from the converter, goes out to the ST4000+ as NMEA, gets converted, and back onto the SeaTalk bus. I can't remember where I read this but I think it was from a Raymarine techie. Soon find out when I try it next week.

How are you liking the 750 in general? I find it superior in almost every respect to the Raymarine C70 it has replaced which had a feeble display. My biggest worry was the touch screen but it seems to perform consistently. It didn't expect it to work with gloves but I found that the slightest amount of moisture on the end of a finger does the trick.
 
Don't follow that. The 750 won't retransmit anything received.I've found Raymarine on line support very responsive try them if in doubt. Found Garmin responsive too.
Not used it yet today will be first trial if I finish fitting it this morning.
 
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I connected my ST60 NMEA out to the garmin 4008. Nothing... the raymarine nmea isn't really nmea as other people know it. You need to spend oodles of dosh to buy a translator box of some sort. I didn't and won't.
 
raymarine nmea isn't really nmea as other people know it...

There may be something in this. When I connected a Raymarine SeaTalk to NMEA converter into my Standard Horizon plotter, I had to use a pair of resistors to reduce the voltage to about 5V. It seems that some Raymarine gear uses the older standard of 12V for a mark.

See: www.digitalmarine.kr/info/nmea/NMEA-0183-tech-information.pdf (you will need to download Korean font, but it is in English).
 
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