View Single Post
  #22   Report Post  
posted to rec.boats.cruising
Flying Pig[_2_] Flying Pig[_2_] is offline
external usenet poster
 
First recorded activity by BoatBanter: Mar 2009
Posts: 782
Default I spent all afternoon on a stupid NMEA 0183 adapter cable . . .

I read where the NMEA 0183 protocol supports up to five
listeners for each talker. That tells me one could split
the two wires on the GPS NMEA into five talker(+) and
five talker(-) and connect them to five different devices
or listeners as they are sometimes called.

One faulty listener shouldn't affect the four others that
aren't faulty.

--
Sir Gregory



The only talker I have (I'm pretty sure) is the GPS.

It comes through on a single pair, which is then tied to the plotter in/out,
VHF, SSB, autopilot, and computer.

Thus I infer that it should be able to handle it. Indeed, oddly, while it
does manage all 5, with the serial port disconnected (or the computer off),
it won't talk to the plotter.

I'm suspicious of one of the three legs of the RS232 going only to one of
the legs of the autopilot; perhaps without that reference, the autopilot
doesn't feed back into the NMEA or Seatalk system, killing the reference for
the plotter.

More work to do on that, yet...

Don't want to hijack the thread. More later in a new thread.

L8R

Skip

--

Morgan 461 #2
SV Flying Pig KI4MPC
See our galleries at www.justpickone.org/skip/gallery !
Follow us at http://groups.yahoo.com/group/TheFlyingPigLog
and/or http://groups.google.com/group/flyingpiglog

When a man comes to like a sea life, he is not fit to live on land.
- Dr. Samuel Johnson