Thread: NMEA mutiplexer
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Glen
 
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Default NMEA mutiplexer

On Wed, 22 Oct 2003 09:19:20 +0200, "Meindert Sprang"
tempted fate with:

"Glen Wiley Wilson" wrote in message
news

Again, I would never hook an RS-422 and
an RS-232 circuit together directly. Your mileage may vary.


In general: you can connect a RS-232 output to a NMEA RS-422 input by
connecting teh TX or OUT from the RS-232 to the + or 'A' from an NMEA in,
while connecting the - or B from NMEA in to the ground of teh RS-232 output.
The other way around (RS-422 out to RS-232 in) will mosty not work.

Meindert

Yes, I have seen or done both. I even understand why it works that
way. I was merely stating a policy. When I spec something for
navigating a boat it has to be bulletproof, not a marginal "generally
works" type of thing.

Also, I don't like connecting anything to a ground except another
ground. Seems to me to be asking for several different kinds of
trouble. I am not any kind of an engineer, whereas I believe you are,
but that is my policy. As I said, other peoples's mileage may vary,
but I suspect we are more or less in agreement, or your products would
not be what they are.

On a different subject, do you know what's going on with NMEA2000?
Did it wind up being CAN, and is anyone supporting it yet? It looks
like a sweet deal for the instrument makers. RS-232/CAN convertors
are 3 times the price of RS-422/RS-232 and it looks as if they could
potentially lock out anyone who doesn't pony up the fee to get an ID
assigned. But maybe I'm just paranoid...




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