Dave, I have same config on my boat. This is correct, you'll need a protocol converter as the SeaTalk sentences are not directly translated to the NMEA bus. Then I wired it through my S3-G corepack. Again, it is good for NMEA-NMEA, SeaTalk-SeaTalk, but very limited to NMEA-Setalk and vice-versa. Some sentences present at SeaTalk are simply not forwarded to NMEA bus, and the oposit is true as well. I understand the private nature of SeaTalk, as some sentences has no equivalent at NMEA bus, but that should be true for the ones that have same correspondece in both sides. The
Raymarine converter will find same problem as well, but I expect it to have a larger range on information translated from/to NMEA.
Anyway, I found rasonable the amount of information available, but you should expect more. Hopefully NMEA 2000 will fix that
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