Objective of NMEA
"luc" wrote in message
oups.com...
I am an NMEA neophyte. I am trying to connect my Raymarine speedo,
depth, and wind indicator. They use SeaTalk. Apparently, SeaTalk is
not NMEA language. I thought the point of NMEA was to make multiple
manufactures equipment communicate, much like MIDI (musical instrument
digital interface) works for electric guitars, keyboarsd, and
synthesizers.
I have a Garmin GPS, which does have some NMEA capabilities. I would
like to connect it to my ICom VHF, for the DSC feature. I would also
like to connect my sounder to the GPS to show depth on the Garmin. Is
this possible? Does anyone know where to get more information about
NMEA and connecting these various devices? I've already learned a bit,
but have a long way to go.
You could connect the NMEA output from the GPS to the NMEA input of the VHF
and at the same time connect the NMEA output from a sounder to the NMEA
input of the GPS.
If your sounder is part of the Raymarine setup, you can use one of my
multiplexers to convert Seatalk into NMEA.
Also, from what I hear, the issue of "daisy chaining" is somewhat
resolved by the new NMEA 2000 protocol. Easy connectors, simple
wiring. Still, NMEA reminds me of DOS based computing. (it amazes me
that windows has DOS underlying it!)
NMEA2000 is not a daisy chain, it is a similar setup like an ethernet
network where every device can send it's data on the network and listen to
any data on the network. A collision detection mechanism prevents data
corruption when two devices want to talk at the same time. It is based on
CAN.
Meindert
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