I have an older Standard Horizon DS50 transducer and depth display. The display has an NMEA 0183 output. I hooked that to an AT10 and the AT10 to my backbone. I can see the Depth coming through on the network as viewed via the MAretron USB Gateway and the N2KAnalyzer. I can also see it via the Actisense NGT gateway and the Actisense NMEA Reader.
But the Maretron DSM250 isn't displaying any depth information.
I sent this in to Maretron Support but I thought I'd drop a note here as well since I see some others have used the AT10.
Thanks,
-p
If it helps the DPT line that I see when I did a capture with NAVMonPC looks like this:
$IIDPT,5.33,,*77
-p
The missing transducer offset in the DPT line means the AT10 doesn't transmit an offset which is 100% correct. I've verified that this is the case by analyzing the output of an AT10.
If the DPT line contains an offset then the AT10 will send out one as well, and it might be that this triggers your DSM250 to show depth.
Originally I did not have an offset configured. I set one and watched the traffic with Actisense NMEAReader. I do not see the offset coming through or the primary depth data being modified.
I sent a Maretron N2KAnalyzer boat file to Maretron support for them to analyze. Seems like maybe I need to talk to Simrad who makes the AT10.
-p
Just as an FYI, the NavMonPC author says his program will not work if the offset isn't passed too. He's going to fix that. I'm not sure what is up with the MAretron DSM250 yet, might be the same issue as you suggest.
-p
Before you do analyse the NMEA 2000 bus any further I would make sure that you get an offset in the NMEA 0183 stream.
I think it is a mistake on the display side that they don't show anything if they don't get an offset. My IS20 displays show a "keel" icon when the offset is null or positive and a "water" icon when the offset is negative.
The latest version of NavMonPc (v1.06, http://www.navmonpc.com) will accept the DPT message with a missing offset.
Just wanted to follow-up a bit on this. Tonight I attached the Standard Horizon DS50 directly to an Actisense NGW-1 (0183 to 2000) and recorded the data with NavmonPC as the data came through the Maretron USB100.
The offset is still missing, so it's not the AT10. I assume the DS50 isn't sending it at all, OR the Actisense is stripping it as well.
The same things is true for the data I see via Actisense NMEAReader connected to the Actisense NMEA 200 USB gateway.
I'm thinking the bug here is the missing offset AND the MAretron DSM 250 not showing the depth when that happens.
-p