Problem connecting Garmin to Raymarine

[Bloater]

I have replaced most of the Raymarine kit on my boat with Garmin electronics. I have kept the ST50 wind and Tridata instruments as they are working perfectly. I now have a Garmin 4010 chartplotter.

In order for them to talk together I have also purchased a Raymarine E85001 interface black box.

I have a problem in so far as the Garmin plotter does not display the depth at all. Looking at the received NMEA data the Raymarine interface is only transmitting the DBT sentence and not the DPT one as well (DBT = depth below transducer, DPT = depth).

It appears that the chartplotter is displaying only the DPT and I can't get it to display the received DBT data.

So my question is, had anyone else had a similar problem displaying depth using a Garmin plotter with Raymarine instruments using the E85001 interface? If so how did you get around the problem?

 

[earlybird]

If I correctly understand the owner's manual that I have for the Raymarine interface, only DBT is converted from seatalk and transmitted as NMEA.
The device does seem receive DPT in NMEA however, but that isn't what you want of course.

 

[pvb]

It appears that the chartplotter is displaying only the DPT and I can't get it to display the received DBT data.

The 4010 plotter is supposed to support both DBT and DPT sentences. Have you gone into the NMEA0183 setup menu and configured it to include DBT?

 

[Playtime]

It appears that the chartplotter is displaying only the DPT and I can't get it to display the received DBT data.

So my question is, had anyone else had a similar problem displaying depth using a Garmin plotter with Raymarine instruments using the E85001 interface? If so how did you get around the problem?

I've got a similar set-up but the combined mux output is fed to a PC not to a Garmin plotter. The PC can read the DBT sentence.

The format of the 2 sentences (DBT and DPT) is not the same. As you rightly say, Seatalk only outputs the equivalent of DBT and that is what the mux will push out in NMEA format. You don't say which Garmin plotter you are trying to interface to but I assume you have checked that it does not read the DBT sentence.

There are 'intelligent' muxes around (like this one) that can be programmed for protocol conversion (i.e. change DBT to DPT) but it is not simple (unless you have a background in software).

 

[Bloater]

Hi, the Garmin is stating that no DPT data is being received, this is because only the DBT is being transmitted from the Raymarine interface. The problem is that I can't make the Garmin display the depth on screen using just DBT information.

 

[ianj99]

There are 'intelligent' muxes around (like this one) that can be programmed for protocol conversion (i.e. change DBT to DPT) but it is not simple (unless you have a background in software).

I think only the talker ID can be changed, not the sentence formatter.
This is also the case with my Miniplex 2usb from Shipmodul.

So you change SDDPT to xyDPT - ie you can change the first 2 ID letters, but there is no option to change DPT to DBT. (or vice versa).

The reason is obvious - the data is not the same.

 

[Playtime]

I think only the talker ID can be changed, not the sentence formatter.
This is also the case with my Miniplex 2usb from Shipmodul.

So you change SDDPT to xyDPT - ie you can change the first 2 ID letters, but there is no option to change DPT to DBT. (or vice versa).

The reason is obvious - the data is not the same.

If you read this page for the Brookhouse mux you will see that you can change the sentence type and data parameters. It gives the following as an example

Conversion of depth sounder sentences DPT to DBT, DBS to DBT, etc.

but, as I said, it is not simple!